Malignant neoplasms of the pancreas are rare in childhood. These lesions may be functioning or nonfunctioning, and appear to have a better prognosis than in the adult when radical operations are performed. Three additional cases of childhood pancreatic malignancy are presented. The first case demonstrates how inadequate operation for a benign cystadenoma resulted in postoperative complications, recurrence, and subsequent sarcomatous degeneration. In the second case, intraoperative mesovenoportography aided in determining resectability of a carcinoma of the head of the pancreas, for which pancreatoduodenectomy was successfully performed. The second and third cases (both carcinomas) show how electron microscopy can differentiate islet cell lesions from other cellular origins of pancreatic cancer.