Incidence and management of colorectal cancer in liver transplant recipients

Long-Term Care of the Liver Transplant Recipient

Reflecting continued enhancements of surgical techniques and immunosuppression, liver transplant recipients are experiencing increased longevity. Once patients have successfully navigated the perioperative and early posttransplant period, their survival depends on management of immunosuppression to minimize systemic side effects that will contribute to the development of medical comorbidities while avoiding rejection. This includes mitigating cardiovascular risk factors and other components of the metabolic syndrome. The concept of transplant survivorship emphasizes a holistic approach to improving a patient's quality of life. Highlighting not only the medical management, transplant survivorship also stresses the psychological, mental, and spiritual well-being to further improve long-term outcomes.

Frontiers and Controversies in De Novo Gastrointestinal Tumors After Organ Transplantation: Current Progress and Future Directions

The increasing success of organ transplantation has significantly improved survival for patients with end-stage diseases, yet it introduces a complex dilemma: the elevated risk for the development of de novo gastrointestinal (GI) tumors. The sustained immunosuppression required to maintain graft function paradoxically undermines the body's natural defenses against cancer, leading to a higher incidence, aggressive progression, and atypical presentations of GI tumors among transplant recipients compared with the general population. This presents a pressing challenge: balancing the dual imperatives of preventing graft rejection and effectively managing malignancies. Current treatment paradigms, including surgical approaches, chemotherapy, radiation therapy, and the emerging role of immunotherapy, are fraught with complexities due to the altered immune landscape in these patients. This review underscores the critical need to understand the multifaceted relationship between post-transplantation immunosuppression and tumorigenesis, providing a comprehensive exploration of epidemiologic shifts, pathophysiologic insights, and the intricacies of the tumor microenvironment in this unique patient population. Understanding and managing GI tumors in transplant recipients is not only a clinical challenge, but also a necessary frontier in transplant oncology, promising to refine therapeutic strategies and improve the longevity and quality of life for this growing patient cohort.

Gut mucosa alterations after kidney transplantation: a cross sectional study

BACKGROUND

Kidney transplant recipients (KTRs) rely on immunosuppressants like mycophenolate to prevent organ rejection. However, mycophenolate often causes intestinal symptoms and inflammation in various organs, including the skin and the colon. While KTRs have an increased risk for skin cancer, the risk of colorectal cancer is not increased. Elucidating the histological alterations in the colon of KTRs and comparing these changes with known skin alterations would help understand how immunosuppressants influence cancer development and progression.

METHODS

Whole slide images from gut biopsies (Non-transplanted subjects n = 35, KTRs n = 49) were analyzed using the ImageJ and R programming environment. A total of 22,035 epithelial cells, 38,870 interstitial cells, 3465 epithelial cell mitoses, and 7477 endothelial cells, each characterized by multiple microscopy parameters, from a total of 1788 glands were analyzed. The large database was subsequently analyzed to verify the changes of inflammatory milieu in KTRs and in cancer.

RESULTS

KTRs without colon-cancer showed a significantly higher density of interstitial cells in the colon compared to non-transplanted patients. Moreover, the increase in interstitial cell number was accompanied by subtle modifications in the architecture of the colon glands, without altering the epithelial cell density. We could not identify significant structural modifications in cancer samples between KTRs and non-transplanted patients.

CONCLUSIONS

Our findings demonstrate an increased number of resident interstitial cells in the colon of KTRs, as in other patients treated with mycophenolate. These changes are associated with subtle alterations in the architecture of colon glands.

