검색
검색 팝업 닫기

Ex) Article Title, Author, Keywords

Current Issue

Split Viewer

Review Article

Ann Liver Transplant 2024; 4(1): 10-15

Published online May 31, 2024 https://doi.org/10.52604/alt.24.0006

Copyright © The Korean Liver Transplantation Society.

Surveillance and management of de novo malignancy after liver transplantation

Woo-Hyoung Kang

Division of Liver Transplantation and Hepatobiliary Surgery, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea

Correspondence to:Woo-Hyoung Kang
Division of Liver Transplantation and Hepatobiliary Surgery, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, Korea
E-mail: romikwh@gmail.com
https://orcid.org/0000-0002-3734-3352

Received: April 14, 2024; Revised: May 10, 2024; Accepted: May 11, 2024

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/bync/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Liver transplantation (LT) has significantly improved long-term survival rates, but recipients face increased risks of de novo malignancy (DNM) due to immunosuppression. DNM patterns differ worldwide, with post-transplant lymphoproliferative disorder common in Western countries, while South Korea sees more gastric and colorectal cancers. Risk factors include immunosuppressive drugs, underlying conditions, and lifestyle factors. Screening strategies should be tailored to regional DNM patterns, with regular surveillance crucial for early detection and management. Minimizing immunosuppressant usage and prompt local treatment upon DNM detection offer favorable outcomes for LT recipients.

Keywords: Liver transplantation, De novo malignancy, Screening strategy, Management

Due to advancements in liver transplantation (LT) techniques, postoperative management, and the development of immunosuppressive agents, long-term survival after LT has markedly improved. However, long-term transplant survivors undergoing long-time immunosuppression face concerns about the potential risk of de novo malignancy (DNM) due to the direct oncogenicity of immunosuppressive agents and susceptibility to viral infections. Kim et al. [1] reported a study on the long-term outcomes of patients who underwent LT at a single big center over two years from January 2000 to December 2001. The 20-year survival rates after LT were reported to be 62.6% for adult living donor transplants, 68.2% for adult deceased donor transplants, and 77.3% for pediatric transplants. In the study analyzing post-transplant deaths occurring three months later, the most common causes were pneumonia and graft failure, followed by DNM. According to a study by Åberg et al. [2] in 2015, comparing mortality rates of 3,299 North European liver transplant patients from 1985 to 2009 with the general population, patients surviving over one-year post-transplant had a 2.4 times higher risk of death compared to the general population. Notably, those under 75 years old showed a 5.8 times higher risk of mortality. The leading causes of death one-year post-transplant were malignancies, recurrence of liver disease, and cardiovascular diseases, in that order. In conclusion, the incidence of DNM is higher in long-term survivors, emphasizing the need for increased vigilance, especially in the meticulous screening for malignancies compared to the general population. Based on another study utilizing the Canadian Cancer Registry, it is evident that young transplant patients experience a higher incidence of malignancies compared to the general population. Moreover, the occurrence of malignancies significantly rises after the age of 45 in these patients. This study indicates that the incidence of DNM increases within the first year after LT, with a notable surge in mortality due to malignancies occurring between 1- and 7-years post-transplant. Therefore, regular surveillance is crucial from the first year of LT, particularly for young patients who may necessitate more proactive surveillance and treatment strategies [3].

Table 1 provides a comprehensive overview of research on the incidence of DNM after LT in both Western and Asian populations [3-12]. The incidence rate is typically expressed as the standardized incidence rate (SIR), indicating malignancy occurrence relative to the general population. In the United States, as per the United Network for Organ Sharing registry [4], post-transplant lymphoproliferative disorder (PTLD), skin cancer, and head and neck cancer are common DNMs, while prostate and breast cancer are less frequent. Similar trends are observed in the Canadian organ replacement registry database [3], and Italian studies indicate a comparable prevalence of cancer types, with notable proportions of gastric and colorectal cancers in their datasets [5]. According to an interesting study by Haider et al. [13], the investigation into the reasons for readmission of liver transplant patients in the United States from 2016 to 2018 revealed that 7.28% of readmissions were due to DNM. Racial disparities in DNM incidence are identified, with Hispanic patients showing a predisposition to PTLD, gastrointestinal, and urinary cancers, while black patients exhibit higher incidences of lung and reproductive organ cancers. White patients demonstrate higher incidences of PTLD, lung cancer, skin cancer, head and neck cancers, among others. This racial variability underscores diverse DNM patterns among different ethnic groups. Summarizing the overall pattern of DNMs in Western countries, PTLD is the most common, with a higher incidence of skin cancer, lung cancer, and head and neck cancer. The SIR for solid organ cancers is approximately double that of the general population, while for hematological malignancies, it is around 30 times higher. Interestingly, the SIR for prostate cancer and breast cancer is reported to be lower compared to other cancer types.

Table 1 De novo malignancy (DNM) incidence and standardized incidence rate (SIR) in Western country and East Asia

AuthorCountryYearTotal patients (n)DNM patients (n)Transplantation periodSIRDNM incidence (%)
Jiang et al. [3]Canada20082,0341131983–19982.55.6
Engels et al. [4]USA201137,8881,5631995–20042.14.1
Taborelli et al. [5]Italy20192,8322661985–20141.89.4
Sérée et al. [8]France201811,2261,2001993–20122.210.7
Park et al. [6]Korea20121,952441998–20087.7 (M), 7.3 (F)2.3
Shin et al. [9]Korea20131,180341995–20102.9
Kaneko et al. [10]Japan2013360271996–20121.87.2
Gao et al. [11]China2015466142005–20129.53.0
Park et al. [12]Korea20193,8222132007–20153.43 (M), 2.30 (F)5.6
Kim et al. [7]Korea20211,793701988–20183.9

M, male; F, female; –, not available.



In comparison to the Western world, the incidence of post-transplant cancer in Asia, particularly in South Korea, shows a different pattern. Researchers like Park et al. [6] and Kim et al. [7] conducted studies in major transplant centers in South Korea and found consistent results. Their studies identified a high prevalence of PTLD, stomach cancer, colorectal cancer, lung cancer, prostate cancer, and breast cancer among post-transplant patients. The incidence of stomach and colorectal cancers was notably higher among transplant recipients in Korea, which is consistent with the overall cancer landscape in the Korean general population. Interestingly, they also found an increased occurrence of cancers like prostate and breast, which are less common in Western countries.

