Outcomes for Salvage Abdominal Stereotactic Body Radiation Therapy for Hepatocellular Carcinoma after Liver Transplantation

Abstract

<h3>Purpose/Objective(s)</h3> While orthotopic liver transplantation (OLT) is considered curative for most hepatocellular carcinoma (HCC) patients, recurrence can occur in 10-20% of these patients. Data has shown stereotactic body radiation therapy (SBRT) to be safe and effective as treatment for primary HCC, however few studies have investigated the safety and efficacy of SBRT as treatment for HCC after OLT. The aim of this study is to evaluate the safety and efficacy of intra-abdominal salvage SBRT for HCC in patients who previously underwent OLT. <h3>Materials/Methods</h3> A retrospective chart review of a single, large institution was conducted to identify patients who received intra-abdominal SBRT as treatment for recurrent HCC after OLT from 1/1/2013 to 12/1/2021. Clinical safety was measured by the National Cancer Institute's Common Terminology Criteria for Adverse Events (CTCAE) v5.0 for grading adverse events, Child-Turcott-Pugh (CTP) score, and Albumin-Bilirubin (ALBI) grade for HCC. Dosimetric analysis was performed. Efficacy was measured by local control (LC) and objective response using modified Response Evaluation Criteria in Solid Tumors (mRECIST). The Kaplan-Meier method was used to evaluate overall survival (OS) and progression free survival (PFS). <h3>Results</h3> 18 lesions, treated among 15 patients were identified that received intra-abdominal SBRT for HCC recurrence after OLT. Nine patients were male, median age was 62 (interquartile range 52 to 80). The American Joint Committee on Cancer stage at diagnosis was most often T1N0M0 (n=8, 53%) or T2N0M0 (n=5, 33%). The most common etiology for HCC diagnosis was hepatitis C virus (n=9, 56%). Median CTP and ALBI scores at baseline were 5 (range 5 to 11) and -3.02 (range -3.36 to -1.35), respectively. Median change in CTP score from baseline to CTP at 3, 6, and 12 months was 0.00, 1.00, and 1.00. Median change in ALBI score from baseline to at 3, 6, and 12 months was 0.14, 0.40, and 0.42. The median treatment dose was 4750 cGy (interquartile range 500 cGy), all patients received 5 fractions. There was no grade 3 or above CTCAE toxicities. During 6 (33%) SBRT treatments, patient experienced grade 1 or 2 CTCAE toxicity with nausea, emesis, or fatigue. Local control was achieved in 94% of lesions (n=17). Local treatment response was: 11 (61.2%) complete response, 5 (27.8%) partial response, 1 (5.5%) stable disease, and 1 (5.5%) progressive disease. After median follow up of 19.2 months, 8 patients (53%) were deceased and 7 (47%) had no evidence of disease progression. OS was 100% at 6 months and 60.8% at 12 months. PFS was 92.9% at 6 months and 60.9% at 12 months. No dosimetric factor was found to predict for increased toxicity. <h3>Conclusion</h3> For patients with HCC after OLT, SBRT appears to be a safe and effective treatment modality, as no patients experienced significant toxicities and the majority had complete treatment response.