Characteristics of de novo cancer in liver transplant recipients

Liver transplant recipients receive immunosuppressive treatment to avoid organ rejection, increasing the risk of developing de novo cancer after transplantation. We investigated the cumulative incidence of de novo cancer in a cohort of Danish liver transplant recipients. The study was a retrospective cohort study of adult liver transplant recipients transplanted at Rigshospitalet, Copenhagen, Denmark, between January 1, 2010, and December 31, 2019. De novo cancer was defined as cancer arising at least 30 days after liver transplantation, excluding relapses from prior cancers and donor-derived cancers. We determined the incidence of de novo cancer in the cohort using the Aalen-Johansen estimator, with death and retransplantation as competing risks. We included 389 liver transplant recipients and identified 47 recipients (12%) with de novo cancer after liver transplantation, including 25 recipients with non-melanoma skin cancers. The cumulative incidences at 5 years after liver transplantation for all cancers and non-skin cancers were 10.7% and 4.9%, respectively. De novo cancer after liver transplantation is relatively common, with the majority being non-melanoma skin cancer. Future studies of sufficient size are needed to identify risk factors for de novo cancer after liver transplantation.

Immune checkpoint inhibitors in malignancies after liver transplantation: A systematic review and pooled analysis

BACKGROUND AND AIMS

Treatment of de novo malignancies and recurrent hepatocellular carcinoma with immune checkpoint inhibitors (ICI) in liver transplant recipients (LT) is an attractive strategy that is infrequently pursued because of the lack of strong evidence regarding their safety and efficacy. In this systematic review with pooled analysis, we aimed to assess safety and efficacy of ICI therapy following LT.

METHODS

We performed a systematic search of case reports and series published until January 2022. We included 31 publications reporting a total of 52 patients treated with ICIs after LT and assessed in a pooled analysis the risk of graft rejection and the outcome of ICI therapy.

RESULTS

Acute graft rejection occurred in 15 patients (28.8%) and 7 patients (13.4% of the total cohort) died because of graft loss. Rejection was associated with shorter overall survival (OS) (17.2 months, confidence interval [CI] 12.1-22.2 vs. 3.5 months, CI 1.6-5.4, p < 0.001). Disease control rate was 44.2% (n = 23), and in these patients, OS was longer than in non-responders (26.4 months, CI 20.8-32.0 vs. 3.4 months, CI 2.1-4.7, p < 0.001).

CONCLUSIONS

Observational, off-label experience suggests that treatment with ICI for advanced malignancies in LT recipients might not be discarded a priori. This notwithstanding, ICI treatment in these patients is associated with a substantial risk of graft rejection and mortality. Prospective studies are needed to provide adequate safety and efficacy figures of ICI treatment in this fragile population.

De Novo Malignancy After Liver Transplantation: Risk Assessment, Prevention, and Management-Guidelines From the ILTS-SETH Consensus Conference

De novo malignancies (DNMs) following liver transplantation (LT) have been reported as 1 of the major causes of late mortality, being the most common cause of death in the second decade after LT. The overall incidence of DNMs is reported to be in the range of 3.1% to 14.4%, and the incidence is 2- to 3-fold higher in transplant recipients than in age- and sex-matched healthy controls. Long-term immunosuppressive therapy, which is the key in maintaining host tolerance and achieving good long-term outcomes, is known to contribute to a higher risk of DNMs. However, the incidence and type of DNM also depends on different risk factors, including patient demographics, cause of the underlying chronic liver disease, behavior (smoking and alcohol abuse), and pre-existing premalignant conditions. The estimated standardized incidence ratio for different DNMs is also variable. The International Liver Transplantation Society-Spanish Society of Liver Transplantation Consensus Conference working group on DNM has summarized and discussed the current available literature on epidemiology, risk factors, management, and survival after DNMs. Recommendations for screening and surveillance for specific tumors, as well as immunosuppression and cancer-specific management in patients with DNM, are summarized.

Review of Standardized Incidence Ratios (SIR) of non-lymphoid de novo malignancies after liver transplantation: Structured analysis of global differences

INTRODUCTION

De Novo malignancy after liver transplantation (LTx) is the second most common cause of death in adult LTx recipients. The current report identifies differences in Standardized Incidence Ratios (SIR) for various non-lymphoid de novo malignancies by comparing and analyzing post LTx SIR for non-lymphoid de novo malignancies.

MATERIAL AND METHODS

A thorough search of PubMed and Web of Science databases was conducted; 25 publications describing de novo malignancies post-LTx with SIR were identified.