There are several factors that can contribute to the development of DNM. These factors include the use of immunosuppressive drugs in transplant recipients, which can make them more susceptible to viral infections that have oncogenic properties, ultimately leading to DNM. For example, PTLD is associated with Epstein-Barr virus (EBV), while Kaposi sarcoma is related to human herpesvirus. Other underlying conditions like primary sclerosing cholangitis (PSC) and alcoholic liver cirrhosis can also contribute to DNM. PSC is correlated with colorectal and skin cancers, while alcoholic liver cirrhosis is related to head and neck cancer, lung cancer, colorectal cancer, and other cancers. Lifestyle habits such as smoking, alcohol consumption, sunlight exposure, and dietary factors are also recognized as factors influencing the occurrence of DNM. Smoking is associated with lung cancer, head and neck cancer, stomach cancer, and colorectal cancer, while alcohol consumption is related to colorectal cancer among others. Sunlight exposure is linked to skin cancer, while dietary factors are associated with stomach cancer, among others [14].

PTLD

PTLD is known to occur in 1% to 5.5% of LT patients, with a higher risk when the recipient is EBV seronegative and receives an organ from an EBV seropositive donor. PTLD can develop within a month after LT and may continue to occur for decades. The risk is increased in patients with strong immunosuppression or immunosuppressive agents like azathioprine, calcineurin inhibitors (CNIs), or anti-thymocyte agents. PTLD is recognized as a major complication in both Western and Eastern transplant patients [15].

Stomach Cancer

According to studies reported by various centers in South Korea, except for PTLD, gastric cancer is the most commonly occurring DNM. In a retrospective study conducted by Gong et al. [16] in 2016 involving 19 patients who developed gastric cancer after LT, they suggested that annual screening for post-transplant gastric cancer contributes to early detection and improves patient survival rates. Additionally, Kim et al. [17] emphasized the importance of annual endoscopy and computed tomography (CT) scans, reporting that laparoscopic gastrectomy can be safely performed in patients requiring surgical treatment for gastric cancer after LT. Another study suggested that in terms of surgical treatment, only active surgery following early diagnosis could be expected to have non-inferior mortality rates for transplant recipients compared to the general population [18].

Lung Cancer

In 2023, a meta-analysis was conducted to investigate the occurrence of lung cancer after LT. The study combined data from 15 different studies involving 76,897 liver transplant recipients. The results showed that the incidence of lung cancer was twice as high among these patients compared to the general population (SIR: 2.06). It is worth noting that low-dose chest CT screening was recommended for patients who had risk factors such as a history of smoking or alcoholic liver disease [19]. In another study comparing the survival rates, there was no significant difference in survival between liver transplant recipients and the general population. However, it was notable that liver transplant recipients had a higher rate of early screening. Additionally, when comparing liver transplant recipients with lung cancer to the overall transplant population, a significantly lower survival rate was observed, emphasizing once again the importance of appropriate screening for early diagnosis [20].

Colorectal Cancer

Risk factors for de novo colorectal cancer include primary PSC, non-alcoholic fatty liver disease (NASH) with hepatocellular carcinoma (HCC), obesity, and smoking. Studies on de novo colorectal cancer vary in conclusions across different countries. A multi-center study in the United Kingdom reported that LT alone does not increase the risk of colorectal cancer. However, patients with PSC or ulcerative colitis (UC) were found to have a significantly higher risk [21]. On the other hand, a meta-analysis in the United States suggested that even in the absence of autoimmune-related liver disease, the incidence of colorectal cancer in liver transplant recipients is nearly doubled compared to the general population [22]. In a South Korean study, out of 8,734 patients who underwent liver and kidney transplantation, 66 cases of colorectal cancer were identified. Among them, 33 patients, excluding those with endoscopic resection and 4-stage patients, underwent surgery, and their outcomes were reported. There were no PSC or UC patients in this group. The analysis showed that the incidence of colorectal cancer in liver transplant recipients was 3.10 times higher in men and 2.25 times higher in women compared to the general population. Survival analysis revealed that stage 1 patients did not have significantly lower overall survival than the general population, and even stage 2-3 patients did not show extremely poor survival rates. The study emphasizes the necessity of early diagnosis and suggests that early treatment does not worsen the survival rate compared to the general population [23].

Other DNMs

As mentioned earlier, DNMs such as prostate cancer or breast cancer have been reported to have lower incidence rates in the general population in Western countries. However, in Korea, prostate cancer is considered one of the cancers with a high incidence rate, and it is known to occur in transplant recipients occasionally. Therefore, regular screening is recommended according to the surveillance guidelines for the general population. On the other hand, skin cancer is prevalent in Western countries and is also frequently observed in the DNM of Western transplant recipients. Skin cancer is associated with risk factors such as excessive sun exposure or the use of azathioprine. A full-body skin examination by a dermatologist is crucial for diagnosis. Various non-melanomatous skin tumors, including melanoma, squamous cell carcinoma, and basal cell carcinoma, can occur. However, skin cancer incidence is reported to be very low in Korea.

The well-known guidelines for “post-liver transplantation de novo malignancies (DNM)” are the ILTS-SETH Consensus Conference Guideline published in the Transplantation in 2022. These guidelines provide detailed recommendations on post-transplant screening methods and intervals for various types of cancers. In summary, it is as follows: annual full-body skin exams for skin cancer and annual colonoscopies for individuals with inflammatory bowel disease or PSC. Liver transplant recipients with NASH/HCC after age 50 are advised colonoscopies every five years. Ex-smokers should undergo annual low-dose CT chest scans for lung cancer, and those with oropharyngeal/head and neck cancers should have annual ENT (ear, nose, and throat) exams. Females require annual pelvic exams, Papanicolaou tests, and human papillomavirus testing for cervical/vulvar/vaginal cancer screening. Mammography is recommended annually for breast cancer, and males should follow general population guidelines for prostate-specific antigen screening. Individuals with a history of renal cell cancer, polycystic kidney disease, or Von Hippel-Lindau disease should undergo annual CT abdomen scans for renal cancers.

