Utilization of Immunotherapy as a Neoadjuvant Therapy for Liver Transplant Recipients with Hepatocellular Carcinoma

Background: Hepatocellular carcinoma (HCC) is widely recognized as the predominant type of primary liver malignancy. Orthotopic liver transplantation (OLT) has emerged as a highly effective treatment option for unresectable HCC. Immunotherapies as neoadjuvant options are now being actively investigated in the transplant oncology era to enhance outcomes in patients with HCC. Here, we report our experience with patients with HCC who had received Immune Checkpoint Inhibitors (ICPI) prior to curative OLT. Methods: This was a retrospective cohort that included patients with HCC who received ICPI prior to OLT at a single institution from January 2019 to August 2023. Graft rejection was assessed and reported along with the type of ICPI, malignancy treated, and the timing of ICPI in association with OLT. Results: During this cohort period, six patients with HCC underwent OLT after neoadjuvant ICPI. All patients were male with a median age of 61 (interquartile range: 59-64) years at OLT. Etiology associated with HCC was viral (N = 4) or Non-alcoholic steatohepatitis, NASH (N = 2). Tumor focality was multifocal (N = 4) and unifocal (N = 2). Lymphovascular invasion was identified in four patients. No perineural invasion was identified in any of the patients. All patients received ICPI including atezolizumab/bevacizumab (N = 4), nivolumab/ipilimumab (N = 1), and nivolumab as monotherapy (N = 1). All patients received either single or combined liver-directed/locoregional therapy, including transarterial chemoembolization (TACE), Yttrium-90 (Y90), stereotactic body radiotherapy (SBRT), and radiofrequency ablation (RFA). The median washout period was 5 months. All patients responded to ICPI and achieved a safe and successful OLT. All patients received tacrolimus plus mycophenolate as immunosuppressant (IS) therapy post-OLT and one patient received prednisone as additional IS. No patient had clinical evidence of rejection. Conclusions: This cohort emphasizes the success of tumor downstaging by ICPI for OLT when employed as the neoadjuvant therapy strategy. In addition, this study illustrated the importance of timing for the administration of ICPI before OLT. Given the lack of conclusive evidence in this therapeutic area, we believe that our study lays the groundwork for prospective trials to further examine the impact of ICPI prior to OLT.