Over a 21 year period, 245 cases of cancer of the pancreas were operated upon and followed-up at UCLA Hospital. A further 34 cases of periampullary tumor were treated by partial or total pancreatectomy. Apparent clearance of tumors at the time of pancreaticoduodenectomy that was confirmed by subsequent histopathology resulted in a patient survival time of 20.3 months as compared with a figure of 12.9 months when the pathological examination revealed tumor in a resection margin, although the surgeon believed that excision had been complete at the time of the operation. Frozen section examination of resection margins is therefore mandatory. The result of performing a pancreaticoduodenectomy in which tumor was seen to be left behind was a survival time of only 6.8 months, which is similar to the survival time of 6.2 months following a palliative biliary bypass. Pancreaticoduodenectomy in patients over the age of 70 resulted in an average survival of only 7.6 months. Of patients having a palliative biliary bypass alone, 13% required subsequent reoperation to bypass distressing duodenal obstruction. A duodenal bypass should therefore be a routine concomitant of a biliary bypass. Total pancreatectomy with duodenectomy for pancreatic cancer gave an increased average survival of 26 months, and it is likely that the frequency of performance of this operation will increase.