However, liver transplant recipients in Korea exhibit a DNM occurrence pattern similar to that of the general population, presenting a different trend than Western countries. Excluding PTLD, gastric cancer is the most common, and colorectal cancer unrelated to PSC/UC is also frequently reported. Therefore, directly applying the screening methods recommended by the ILTS guidelines may not be appropriate in Korea, and modifications seem necessary. Furthermore, in Korea, there is a national cancer screening program targeting the entire population. This program recommends screening for five prevalent cancers in Korea—stomach, liver, colorectal, breast, and cervical cancers—and providing financial support for the screenings. Effectively utilizing this system for screening DNM would likely be efficient. Although lung cancer is not included in the free screening, a low-dose CT is recommended every two years for high-risk individuals. On the other hand, due to the common occurrence of stomach and colorectal cancers as DNM, it is recommended to personalize endoscopy screening intervals based on age and prior screening history. A previous study analyzed and recommended approaches in this regard [24]. Considering the situations, the author has outlined the recommended screening for DNM for LT patients in Table 2.

Table 2 Recommended protocol for de novo malignancy screening

Cancer typeRisk factorScreening methodScreening intervalRemarks
Gastric cancerAge under 40 yearsUpper endoscopyEvery 2 years
Age 40 years and aboveUpper endoscopyEvery 2 yearsNational Cancer Screening Program
Age 40 years and aboveUpper endoscopyEvery 1 yearPrevious endoscopy with intestinal metaplasia (+)
Lung cancerSmoking history (+)Low-dose chest CTEvery 2 yearsNational Cancer Screening Program
Colorectal cancerPSC/UCColonoscopyEvery 1 year
Age under 50 yearsColonoscopyEvery 5 years
Age 50 years and aboveColorectal screening (stool occult blood)Every 1 yearNational Cancer Screening Program, follow-up colonoscopy if abnormal
ColonoscopyEvery 3–5 years
ColonoscopyEvery 1–3 yearsPrevious colonoscopy with adenoma (+)
Breast cancerAge 40 years and above (females)MammographyEvery 2 yearsNational Cancer Screening Program
Prostate cancerAge 50 years and above (males with symptoms)PSA, DREEvery 1 year
Cervical cancerAge 20 years and above (females)Pap smearEvery 2 yearsNational Cancer Screening Program

CT, computed tomography; PSC, primary sclerosing cholangitis; UC, ulcerative colitis; PSA, prostate-specific antigen; DRE, digital rectal exam; Pap, Papanicolaou.


When a DNM is detected in liver transplant recipients, the treatment strategy can be divided into two main approaches. Firstly, immunosuppressant reduction is considered. Drugs like tacrolimus and cyclosporine, which belong to the CNI class, are known to decrease antiviral immunity, induce DNA damage, and upregulate cytokines promoting tumor growth. Therefore, upon DNM diagnosis, minimizing the use of CNIs is essential. Additionally, mTOR inhibitors or mycophenolate mofetil are recommended as they do not increase the risk of DNM and can reduce the need for CNIs. Secondly, aggressive local treatment, including surgery, is recommended upon early detection. As mentioned earlier, for gastric cancer, active interventions such as endoscopic submucosal dissection or surgical treatment are advisable. Similarly, for colorectal cancer, initiating prompt treatment can lead to a favorable prognosis.

This study investigated the occurrence patterns of prevalent DNMs in various countries using SIR analysis based on several papers. Additionally, it was observed that the types of cancers prevalent in the general population in Korea are similar to those commonly occurring as DNMs after LT. This suggests the need for transplant centers worldwide to develop screening and management strategies tailored to the types of cancers that occur more frequently based on regional and racial characteristics. Naturally, the screening strategies for DNM emphasized in this study are based on cancer incidence rates in Korea, which may limit their global applicability. Therefore, the author hopes that this paper serves as a catalyst for countries with a high prevalence of LT to conduct their research tailored to their respective situations and cancer incidence rates. However, regardless of differences in cancer incidence rates among countries, adherence to well-established guidelines for screening intervals and methods for prevalent cancers is essential. Referring to recognized guidelines such as the ILTS-SETH guidelines or the recently published APASL guidelines would be appropriate [14,25].

Liver transplant recipients face a twofold increased risk of solid organ malignancies and approximately a 30-fold increased risk of hematologic malignancies compared to the general population. Among various DNMs, PTLD is the most common. The types and patterns of DNM vary globally based on regional and lifestyle factors. In South Korea, gastric, colorectal, lung, prostate, and breast cancers are commonly diagnosed, emphasizing the importance of regular screening for post-liver transplant survivors. Upon discovering a DNM, minimizing CNI usage and actively pursuing local treatments offer a promising prognosis.