RESULTS

Overall SIR varied from 1.4 to 11.6 (median 2.4). Oropharyngeal/larynx (OPL), lung, colo-rectal, and kidney malignancies were more prevalent with higher SIR (median = 4.4, 1.9, 2.67, 2.5, respectively). Breast and prostate malignancies were also more prevalent with lower SIR (median = 0.9, 1.0, respectively). Pancreatic, central nervous system (CNS), melanoma, rare cancers and Kaposi's sarcoma were less prevalent (except in Italy and Sweden) but had much higher SIR (median = 2.6, 2.4, 2.02, 22.5 and 53.6, respectively). The overall higher SIR values are related to the age of the recipient, length of follow-up, the grouping of different organ systems, inclusion or exclusion of epidermal non-malacotic skin cancers, lymphoid malignancy, and occurrence of rare malignancies including Kaposi's sarcoma.

CONCLUSION

OPL, lung, gastrointestinal, kidney, and bladder malignancies were more prevalent with higher SIR. Breast and prostate cancers were more prevalent with lower SIR. Pancreatic, CNS, melanoma, rare cancers and Kaposi's sarcoma were less prevalent with higher SIR. Age of the recipients, length of follow-up, and rare cancer types influence overall SIR values with some global differences.

Medical care of liver transplant patients

INTRODUCTION

Liver transplantation is a life-changing event for patients and survival following transplantation has improved significantly since the first transplantation in 1967. Following liver transplantation, patients face a unique set of healthcare management decisions including transplantation-specific complications, recurrence of primary liver disease, as well as metabolic and malignancy concerns related to immunosuppression. As more patients with liver disease receive transplantation and live longer, understanding and managing these patients will require not only transplant specialist but also local subspecialist and primary care physicians.

AREAS COVERED

This review covers common issues related to the management of patients following liver transplantation including immunosuppression, liver allograft dysfunction, metabolic complications, as well as routine health maintenance such as immunizations and cancer screening.

EXPERT OPINION

Optimizing medical care for patients following liver transplant will benefit from ensuring all providers, not just transplant specialist, have a basic understanding of the common issues encountered in the post-transplant patient. This review provides an overview of common healthcare concerns and management options for patients following liver transplantation.

DPYD and Fluorouracil-Based Chemotherapy: Mini Review and Case Report

5-Fluorouracil remains a foundational component of chemotherapy for solid tumour malignancies. While considered a generally safe and effective chemotherapeutic, 5-fluorouracil has demonstrated severe adverse event rates of up to 30%. Understanding the pharmacokinetics of 5-fluorouracil can improve the precision medicine approaches to this therapy. A single enzyme, dihydropyrimidine dehydrogenase (DPD), mediates 80% of 5-fluorouracil elimination, through hepatic metabolism. Importantly, it has been known for over 30-years that adverse events during 5-fluorouracil therapy are linked to high systemic exposure, and to those patients who exhibit DPD deficiency. To date, pre-treatment screening for DPD deficiency in patients with planned 5-fluorouracil-based therapy is not a standard of care. Here we provide a focused review of 5-fluorouracil metabolism, and the efforts to improve predictive dosing through screening for DPD deficiency. We also outline the history of key discoveries relating to DPD deficiency and include relevant information on the potential benefit of therapeutic drug monitoring of 5-fluorouracil. Finally, we present a brief case report that highlights a limitation of pharmacogenetics, where we carried out therapeutic drug monitoring of 5-fluorouracil in an orthotopic liver transplant recipient. This case supports the development of robust multimodality precision medicine services, capable of accommodating complex clinical dilemmas.

Prevalence of advanced colorectal neoplasm is higher in liver transplant recipients

BACKGROUND/AIMS

Patients with liver transplantation are at increased risk of developing new malignancy because of the prolonged immunosuppression after transplantation. The aims of this study were to investigate whether advanced colorectal neoplasms occurs more in liver transplant recipients compared to healthy individuals and to evaluate the effect of immunosuppression on advanced colorectal neoplasia.

