Treatment of the patient with adenocarcinoma of unknown origin

One hundred sixty-two patients with adenocarcinoma of undertermined origin were treated with 213 chemotherapeutic regimens, primarily 5-FU by intensive course. Objective response was obtained with 12% of these regimens and was maintained by a median time of 3.5 months and a mean of 9 months. Regimens producing a response rate of 15% or greater included 5-FU alone, 5-FU in combination with BCNU, and mitomycin C. Those patients achieving objective response had a significantly longer survival period than those failing to respond. Necropsy examinations revealed the greatest proportion of patients presenting with adenocarcinoma of unknown origin to have their primary neoplasms in the pancreas.