  1. Kim M, Hwang S, Ahn CS, Moon DB, Ha TY, Song GW, et al. Twenty-year longitudinal follow-up after liver transplantation: a single-center experience with 251 consecutive patients. Korean J Transplant 2022;36:45-53.
    Pubmed KoreaMed CrossRef
  2. Åberg F, Gissler M, Karlsen TH, Ericzon BG, Foss A, Rasmussen A, et al. Differences in long-term survival among liver transplant recipients and the general population: a population-based Nordic study. Hepatology 2015;61:668-677.
    Pubmed CrossRef
  3. Jiang Y, Villeneuve PJ, Fenton SS, Schaubel DE, Lilly L, Mao Y. Liver transplantation and subsequent risk of cancer: findings from a Canadian cohort study. Liver Transpl 2008;14:1588-1597.
    Pubmed CrossRef
  4. Engels EA, Pfeiffer RM, Fraumeni JF Jr, Kasiske BL, Israni AK, Snyder JJ, et al. Spectrum of cancer risk among US solid organ transplant recipients. JAMA 2011;306:1891-1901.
    Pubmed KoreaMed CrossRef
  5. Taborelli M, Piselli P, Ettorre GM, Baccarani U, Burra P, Lauro A, et al. Survival after the diagnosis of de novo malignancy in liver transplant recipients. Int J Cancer 2019;144:232-239.
    Pubmed CrossRef
  6. Park HW, Hwang S, Ahn CS, Kim KH, Moon DB, Ha TY, et al. De novo malignancies after liver transplantation: incidence comparison with the Korean cancer registry. Transplant Proc 2012;44:802-805.
    Pubmed CrossRef
  7. Kim S, Rovgaliyev B, Lee JM, Lee KW, Hong SK, Cho JH, et al. Clinical significance of de novo malignancy after liver transplant: a single-center study. Transplant Proc 2021;53:200-206.
    Pubmed CrossRef
  8. Sérée O, Altieri M, Guillaume E, De Mil R, Lobbedez T, Robinson P, et al. Longterm risk of solid organ de novo malignancies after liver transplantation: a French national study on 11,226 patients. Liver Transpl 2018;24:1425-1436.
    Pubmed CrossRef
  9. Shin M, Moon HH, Kim JM, Park JB, Kwon CH, Kim SJ, et al. Comparison of the incidence of de novo malignancy in liver or kidney transplant recipients: analysis of 2673 consecutive cases in a single center. Transplant Proc 2013;45:3019-3023.
    Pubmed CrossRef
  10. Kaneko J, Sugawara Y, Tamura S, Aoki T, Sakamoto Y, Hasegawa K, et al. De novo malignancies after adult-to-adult living-donor liver transplantation with a malignancy surveillance program: comparison with a Japanese population-based study. Transplantation 2013;95:1142-1147.
    Pubmed CrossRef
  11. Gao PJ, Gao J, Li Z, Hu ZP, Zhu JY. De novo malignancy after liver transplantation: a single-center experience of 14 cases. Ann Surg Treat Res 2015;88:222-228.
    Pubmed KoreaMed CrossRef
  12. Park B, Yoon J, Choi D, Kim HJ, Jung YK, Kwon OJ, et al. De novo cancer incidence after kidney and liver transplantation: results from a nationwide population based data. Sci Rep 2019;9:17202.
    Pubmed KoreaMed CrossRef
  13. Haider M, Bapatla A, Ismail R, Chaudhary AJ, Iqbal S, Haider SM. The spectrum of malignant neoplasms among liver transplant recipients: sociodemographic factors, mortality, and hospital burden. Int J Med Sci 2022;19:299-309.
    Pubmed KoreaMed CrossRef
  14. Colmenero J, Tabrizian P, Bhangui P, Pinato DJ, Rodríguez-Perálvarez ML, Sapisochin G, et al. De novo malignancy after liver transplantation: risk assessment, prevention, and management-guidelines from the ILTS-SETH Consensus Conference. Transplantation 2022;106:e30-e45.
    Pubmed CrossRef
  15. Dierickx D, Habermann TM. Post-transplantation lymphoproliferative disorders in adults. N Engl J Med 2018;378:549-562.
    Pubmed CrossRef
  16. Gong CS, Yoo MW, Kim BS, Hwang S, Kim KH, Yook JH, et al. De novo gastric cancer after liver transplantation. Ann Transplant 2016;21:386-391.
    Pubmed CrossRef
  17. Kim S, Lee HJ, Alzahrani F, Kim J, Kim SH, Kim S, et al. Clinical outcomes of gastric cancer surgery after liver transplantation. Ann Surg Treat Res 2023;104:101-108.
    Pubmed KoreaMed CrossRef
  18. Ko CS, Jheong JH, Jeong SA, Kim BS, Yook JH, Kim BS, et al. Safety evaluation of curative gastrectomy for gastric cancer patients who underwent liver transplantation: a comparative study with conventional gastrectomy for gastric cancer patients. World J Surg Oncol 2023;21:145.
    Pubmed KoreaMed CrossRef
  19. Fu C, Li X, Chen Y, Long X, Liu K. Lung cancer incidences after liver transplantation: a systematic review and meta-analysis. Cancer Med 2023;12:16119-16128.
    Pubmed KoreaMed CrossRef
  20. Kocher F, Finkenstedt A, Fiegl M, Graziadei I, Gamerith G, Oberaigner W, et al. Liver transplantation-associated lung cancer: comparison of clinical parameters and outcomes. Clin Lung Cancer 2015;16:e75-e81.
    Pubmed CrossRef
  21. Rompianesi G, Ravikumar R, Jose S, Allison M, Athale A, Creamer F, et al. Incidence and outcome of colorectal cancer in liver transplant recipients: a national, multicentre analysis on 8115 patients. Liver Int 2019;39:353-360.
    Pubmed CrossRef
  22. Komaki Y, Komaki F, Micic D, Ido A, Sakuraba A. Risk of colorectal cancer in chronic liver diseases: a systematic review and meta-analysis. Gastrointest Endosc 2017;86:93-104.e5.
    Pubmed CrossRef
  23. Kim M, Kim CW, Hwang S, Kim YH, Lee JL, Yoon YS, et al. Characteristics and prognosis of colorectal cancer after liver or kidney transplantation. World J Surg 2021;45:3206-3213.
    Pubmed CrossRef
  24. Jung DH, Hwang S, Song GW, Ahn CS, Moon DB, Ha TY, et al. Survival benefit of early cancer detection through regular endoscopic screening for de novo gastric and colorectal cancers in Korean liver transplant recipients. Transplant Proc 2016;48:145-151.
    Pubmed CrossRef
  25. Kim DS, Yoon YI, Kim BK, Choudhury A, Kulkarni A, Park JY, et al. Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation. Hepatol Int 2024;18:299-383.
    Pubmed CrossRef

Article

Review Article

Ann Liver Transplant 2024; 4(1): 10-15

Published online May 31, 2024 https://doi.org/10.52604/alt.24.0006

Copyright © The Korean Liver Transplantation Society.

Surveillance and management of de novo malignancy after liver transplantation

Woo-Hyoung Kang

Division of Liver Transplantation and Hepatobiliary Surgery, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea

Correspondence to:Woo-Hyoung Kang
Division of Liver Transplantation and Hepatobiliary Surgery, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, Korea
E-mail: romikwh@gmail.com
https://orcid.org/0000-0002-3734-3352

Received: April 14, 2024; Revised: May 10, 2024; Accepted: May 11, 2024

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/bync/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Liver transplantation (LT) has significantly improved long-term survival rates, but recipients face increased risks of de novo malignancy (DNM) due to immunosuppression. DNM patterns differ worldwide, with post-transplant lymphoproliferative disorder common in Western countries, while South Korea sees more gastric and colorectal cancers. Risk factors include immunosuppressive drugs, underlying conditions, and lifestyle factors. Screening strategies should be tailored to regional DNM patterns, with regular surveillance crucial for early detection and management. Minimizing immunosuppressant usage and prompt local treatment upon DNM detection offer favorable outcomes for LT recipients.

