3470 - Role of Intraoperative Radiotherapy in Hepatocellular Carcinoma Following Narrow-Margin Hepatectomy: A Single Institutional Long-Term Follow Up Analysis
Presenter(s)
M. Li1, Y. Zhai1, B. Chen1, W. Yanling1, L. Wang2, F. Wu2, S. Wang1, Y. Liu1, Y. W. Song1, N. Li3, Y. Tang1, H. Jing1, H. Fang1, N. Lu1, S. Qi1, Z. Yang1, S. Y. Chen1, Y. X. Li1, J. Wu2, and Q. Feng1; 1Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China, 2Department of Hepatobiliary Surgery, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China, 3Department of Radiobiology, Shanxi Province Cancer Hospital/ Shanxi Hospital Affiliated to Cancer Hospital, Chinese Academy of Medical Sciences/Cancer Hospital Affiliated to Shanxi Medical University, Taiyuan, China
Purpose/Objective(s): Surgical resection is the primary treatment option for hepatocellular carcinoma (HCC); however, narrow-margin hepatectomy is associated with a high rate of recurrence and death. This study aims to investigate the long-term efficacy and safety of intraoperative radiotherapy (IORT) for patients with HCC after narrow-margin (<1cm) hepatectomy.
Materials/Methods: A retrospective analysis was performed on patients with hepatocellular carcinoma who underwent IORT following narrow-margin hepatectomy at our hospital between November 2009 and February 2019. IORT was delivered at a single fraction with doses ranging from 12 to 17 Gy targeting the narrow margins, utilizing 6 MeV or 9 MeV electron beams. Overall survival (OS) and disease-free survival (DFS) were calculated from the date of surgical resection using the Kaplan-Meier method. Univariate analysis of the prognosticators for OS and DFS was performed using the Cox proportional hazards model. Toxicities were graded according to the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0.
Results: A total of 64 patients were enrolled, with a median age of 57 years (range, 34-75 years). The median follow-up duration was 83.3 months (range, 19.6-151.9 months). A median dose of 15 Gy was prescribed at the 90% isodose delivered with a median treatment depth of 0.9cm (range, 0.8-1.2 cm). The 1-year, 3-year, 5-year, 7-year and 10-years OS rates were 90.4%, 80.6%, 75.5%, 69.9% and 47.6%, respectively. The 1-year, 3-year, 5-year, 7-year and 10-years DFS rates were 77.8%, 68.1%, 59.6%, 57.6% and 38.4%, respectively. Additionally, univariate analysis suggested that the preoperative serum alpha-fetoprotein (AFP) <400ng/mL was associated with improved OS (HR=3.52, 95%CI=1.45-8.15, P=0.005). Recurrence events were recorded in twenty-eight patients (43.8%) with no cases of marginal recurrence. For the first recurrence, twenty-two patients experienced intrahepatic recurrences, two developed extrahepatic recurrences, and four progressed with both intrahepatic and extrahepatic recurrence. The 1-year, 3-year, 5-year, 7-year and 10-years rates of intrahepatic recurrence free survival were 81.0%, 72.8%, 62.6%, 60.7% and 45.5%, respectively. The 1-year, 3-year, 5-year, 7-year and 10-years rates of extrahepatic recurrence free survival were 93.6%, 92.0%, 90.4%,90.4% and 90.4%, respectively. None of the enrolled patients were diagnosed as radiation-induced liver disease during follow-up and the incidence of grade 3 toxicities was low (4.7%, raised alanine aminotransferase and gamma-glutamyl transferase). No grade 4-5 toxicities or 30-day operative mortality were observed.
Conclusion: For patients undergoing narrow-margin hepatectomy, IORT is effective and safe, demonstrating favorable long-term survival and tolerable toxicities.