MATERIALS AND METHODS

This was a retrospective, single-centered, case-control study. We reviewed 348 liver transplant patients who had undergone a colonoscopy after liver transplantation from 1991 to 2012. Healthy controls from asymptomatic individuals who had undergone colonoscopy for screening purposes were randomly selected and reviewed.

RESULTS

Advanced colorectal neoplasms were identified in 17 of the 348 patients (4.9%). The risk of advanced colorectal neoplasia was 3.6 times greater in liver transplant patients (odds ratio [OR] 3.578; 95% confidence interval [CI] 1.578-8.115; p=0.001). The risk of developing colon cancer was 8.4 times higher in transplant patients (OR 8.416; 95% CI 1.808-39.172; p=0.001).

CONCLUSION

Liver transplant recipients were at a high risk of colorectal cancer. Therefore, colonoscopy surveillance after liver transplantation is recommended. Immunosuppressive therapy could facilitate carcinogenesis.

Comprehensive Review on Colorectal Cancer and Transplant

Colorectal cancer (CRC) is a common malignancy worldwide. Some studies suggest that organ recipients are at a higher risk for CRC than the general population. The underlying transplant indications and their inherent risk factors for CRC may drive the variation in incidence rates that are seen in patients receiving different allografts. Recipients with cystic fibrosis are now recognized as a population at high risk for CRC at a young age. Transplant recipients have high mortality following a CRC diagnosis, even if it is detected at an early stage. Certain types of immunosuppression have been shown to accelerate cancer transformation and may contribute to the more aggressive phenotype seen in organ recipients. Given the high incidence and progressive nature of posttransplant CRC, shorter screening intervals with a modality that can detect early-stage polyps may be essential to prevent mortality. Future research is needed to better elucidate the role of immunosuppression in carcinogenesis. This comprehensive review examines CRC risk, screening, and management specific to organ transplant candidates and recipients.

Accelerated Premalignant Polyposis and Second Colon Cancers: Incriminating Immunosuppression, Radiotherapy, and Systemic Chemotherapy Agents

BACKGROUND

Cancer survivors are known to be at increased risk for second primary cancers. In addition, immunosuppression and previous cancer treatments such as radiotherapy and systemic chemotherapy are linked with increased risk of both colonic adenomas and adenocarcinomas.

AIM

We performed a systematic review searching for manuscripts discussing second colon cancers, accelerated polyposis, immunosuppression, radiation, and chemotherapy. We sought to identify a link between immunosuppression and increased risks specific to premalignant polyposis and second colon cancers.

FINDINGS

We identified multiple studies demonstrating associations between radiotherapy, systemic chemotherapy, and immunosuppression with a higher propensity for second colon adenomas and adenocarcinomas. When compared to the general population, these risks were more profound and the rate at which these second malignancies developed was significantly increased.

CONCLUSIONS

We believe that timing for colonoscopic surveillance in these patients should be different from the general population in order to identify promptly these rapidly progressive neoplasms. Screening for second malignancies should be considered early after remission of the primary cancer is documented, especially when a prolonged survival or a cure is anticipated. We also recommend consideration be given to increasing the frequency of colonoscopy in these cohorts. Future studies are required in order to establish the optimal time interval for surveillance colonoscopy in these high-risk individuals.

A Review of Inflammatory Bowel Disease in the Setting of Liver Transplantation

Although inflammatory bowel disease (IBD) rarely arises in the setting of solid organ transplantation, IBD has a higher incidence in this setting than in the general population and poses challenging management issues. The most common association is hepatic orthotopic transplant for primary sclerosing cholangitis. This article discusses IBD in the setting of liver transplantation, including both the development of de novo IBD and the evolution of preexisting IBD posttransplant, as well as management considerations in addressing colorectal cancer risk in this patient population.

