Intraoperative Radiation Therapy for Unresectable Pancreatic Cancer

ABSTRACT

PURPOSE: We wanted to evaluate the clinical effectiveness of intraoperative radiation therapy (IORT) in combination with external beam radiation therapy (EBRT) for treating unresectable or metastatic pancreatic cancer. METHODS: From August 1993 to July 2007, 28 patients with unresectable or metastatic pancreatic cancer received IORT (median 20 Gy) combined with or without EBRT (median 50.4 Gy). Eighteen patients were treated with IORT followed by EBRT, and 10 patients were treated by IORT alone. Eighteen patients underwent explolaparotomy and 10 patients underwent bypass surgery. RESULTS: The 1-year overall survival rate (OS) and the median survival time of all 28 patients were 21.4% and 7.5 months, respectively. The 1-year OS and median survival time for the clinical stage III patients were 33.3% and 10.2 months, respectively, and they were 7.7% and 5.1 months for the clinical stage IV patients, respectively (p=0.007). Univariate analyses revealed that the stage, chemotherapy and tumor volume were the significant prognostic factors for OS. The patients treated with IORT combined with EBRT had a more favorable 1-year local control rate than that of those patients treated with IORT alone (88.9% vs. 50.0, respectively, p=0.009). But the significant improvement in local control did not translate into a survival benefit. The addition of EBRT was an independent prognostic factor for improving the local control rate. The operative mortality was 0%. CONCLUSION: IORT combined with EBRT is considered to be effective in achieving local control and palliation for patients with unresectable or metastatic pancreatic cancer. Further, IORT seems to be safe and it does not increase the mortality or the incidence of surgical wound infection.