Keywords: Liver transplantation, De novo malignancy, Screening strategy, Management

INTRODUCTION

Due to advancements in liver transplantation (LT) techniques, postoperative management, and the development of immunosuppressive agents, long-term survival after LT has markedly improved. However, long-term transplant survivors undergoing long-time immunosuppression face concerns about the potential risk of de novo malignancy (DNM) due to the direct oncogenicity of immunosuppressive agents and susceptibility to viral infections. Kim et al. [1] reported a study on the long-term outcomes of patients who underwent LT at a single big center over two years from January 2000 to December 2001. The 20-year survival rates after LT were reported to be 62.6% for adult living donor transplants, 68.2% for adult deceased donor transplants, and 77.3% for pediatric transplants. In the study analyzing post-transplant deaths occurring three months later, the most common causes were pneumonia and graft failure, followed by DNM. According to a study by Åberg et al. [2] in 2015, comparing mortality rates of 3,299 North European liver transplant patients from 1985 to 2009 with the general population, patients surviving over one-year post-transplant had a 2.4 times higher risk of death compared to the general population. Notably, those under 75 years old showed a 5.8 times higher risk of mortality. The leading causes of death one-year post-transplant were malignancies, recurrence of liver disease, and cardiovascular diseases, in that order. In conclusion, the incidence of DNM is higher in long-term survivors, emphasizing the need for increased vigilance, especially in the meticulous screening for malignancies compared to the general population. Based on another study utilizing the Canadian Cancer Registry, it is evident that young transplant patients experience a higher incidence of malignancies compared to the general population. Moreover, the occurrence of malignancies significantly rises after the age of 45 in these patients. This study indicates that the incidence of DNM increases within the first year after LT, with a notable surge in mortality due to malignancies occurring between 1- and 7-years post-transplant. Therefore, regular surveillance is crucial from the first year of LT, particularly for young patients who may necessitate more proactive surveillance and treatment strategies [3].

INCIDENCE OF DNM

Table 1 provides a comprehensive overview of research on the incidence of DNM after LT in both Western and Asian populations [3-12]. The incidence rate is typically expressed as the standardized incidence rate (SIR), indicating malignancy occurrence relative to the general population. In the United States, as per the United Network for Organ Sharing registry [4], post-transplant lymphoproliferative disorder (PTLD), skin cancer, and head and neck cancer are common DNMs, while prostate and breast cancer are less frequent. Similar trends are observed in the Canadian organ replacement registry database [3], and Italian studies indicate a comparable prevalence of cancer types, with notable proportions of gastric and colorectal cancers in their datasets [5]. According to an interesting study by Haider et al. [13], the investigation into the reasons for readmission of liver transplant patients in the United States from 2016 to 2018 revealed that 7.28% of readmissions were due to DNM. Racial disparities in DNM incidence are identified, with Hispanic patients showing a predisposition to PTLD, gastrointestinal, and urinary cancers, while black patients exhibit higher incidences of lung and reproductive organ cancers. White patients demonstrate higher incidences of PTLD, lung cancer, skin cancer, head and neck cancers, among others. This racial variability underscores diverse DNM patterns among different ethnic groups. Summarizing the overall pattern of DNMs in Western countries, PTLD is the most common, with a higher incidence of skin cancer, lung cancer, and head and neck cancer. The SIR for solid organ cancers is approximately double that of the general population, while for hematological malignancies, it is around 30 times higher. Interestingly, the SIR for prostate cancer and breast cancer is reported to be lower compared to other cancer types.

Table 1 . De novo malignancy (DNM) incidence and standardized incidence rate (SIR) in Western country and East Asia.

AuthorCountryYearTotal patients (n)DNM patients (n)Transplantation periodSIRDNM incidence (%)
Jiang et al. [3]Canada20082,0341131983–19982.55.6
Engels et al. [4]USA201137,8881,5631995–20042.14.1
Taborelli et al. [5]Italy20192,8322661985–20141.89.4
Sérée et al. [8]France201811,2261,2001993–20122.210.7
Park et al. [6]Korea20121,952441998–20087.7 (M), 7.3 (F)2.3
Shin et al. [9]Korea20131,180341995–20102.9
Kaneko et al. [10]Japan2013360271996–20121.87.2
Gao et al. [11]China2015466142005–20129.53.0
Park et al. [12]Korea20193,8222132007–20153.43 (M), 2.30 (F)5.6
Kim et al. [7]Korea20211,793701988–20183.9

M, male; F, female; –, not available..



In comparison to the Western world, the incidence of post-transplant cancer in Asia, particularly in South Korea, shows a different pattern. Researchers like Park et al. [6] and Kim et al. [7] conducted studies in major transplant centers in South Korea and found consistent results. Their studies identified a high prevalence of PTLD, stomach cancer, colorectal cancer, lung cancer, prostate cancer, and breast cancer among post-transplant patients. The incidence of stomach and colorectal cancers was notably higher among transplant recipients in Korea, which is consistent with the overall cancer landscape in the Korean general population. Interestingly, they also found an increased occurrence of cancers like prostate and breast, which are less common in Western countries.

RISK FACTORS OF DNM

There are several factors that can contribute to the development of DNM. These factors include the use of immunosuppressive drugs in transplant recipients, which can make them more susceptible to viral infections that have oncogenic properties, ultimately leading to DNM. For example, PTLD is associated with Epstein-Barr virus (EBV), while Kaposi sarcoma is related to human herpesvirus. Other underlying conditions like primary sclerosing cholangitis (PSC) and alcoholic liver cirrhosis can also contribute to DNM. PSC is correlated with colorectal and skin cancers, while alcoholic liver cirrhosis is related to head and neck cancer, lung cancer, colorectal cancer, and other cancers. Lifestyle habits such as smoking, alcohol consumption, sunlight exposure, and dietary factors are also recognized as factors influencing the occurrence of DNM. Smoking is associated with lung cancer, head and neck cancer, stomach cancer, and colorectal cancer, while alcohol consumption is related to colorectal cancer among others. Sunlight exposure is linked to skin cancer, while dietary factors are associated with stomach cancer, among others [14].

CHARACTERISTICS OF DNMS IN EACH ORGAN

PTLD

PTLD is known to occur in 1% to 5.5% of LT patients, with a higher risk when the recipient is EBV seronegative and receives an organ from an EBV seropositive donor. PTLD can develop within a month after LT and may continue to occur for decades. The risk is increased in patients with strong immunosuppression or immunosuppressive agents like azathioprine, calcineurin inhibitors (CNIs), or anti-thymocyte agents. PTLD is recognized as a major complication in both Western and Eastern transplant patients [15].

