Salvage Ablative Radiation Therapy for Isolated Intraabdominal Recurrences of Hepatocellular Carcinoma

Abstract

<h3>Purpose/Objective(s)</h3> The standard of care for extrahepatic hepatocellular carcinoma (HCC) is a systemic therapy. However, some patients present with limited intra-abdominal disease that might benefit from local ablative radiation therapy (RT) with, or instead of, systemic therapy. This study explores outcomes of ablative RT for isolated intra-abdominal recurrences from HCC. <h3>Materials/Methods</h3> A single-institution retrospective chart review was conducted from 2013 to 2021. Inclusion criteria were any patient with HCC that had limited disease in an abdominal lymph node (LN) or adrenal gland (AG) treated with salvage ablative RT. The primary outcome was local control (LC) in the target lesion. Secondary outcomes were progression-free survival (PFS) and overall survival (OS) from the time of recurrence after completing RT. <h3>Results</h3> 31 patients met inclusion criteria, of which 21 (67.7%) had a recurrence in a LN while 10 (32.2%) had recurrences in an AG. 19 (90%) of LN recurrences were in the portal region. The median time from initial HCC diagnosis to extrahepatic recurrence was 18 months (range 0 to 152 months). Among all patients, 21 patients received immunotherapy (prior, concurrent, or after) in addition to salvage RT. 27 (87.1%) patients received salvage SBRT, and 4 (12.9%) patients received fractionated RT. The median dose was 4500 in 5 fractions. LC, as defined as no progression in target lesion, was 100%. The median PFS, defined by recurrence or death, was 18 months. The median OS was 29 months. There was a statistical difference in OS in patients that received IO and RT vs. RT alone (p=0.038) in favor of RT alone. There was no significant difference in OS for a LN recurrence versus salvage RT for an AG recurrence (p=0.389). <h3>Conclusion</h3> Salvage ablative RT, with or without immunotherapy, can produce meaningful PFS and OS in well-selected patients with limited intra-abdominal extrahepatic recurrence of HCC. This benefit appears the same for LN recurrences and AG metastases and might be independent of immunotherapy. Prospective data are needed to verify these results.