Evaluation and Management of Liver Transplant Candidates With Prior Nonhepatic Cancer: Guidelines From the ILTS/SETH Consensus Conference

Therapeutic Effects of Anti-PD1 Immunotherapy on Hepatocellular Carcinoma Under Administration of Tacrolimus

BACKGROUND

Liver transplantation (LT) is the treatment of choice for patients with hepatocellular carcinoma (HCC). Recurrence of HCC after LT occurs in 10% to 20% of cases. Preclinical studies to evaluate immune checkpoint inhibitors in conjunction with immunosuppressant treatment in transplant recipients have been lacking. Here, we evaluated the efficacy, safety, and mechanism of programmed cell death-1 (PD1) blockade under tacrolimus treatment in transplant recipients.

METHODS

We used a murine allogeneic skin transplantation model and murine syngeneic subcutaneous and orthotopic HCC models and measured the tumor volume and the change in tumor-infiltrating lymphocytes under PD1 blockade and tacrolimus treatment.

RESULTS

Tacrolimus treatment prolonged allograft survival in the allogeneic transplantation model and enhanced tumor growth in both subcutaneous and orthotopic HCC models. PD1 blockade suppressed tumor growth and lung metastasis in correlation with the number of infiltrating CD8 + T cells. Under tacrolimus treatment, PD1 blockade still resulted in an antitumor effect accompanied by a significant increase in tumor-infiltrating CD8 + T cells, natural killer cells, dendritic cells, and natural killer T cells. Tacrolimus treatment rescued the acceleration of transplant rejection induced by PD1 blockade in the allogeneic transplantation model.

CONCLUSIONS

Our data suggest that treatment with high-dose tacrolimus in conjunction with PD1 blockade has an antitumor effect and reduces transplant rejection in mouse models of allograft skin transplantation and HCC. Thus, these results suggest that a clinical trial of PD1 inhibitors for HCC in LT merits consideration.

The ILTS-SETH Consensus Conference on Extrahepatic Cancer and Liver Transplantation: Paving the Way

The International Liver Transplantation Society and the Spanish Society of Liver Transplantation consensus conference on extrahepatic cancer and liver transplantation (LT) was held on January 28-30, 2021. Working groups were organized to focus on one topic and develop evidence-based recommendations specifically addressing (a) nonhepatic cancer in LT candidates, (b) de novo malignancies after LT, (c) prevention and management of donor-derived malignancies after LT, and (d) nonhepatic cancer in the pediatric population. All consensus conference attendees voted on the recommendations proposed as well as the quality of evidence according to the Grading of Recommendations, Assessment, Development and Evaluation system.