Stomach Cancer

According to studies reported by various centers in South Korea, except for PTLD, gastric cancer is the most commonly occurring DNM. In a retrospective study conducted by Gong et al. [16] in 2016 involving 19 patients who developed gastric cancer after LT, they suggested that annual screening for post-transplant gastric cancer contributes to early detection and improves patient survival rates. Additionally, Kim et al. [17] emphasized the importance of annual endoscopy and computed tomography (CT) scans, reporting that laparoscopic gastrectomy can be safely performed in patients requiring surgical treatment for gastric cancer after LT. Another study suggested that in terms of surgical treatment, only active surgery following early diagnosis could be expected to have non-inferior mortality rates for transplant recipients compared to the general population [18].

Lung Cancer

In 2023, a meta-analysis was conducted to investigate the occurrence of lung cancer after LT. The study combined data from 15 different studies involving 76,897 liver transplant recipients. The results showed that the incidence of lung cancer was twice as high among these patients compared to the general population (SIR: 2.06). It is worth noting that low-dose chest CT screening was recommended for patients who had risk factors such as a history of smoking or alcoholic liver disease [19]. In another study comparing the survival rates, there was no significant difference in survival between liver transplant recipients and the general population. However, it was notable that liver transplant recipients had a higher rate of early screening. Additionally, when comparing liver transplant recipients with lung cancer to the overall transplant population, a significantly lower survival rate was observed, emphasizing once again the importance of appropriate screening for early diagnosis [20].

Colorectal Cancer

Risk factors for de novo colorectal cancer include primary PSC, non-alcoholic fatty liver disease (NASH) with hepatocellular carcinoma (HCC), obesity, and smoking. Studies on de novo colorectal cancer vary in conclusions across different countries. A multi-center study in the United Kingdom reported that LT alone does not increase the risk of colorectal cancer. However, patients with PSC or ulcerative colitis (UC) were found to have a significantly higher risk [21]. On the other hand, a meta-analysis in the United States suggested that even in the absence of autoimmune-related liver disease, the incidence of colorectal cancer in liver transplant recipients is nearly doubled compared to the general population [22]. In a South Korean study, out of 8,734 patients who underwent liver and kidney transplantation, 66 cases of colorectal cancer were identified. Among them, 33 patients, excluding those with endoscopic resection and 4-stage patients, underwent surgery, and their outcomes were reported. There were no PSC or UC patients in this group. The analysis showed that the incidence of colorectal cancer in liver transplant recipients was 3.10 times higher in men and 2.25 times higher in women compared to the general population. Survival analysis revealed that stage 1 patients did not have significantly lower overall survival than the general population, and even stage 2-3 patients did not show extremely poor survival rates. The study emphasizes the necessity of early diagnosis and suggests that early treatment does not worsen the survival rate compared to the general population [23].

Other DNMs

As mentioned earlier, DNMs such as prostate cancer or breast cancer have been reported to have lower incidence rates in the general population in Western countries. However, in Korea, prostate cancer is considered one of the cancers with a high incidence rate, and it is known to occur in transplant recipients occasionally. Therefore, regular screening is recommended according to the surveillance guidelines for the general population. On the other hand, skin cancer is prevalent in Western countries and is also frequently observed in the DNM of Western transplant recipients. Skin cancer is associated with risk factors such as excessive sun exposure or the use of azathioprine. A full-body skin examination by a dermatologist is crucial for diagnosis. Various non-melanomatous skin tumors, including melanoma, squamous cell carcinoma, and basal cell carcinoma, can occur. However, skin cancer incidence is reported to be very low in Korea.

SCREENING STRATEGY FOR DNM

The well-known guidelines for “post-liver transplantation de novo malignancies (DNM)” are the ILTS-SETH Consensus Conference Guideline published in the Transplantation in 2022. These guidelines provide detailed recommendations on post-transplant screening methods and intervals for various types of cancers. In summary, it is as follows: annual full-body skin exams for skin cancer and annual colonoscopies for individuals with inflammatory bowel disease or PSC. Liver transplant recipients with NASH/HCC after age 50 are advised colonoscopies every five years. Ex-smokers should undergo annual low-dose CT chest scans for lung cancer, and those with oropharyngeal/head and neck cancers should have annual ENT (ear, nose, and throat) exams. Females require annual pelvic exams, Papanicolaou tests, and human papillomavirus testing for cervical/vulvar/vaginal cancer screening. Mammography is recommended annually for breast cancer, and males should follow general population guidelines for prostate-specific antigen screening. Individuals with a history of renal cell cancer, polycystic kidney disease, or Von Hippel-Lindau disease should undergo annual CT abdomen scans for renal cancers.

However, liver transplant recipients in Korea exhibit a DNM occurrence pattern similar to that of the general population, presenting a different trend than Western countries. Excluding PTLD, gastric cancer is the most common, and colorectal cancer unrelated to PSC/UC is also frequently reported. Therefore, directly applying the screening methods recommended by the ILTS guidelines may not be appropriate in Korea, and modifications seem necessary. Furthermore, in Korea, there is a national cancer screening program targeting the entire population. This program recommends screening for five prevalent cancers in Korea—stomach, liver, colorectal, breast, and cervical cancers—and providing financial support for the screenings. Effectively utilizing this system for screening DNM would likely be efficient. Although lung cancer is not included in the free screening, a low-dose CT is recommended every two years for high-risk individuals. On the other hand, due to the common occurrence of stomach and colorectal cancers as DNM, it is recommended to personalize endoscopy screening intervals based on age and prior screening history. A previous study analyzed and recommended approaches in this regard [24]. Considering the situations, the author has outlined the recommended screening for DNM for LT patients in Table 2.

Table 2 . Recommended protocol for de novo malignancy screening.

