Radiotherapy for carcinoma of the pancreas.

Many carcinomas of the pancreas are locally unresectable but have no gross evidence of metastases at diagnosis. Initial experience showed the disease to be relatively unresponsive to radiotherapy. However, results from Duke University and the Mayo Clinic led to the study of the disease by the Gastrointestinal Tumor Study Group (GITSG). The GITSG studies showed that radiotherapy and 5-fluorouracil chemotherapy in a relatively nonaggressive regimen prolonged the survival following apparent curative resection of carcinoma of the pancreas. In addition, for locally unresectable disease, GITSG showed that both chemotherapy and radiotherapy were necessary for the best results. However, even with optimal therapy the median survival in this group of patients is no more than 1 year. Many studies of specialized radiation techniques have also been evaluated. These included preoperative radiotherapy and chemotherapy, use of radiosensitizers, particle irradiation, interstitial irradiation, intraoperative irradiation, and hyperthermia. Results of these studies have not shown major improvement over the GITSG experience. In general, patients with pancreatic cancer who are irradiated appear to do better than those who are not. No other single modality has been more effective. It is therefore hoped that successful chemotherapeutic agents or other modalities can be developed and combined with the limited efficacy of radiotherapy.