Transplantation for colorectal metastases: on the edge of a revolution

New Insights in the Setting of Transplant Oncology

Background and Objectives: Liver transplantation (LT) is the best strategy for curing several primary and secondary hepatic malignancies. In recent years, growing interest has been observed in the enlargement of the transplant oncology indications. This paper aims to review the most recent developments in the setting of LT oncology, with particular attention to LT for unresectable colorectal liver metastases (CRLM) and cholangiocellular carcinoma (CCA). Materials and Methods: A review of the recently published literature was conducted. Results: Growing evidence exists on the efficacy of LT in curing CRLM and peri-hilar and intrahepatic CCA in well-selected patients when integrating this strategy with (neo)-adjuvant chemotherapy, radiotherapy, or locoregional treatments. Conclusion: For unresectable CCA and CRLM management, several prospective protocols are forthcoming to elucidate LT’s impact relative to alternative therapies. Advances in diagnosis, treatment protocols, and donor-to-recipient matching are needed to better define the oncological indications for transplantation. Prospective, multicenter trials studying these advances and their impact on outcomes are still required.

Liver Transplantation as a Curative Approach for Patients With Nonresectable Colorectal Liver Metastases

OBJECTIVES

Liver transplant is emerging as a potential treatment option for patients with isolated colorectal liver metastasis. In this review article, we analyzed the published literature on liver transplant outcomes in such patients.

MATERIALS AND METHODS

Four prospective studies documenting the clinical outcomes in patients with colorectal liver metastasis who underwent liver transplant were analyzed to study the feasibility of liver transplant in such patients.

RESULTS

The SECA-II trial demonstrated the highest overall survival of 100%, 83%, and 83% at 1, 3, and 5 years, respectively, and disease-free survival of 53%, 44%, and 35%, respectively, with a narrow inclusion criterion. Conversely, extended criteria for selection and donors in arm D of the same trial resulted in median overall survival and disease-free survival of 18 and 4 months, respectively.

CONCLUSIONS

Liver transplant provided more prolonged overall survival compared with other therapeutic modalities. Patients with isolated colorectal liver metastasis of less aggressive biology, good performance status, at least 6 weeks of chemotherapy, low clinical risk scores, and negative nodal disease should be considered for patient selection. Moreover, exclusion criteria consisting of patients with the right-sided primary tumor, less than 3 years to liver transplant after diagnosis, and elevation of carbohydrate antigen (CA19-9) in the presence of BRAF mutation should be explored.

Expanding Indications of Liver Transplantation in Spain: Consensus Statement and Recommendations by the Spanish Society of Liver Transplantation

BACKGROUND

The number of patients awaiting liver transplantation (LT) in Spain has halved from 2015 to 2019 due to the reduction of candidates with hepatitis C and the successful implementation of nonheart beating donation programs across the country. The Spanish Society for Liver Transplantation has committed to take advantage of this situation by developing consensus around potential areas to expand the current indications for LT. The consensus group was composed of 6 coordinators and 23 expert delegates, each one representing an LT institution in Spain.

METHODS

A modified Delphi approach was used to identify areas to expand indications for LT and to build consensus around paramount aspects, such as inclusion criteria and waitlist prioritization within each area. The scientific evidence and strength of recommendations were assessed by the "Grading of Recommendations Assessment, Development, and Evaluation" system.

RESULTS

The consensus process resulted in the identification of 7 potential areas to expand criteria in LT: recipient's age, hepatocellular carcinoma, alcoholic hepatitis, acute-on-chronic liver failure, hilar and intrahepatic cholangiocarcinoma, and unresectable liver metastases of colorectal cancer.

CONCLUSIONS

We present the main recommendations issued for each topic, together with their core supporting evidence. These recommendations may allow for expanding criteria for LT homogenously in Spain and may provide a guidance to other countries/institutions facing a similar scenario.

Liver Transplantation for Colorectal and Neuroendocrine Liver Metastases and Hepatoblastoma. Working Group Report From the ILTS Transplant Oncology Consensus Conference

Liver transplantation (LT) for unresectable colorectal liver metastases has long been abandoned because of dismal prognoses. After the dark ages, advances in chemotherapy and diagnostic imaging have enabled strict patient selection, and the pioneering study from the Oslo group has contributed to the substantial progress in this field. For unresectable neuroendocrine liver metastases, LT for patients who met the Milan criteria was able to achieve excellent long-term outcomes. The guidelines further adopted in the United States and Europe were based on these criteria. For hepatoblastoma, patients with unresectable and borderline-resectable disease are considered good candidates for LT; however, the indications are yet to be defined. In the budding era of transplant oncology, it is critically important to recognize the current status and unsolved questions for each disease entity. These guidelines were developed to serve as a beacon of light for optimal patient selection for LT and set the stage for future basic and clinical studies.

Predicting liver metastases growth patterns: Current status and future possibilities

Colorectal cancer is highly incident worldwide and presents a health burden with elevated mortality rate despite prevention, detection, and treatment, mainly due to metastatic liver disease. Histological growth patterns of colorectal cancer liver metastases have emerged as a reproducible prognostic factor, with biological implications and therapeutic windows. Nonetheless, the histological growth patterns of colorectal cancer liver metastases are only known after pathological examination of a liver resection specimen, thus limiting the possibilities of pre-surgical decision. Predicting the histological growth pattern of colorectal cancer liver metastases would provide valuable information for patient-tailored medicine. In this article, we perform a review of the histological growth patterns and their implications, with a focus on the possibilities for their prediction.

Liver transplantation for unresectable malignancies: Beyond hepatocellular carcinoma

Indications for liver transplantation have expanded over the past few decades owing to improved outcomes and better understanding of underlying pathologies. In particular, there has been a growing interest in the field of transplant oncology in recent years that has led to considerable developments which have pushed the boundaries of malignant indications for liver transplantation beyond hepatocellular carcinoma (HCC). In this article, we review and summarise the published evidence for liver transplantation in non-HCC primary and metastatic liver malignancies and highlight ongoing clinical trials that address unresolved questions therein. We also examine the current technical, immunological and oncological challenges that face liver transplantation in this growing field and explore potential approaches to overcome these barriers.

Pushing the limits of liver surgery for colorectal liver metastases: Current state and future directions

Liver surgery for the treatment of colorectal liver metastases is the standard treatment in a dynamic surgical field with many variables that should be considered in a curative intent scenario. Hepatectomy for colorectal liver metastases has undergone constant changes over the last 30 years, including indications until the need for rescue procedures of recurrent and advanced diseases as well as minimally invasive surgery. These advancements in liver surgery have not only resulted from overall improvements in the surgical field but have also resulted from a better understanding of the biological behavior of the disease, liver regeneration, and homeostasis during and after surgery. Improvements in anesthesiology, intensive care medicine, radiology, and surgical devices have correlated with further advancements of hepatectomies. Moreover, changes are still forthcoming, and both fields of augmented reality and artificial intelligence will likely have future contributions in this field in regard to both diagnoses and the planning of procedures. The aim of this editorial is to emphasize several aspects that have contributed to the paradigm shifts in colorectal liver metastases surgery over the last three decades as well as to discuss the factors concerning patient selection and the technical aspects of liver surgery. Finally, this editorial will highlight the promising new features of this surgery for diagnoses and treatments in this field.