Inflammatory bowel disease after liver transplantation for primary sclerosing cholangitis

The course of inflammatory bowel disease (IBD) after liver transplantation (LT) for primary sclerosing cholangitis (PSC) is complex, with several IBD-, PSC-, and transplant-related factors interplaying with each other. Approximately one-third of patients with known IBD improve, and one-third paradoxically worsen, after LT for PSC. Active IBD, discontinuation of 5-aminosalicylates (5-ASA) at time of LT and tacrolimus-based immunosuppression may be associated with an unfavorable course of IBD after LT. Approximately 14-30% patients with PSC may develop de novo IBD 10 years after LT. LT confers a high risk of pouchitis after ileal pouch-anal anastomosis, although it may not be higher than baseline rates for PSC patients. The risk of colorectal cancer continues to be high after LT for PSC, and is higher in this cohort of patients with PSC-IBD, compared with patients undergoing LT for other indications. IBD does not adversely affect patient survival after LT, although the risk of recurrent PSC in the allograft may be higher in patients with IBD and an intact colon at time of LT. Standard therapy with 5-ASA and/or azathioprine may be appropriate for treatment of active IBD after LT and maintenance of remission. Anti-tumor necrosis factor-α agents are effective, but should be used with caution because of high risk of adverse events. The management of IBD after LT requires close coordination between transplant hepatologists and IBD experts.

How can we treat a patient with liver cirrhosis (hepatitis C virus), hepatocellular carcinoma, and synchronous colon cancer?

INTRODUCTION

The coexistence of liver cirrhosis with hepatocellular carcinoma (HCC) and colon cancer (Ca), which is a rare clinical condition, was treated in a liver transplant recipient.

PATIENTS AND METHODS

A 46-year-old man, diagnosed incidentally during an ultrasound (US) examination with a 3.5-cm HCC in segment VII related to chronic hepatitis C virus (HCV), was referred for liver resection. He underwent a laparoscopic protocol evaluation for liver cirrhosis. Liver appearance and biopsy of the left lobe showed Child B/C liver cirrhosis. Because he fulfilled the Milan criteria, we suggested an orthotopic liver transplantation (OLT). During protocol colonoscopy, we discovered an ulcerative sigmoid colon Ca. Three weeks after completing the pre-OLT assessment he underwent an OLT and was discharged home on day 9 on an immunosuppressive regimen of Everolimus, Myfortic, and Prezolone. Two months after transplantation, the patient underwent a sigmoidectomy and for nearly 1 month thereafter received chemotherapy for colon Ca (6 cycles of FOLFOX:Folinic Acid+Fluorouracil+Oxaliplatin). One and a half years after OLT, patient was in good condition but presented with an increased alpha fetoprotein (a-FP) without other findings. A couple of months later we discovered a colon Ca recurrence and 3 small liver metastases. Patient underwent a bowel resection with Hartmann's procedure. Almost immediately after the last operation, he was found to suffer multiple myeloma. He underwent chemotherapy for both malignancies with good responses, but a few months later died of severe sepsis.

DISCUSSION

The relevant literature regarding treatment of liver cirrhosis complicated with HCC and synchronous colon Ca reveals poor and controversial outcomes. Our patient underwent chemotherapy immediately after colon resection in the presence of with a good functioning liver. Although his condition was satisfactory after OLT, the optimal treatment of such complicated patients is as yet uncertain.

Burden of de novo malignancy in the liver transplant recipient

Recipients of liver transplantation (LT) have a higher overall risk (2-3 times on average) of developing de novo malignancies than the general population, with standardized incidence ratios ranging from 1.0 for breast and prostate cancers to 3-4 for colon cancer and up to 12 for esophageal and oropharyngeal cancers. Aside from immunosuppression, other identified risk factors for de novo malignancies include the patient's age, a history of alcoholic liver disease or primary sclerosing cholangitis, smoking, and viral infections with oncogenic potential. Despite outcome studies showing that de novo malignancies are major causes of mortality and morbidity after LT, there are no guidelines for cancer surveillance protocols or immunosuppression protocols to lower the incidence of de novo cancers. Patient education, particularly for smoking cessation and excess sun avoidance, and regular clinical follow-up remain the standard of care. Further research in epidemiology, risk factors, and the effectiveness of screening and management protocols is needed to develop evidence-based guidelines for the prevention and treatment of de novo malignancies.