Value of intraoperative radiotherapy in locally advanced rectal cancer

PURPOSE: This study was designed to analyze the results of a multimodality treatment using preoperative radiotherapy, followed by surgery and intraoperative radiotherapy in patients with primary locally advanced rectal cancer. METHODS: Between 1987 and 2002, 123 patients with initial unresectable and locally advanced rectal cancer were identified in our prospective database, containing patient characteristics, radiotherapy plans, operation notes, histopathologic reports, and follow-up details. An evaluation of prognostic factors for local recurrence, distant metastases, and overall survival was performed. RESULTS: All patients were treated preoperatively with a median dose of 50 Gy radiotherapy. Surgery was performed six to ten weeks after radiotherapy. Twenty-seven patients were treated with intraoperative radiotherapy because margins were incomplete or ≤2 mm. Postoperative mortality was 2 percent. The median follow-up of all patients was 25.1 months. The overall five-year local control was 65 percent and the overall five-year survival was 50 percent. Positive lymph nodes and incomplete resections negatively influenced local control and overall survival. Intraoperative radiotherapy improved five-year local control (58 vs. 0 percent, P = 0.016) and overall survival (38 vs. 0 percent, P = 0.026) for patients with R1/2 resections. CONCLUSIONS: The presented multimodality treatment is feasible with an acceptable mortality and a five-year overall survival of 50 percent. Addition of intraoperative radiotherapy for patients with a narrow or microscopic incomplete resection seems to overrule the unfavorable prognostic histologic finding.