Cancer typeRisk factorScreening methodScreening intervalRemarks
Gastric cancerAge under 40 yearsUpper endoscopyEvery 2 years
Age 40 years and aboveUpper endoscopyEvery 2 yearsNational Cancer Screening Program
Age 40 years and aboveUpper endoscopyEvery 1 yearPrevious endoscopy with intestinal metaplasia (+)
Lung cancerSmoking history (+)Low-dose chest CTEvery 2 yearsNational Cancer Screening Program
Colorectal cancerPSC/UCColonoscopyEvery 1 year
Age under 50 yearsColonoscopyEvery 5 years
Age 50 years and aboveColorectal screening (stool occult blood)Every 1 yearNational Cancer Screening Program, follow-up colonoscopy if abnormal
ColonoscopyEvery 3–5 years
ColonoscopyEvery 1–3 yearsPrevious colonoscopy with adenoma (+)
Breast cancerAge 40 years and above (females)MammographyEvery 2 yearsNational Cancer Screening Program
Prostate cancerAge 50 years and above (males with symptoms)PSA, DREEvery 1 year
Cervical cancerAge 20 years and above (females)Pap smearEvery 2 yearsNational Cancer Screening Program

CT, computed tomography; PSC, primary sclerosing cholangitis; UC, ulcerative colitis; PSA, prostate-specific antigen; DRE, digital rectal exam; Pap, Papanicolaou..


MANAGEMENT OF DNM AFTER LT

When a DNM is detected in liver transplant recipients, the treatment strategy can be divided into two main approaches. Firstly, immunosuppressant reduction is considered. Drugs like tacrolimus and cyclosporine, which belong to the CNI class, are known to decrease antiviral immunity, induce DNA damage, and upregulate cytokines promoting tumor growth. Therefore, upon DNM diagnosis, minimizing the use of CNIs is essential. Additionally, mTOR inhibitors or mycophenolate mofetil are recommended as they do not increase the risk of DNM and can reduce the need for CNIs. Secondly, aggressive local treatment, including surgery, is recommended upon early detection. As mentioned earlier, for gastric cancer, active interventions such as endoscopic submucosal dissection or surgical treatment are advisable. Similarly, for colorectal cancer, initiating prompt treatment can lead to a favorable prognosis.

DISCUSSION

This study investigated the occurrence patterns of prevalent DNMs in various countries using SIR analysis based on several papers. Additionally, it was observed that the types of cancers prevalent in the general population in Korea are similar to those commonly occurring as DNMs after LT. This suggests the need for transplant centers worldwide to develop screening and management strategies tailored to the types of cancers that occur more frequently based on regional and racial characteristics. Naturally, the screening strategies for DNM emphasized in this study are based on cancer incidence rates in Korea, which may limit their global applicability. Therefore, the author hopes that this paper serves as a catalyst for countries with a high prevalence of LT to conduct their research tailored to their respective situations and cancer incidence rates. However, regardless of differences in cancer incidence rates among countries, adherence to well-established guidelines for screening intervals and methods for prevalent cancers is essential. Referring to recognized guidelines such as the ILTS-SETH guidelines or the recently published APASL guidelines would be appropriate [14,25].

CONCLUSIONS

Liver transplant recipients face a twofold increased risk of solid organ malignancies and approximately a 30-fold increased risk of hematologic malignancies compared to the general population. Among various DNMs, PTLD is the most common. The types and patterns of DNM vary globally based on regional and lifestyle factors. In South Korea, gastric, colorectal, lung, prostate, and breast cancers are commonly diagnosed, emphasizing the importance of regular screening for post-liver transplant survivors. Upon discovering a DNM, minimizing CNI usage and actively pursuing local treatments offer a promising prognosis.

FUNDING

There was no funding related to this study.

CONFLICT OF INTEREST

All authors have no conflicts of interest to declare.

Table 1 De novo malignancy (DNM) incidence and standardized incidence rate (SIR) in Western country and East Asia

AuthorCountryYearTotal patients (n)DNM patients (n)Transplantation periodSIRDNM incidence (%)
Jiang et al. [3]Canada20082,0341131983–19982.55.6
Engels et al. [4]USA201137,8881,5631995–20042.14.1
Taborelli et al. [5]Italy20192,8322661985–20141.89.4
Sérée et al. [8]France201811,2261,2001993–20122.210.7
Park et al. [6]Korea20121,952441998–20087.7 (M), 7.3 (F)2.3
Shin et al. [9]Korea20131,180341995–20102.9
Kaneko et al. [10]Japan2013360271996–20121.87.2
Gao et al. [11]China2015466142005–20129.53.0
Park et al. [12]Korea20193,8222132007–20153.43 (M), 2.30 (F)5.6
Kim et al. [7]Korea20211,793701988–20183.9

M, male; F, female; –, not available.


Table 2 Recommended protocol for de novo malignancy screening

Cancer typeRisk factorScreening methodScreening intervalRemarks
Gastric cancerAge under 40 yearsUpper endoscopyEvery 2 years
Age 40 years and aboveUpper endoscopyEvery 2 yearsNational Cancer Screening Program
Age 40 years and aboveUpper endoscopyEvery 1 yearPrevious endoscopy with intestinal metaplasia (+)
Lung cancerSmoking history (+)Low-dose chest CTEvery 2 yearsNational Cancer Screening Program
Colorectal cancerPSC/UCColonoscopyEvery 1 year
Age under 50 yearsColonoscopyEvery 5 years
Age 50 years and aboveColorectal screening (stool occult blood)Every 1 yearNational Cancer Screening Program, follow-up colonoscopy if abnormal
ColonoscopyEvery 3–5 years
ColonoscopyEvery 1–3 yearsPrevious colonoscopy with adenoma (+)
Breast cancerAge 40 years and above (females)MammographyEvery 2 yearsNational Cancer Screening Program
Prostate cancerAge 50 years and above (males with symptoms)PSA, DREEvery 1 year
Cervical cancerAge 20 years and above (females)Pap smearEvery 2 yearsNational Cancer Screening Program

CT, computed tomography; PSC, primary sclerosing cholangitis; UC, ulcerative colitis; PSA, prostate-specific antigen; DRE, digital rectal exam; Pap, Papanicolaou.


