Adjuvant radiotherapy in resectable pancreatic carcinoma

Pancreatic cancer is a near fatal disease. External beam radiotherapy and intraoperative radiation therapy (IORT) has been proposed with the aim to improve clinical outcome in resectable tumors. The aim of this study is to assess the feasibility and outcome in patients with cT1-3 pancreatic cancer, treated with surgery, external beam radiotherapy and IORT.

From 1990 to 1996, 17 patients with clinical stage T1-3N0-1M0 adenocarcinoma of the head of the pancreas were treated with pancreatectomy and pre- (nine patients: 5 Gy), intra- (all patients: 10 Gy) and post-operative (all patients: 50 Gy) radiotherapy. The pathologic T stages were: 4 pT2 and 13 pT3. The pathologic N stages were: 9 pN0 and 8 pN1. Minimum follow-up in living patients was 60 months.

No perioperative mortalities were recorded. Two patients showed postoperative morbidity (11.8%) which required a subsequent laparotomy. The disease-free survival at 1, 3 and 5 years was 41, 23 and 18%, respectively (median: 9 months). The overall survival at 1, 3 and 5 years was 70%, 41% and 18%, respectively (median: 17.5 months). Three patients developed local failure (17.6%) and 12 patients showed distant metastases (70.6%). Univariate analysis (logrank) showed: a significant correlation between both N-stage and retroperitoneal involvement (RPI) with local control (N-stage: P=0.0155; RPI:P =0.0295), a significant correlation between maximum tumor size and metastases-free survival (P=0.0167) and overall survival (P=0.0241); the female gender was another predictor of prolonged survival (P= 0.0465). Multivariate analysis (Cox) showed a significant impact of N-stage and retroperitoneal involvement on local control and also a significant correlation between perineural involvement and tumor diameter with metastases-free survival.

These results are similar to those of other published series and suggest that this approach is feasible with acceptable local control and survival, especially in patients with small tumors (<2.5 cm: 5 year survival=33.3%) and in female patients (5 year survival=30%). Due to the impact of gender, tumor diameter and N stage on prognosis, in the design of future trials a stratification of patients based on these categories should be considered. The search of effective chemotherapeutic agents is required, to reduce the high incidence of distant metastases, especially in larger tumors.