Treatment of probable subclinical liver metastases and gross pancreatic carcinoma with hepatic artery 5-fluorouracil infusion and radiation therapy.

Since subclinical hepatic metastases are frequently present at time of diagnosis of pancreatic carcinoma, any meaningful effort to improve survival must include 'prophylactic' liver therapy in addition to treatment of the pancreatic primary. We report the results of a prospective, unrandomized clinical trial of a 2-week liver and pancreas infusion (by hepatic artery) of 5-fluorouracil (5-FU) and pancreatic irradiation to 50-60 Gy, combined with prophylactic irradiation of the liver with approximately 20 Gy. Of 21 evaluable patients, 17 completed therapy without excessive toxicity and had a median survival of 50 weeks. Contrary to historical controls, the liver in our series was rarely the first site of failure (6%), suggesting that the combination of hepatic artery 5-fluorouracil and 20 Gy liver radiation may suppress subclinical (microscopic) liver metastases without significant hepato-toxicity. When radiation doses to the pancreas were increased above 50 Gy there was improvement in primary tumor control, although failure in the pancreatic bed remained the most common site of failure. Future clinical investigation of this form of combined therapy for eradication of micro-metastasis in the liver, combined with more aggressive local pancreatic therapy, would seem appropriate.