References

  1. Kim M, Hwang S, Ahn CS, Moon DB, Ha TY, Song GW, et al. Twenty-year longitudinal follow-up after liver transplantation: a single-center experience with 251 consecutive patients. Korean J Transplant 2022;36:45-53.
    Pubmed KoreaMed CrossRef
  2. Åberg F, Gissler M, Karlsen TH, Ericzon BG, Foss A, Rasmussen A, et al. Differences in long-term survival among liver transplant recipients and the general population: a population-based Nordic study. Hepatology 2015;61:668-677.
    Pubmed CrossRef
  3. Jiang Y, Villeneuve PJ, Fenton SS, Schaubel DE, Lilly L, Mao Y. Liver transplantation and subsequent risk of cancer: findings from a Canadian cohort study. Liver Transpl 2008;14:1588-1597.
    Pubmed CrossRef
  4. Engels EA, Pfeiffer RM, Fraumeni JF Jr, Kasiske BL, Israni AK, Snyder JJ, et al. Spectrum of cancer risk among US solid organ transplant recipients. JAMA 2011;306:1891-1901.
    Pubmed KoreaMed CrossRef
  5. Taborelli M, Piselli P, Ettorre GM, Baccarani U, Burra P, Lauro A, et al. Survival after the diagnosis of de novo malignancy in liver transplant recipients. Int J Cancer 2019;144:232-239.
    Pubmed CrossRef
  6. Park HW, Hwang S, Ahn CS, Kim KH, Moon DB, Ha TY, et al. De novo malignancies after liver transplantation: incidence comparison with the Korean cancer registry. Transplant Proc 2012;44:802-805.
    Pubmed CrossRef
  7. Kim S, Rovgaliyev B, Lee JM, Lee KW, Hong SK, Cho JH, et al. Clinical significance of de novo malignancy after liver transplant: a single-center study. Transplant Proc 2021;53:200-206.
    Pubmed CrossRef
  8. Sérée O, Altieri M, Guillaume E, De Mil R, Lobbedez T, Robinson P, et al. Longterm risk of solid organ de novo malignancies after liver transplantation: a French national study on 11,226 patients. Liver Transpl 2018;24:1425-1436.
    Pubmed CrossRef
  9. Shin M, Moon HH, Kim JM, Park JB, Kwon CH, Kim SJ, et al. Comparison of the incidence of de novo malignancy in liver or kidney transplant recipients: analysis of 2673 consecutive cases in a single center. Transplant Proc 2013;45:3019-3023.
    Pubmed CrossRef
  10. Kaneko J, Sugawara Y, Tamura S, Aoki T, Sakamoto Y, Hasegawa K, et al. De novo malignancies after adult-to-adult living-donor liver transplantation with a malignancy surveillance program: comparison with a Japanese population-based study. Transplantation 2013;95:1142-1147.
    Pubmed CrossRef
  11. Gao PJ, Gao J, Li Z, Hu ZP, Zhu JY. De novo malignancy after liver transplantation: a single-center experience of 14 cases. Ann Surg Treat Res 2015;88:222-228.
    Pubmed KoreaMed CrossRef
  12. Park B, Yoon J, Choi D, Kim HJ, Jung YK, Kwon OJ, et al. De novo cancer incidence after kidney and liver transplantation: results from a nationwide population based data. Sci Rep 2019;9:17202.
    Pubmed KoreaMed CrossRef
  13. Haider M, Bapatla A, Ismail R, Chaudhary AJ, Iqbal S, Haider SM. The spectrum of malignant neoplasms among liver transplant recipients: sociodemographic factors, mortality, and hospital burden. Int J Med Sci 2022;19:299-309.
    Pubmed KoreaMed CrossRef
  14. Colmenero J, Tabrizian P, Bhangui P, Pinato DJ, Rodríguez-Perálvarez ML, Sapisochin G, et al. De novo malignancy after liver transplantation: risk assessment, prevention, and management-guidelines from the ILTS-SETH Consensus Conference. Transplantation 2022;106:e30-e45.
    Pubmed CrossRef
  15. Dierickx D, Habermann TM. Post-transplantation lymphoproliferative disorders in adults. N Engl J Med 2018;378:549-562.
    Pubmed CrossRef
  16. Gong CS, Yoo MW, Kim BS, Hwang S, Kim KH, Yook JH, et al. De novo gastric cancer after liver transplantation. Ann Transplant 2016;21:386-391.
    Pubmed CrossRef
  17. Kim S, Lee HJ, Alzahrani F, Kim J, Kim SH, Kim S, et al. Clinical outcomes of gastric cancer surgery after liver transplantation. Ann Surg Treat Res 2023;104:101-108.
    Pubmed KoreaMed CrossRef
  18. Ko CS, Jheong JH, Jeong SA, Kim BS, Yook JH, Kim BS, et al. Safety evaluation of curative gastrectomy for gastric cancer patients who underwent liver transplantation: a comparative study with conventional gastrectomy for gastric cancer patients. World J Surg Oncol 2023;21:145.
    Pubmed KoreaMed CrossRef
  19. Fu C, Li X, Chen Y, Long X, Liu K. Lung cancer incidences after liver transplantation: a systematic review and meta-analysis. Cancer Med 2023;12:16119-16128.
    Pubmed KoreaMed CrossRef
  20. Kocher F, Finkenstedt A, Fiegl M, Graziadei I, Gamerith G, Oberaigner W, et al. Liver transplantation-associated lung cancer: comparison of clinical parameters and outcomes. Clin Lung Cancer 2015;16:e75-e81.
    Pubmed CrossRef
  21. Rompianesi G, Ravikumar R, Jose S, Allison M, Athale A, Creamer F, et al. Incidence and outcome of colorectal cancer in liver transplant recipients: a national, multicentre analysis on 8115 patients. Liver Int 2019;39:353-360.
    Pubmed CrossRef
  22. Komaki Y, Komaki F, Micic D, Ido A, Sakuraba A. Risk of colorectal cancer in chronic liver diseases: a systematic review and meta-analysis. Gastrointest Endosc 2017;86:93-104.e5.
    Pubmed CrossRef
  23. Kim M, Kim CW, Hwang S, Kim YH, Lee JL, Yoon YS, et al. Characteristics and prognosis of colorectal cancer after liver or kidney transplantation. World J Surg 2021;45:3206-3213.
    Pubmed CrossRef
  24. Jung DH, Hwang S, Song GW, Ahn CS, Moon DB, Ha TY, et al. Survival benefit of early cancer detection through regular endoscopic screening for de novo gastric and colorectal cancers in Korean liver transplant recipients. Transplant Proc 2016;48:145-151.
    Pubmed CrossRef
  25. Kim DS, Yoon YI, Kim BK, Choudhury A, Kulkarni A, Park JY, et al. Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation. Hepatol Int 2024;18:299-383.
    Pubmed CrossRef
The Korean Liver Transplantation Society

Vol.4 No.1
May 2024

pISSN 2765-5121
eISSN 2765-6098

Stats or Metrics

Share this article on :

  • line