Young–age‐onset pancreatoduodenal carcinoma in Shwachman–Diamond syndrome

Shwachman–Diamond syndrome, which is characterized by pancreatic fatty degeneration, skeletal growth retardation, and hematological dysfunction, is a congenital disease caused by SBDS gene mutations. Although hematological disorders often accompany this syndrome, carcinomas associated with this syndrome have not been reported except in one breast cancer and one moderately differentiated pancreatic cancer case. We report on an autopsy of a 24‐year‐old case of pancreatoduodenal carcinoma in Shwachman–Diamond syndrome. The histology of the tumor was undifferentiated carcinoma, which seems to have originated from either the pancreatic duct or the duodenal epithelium. The tumor was intermingled with two pathological changes characteristic of Shwachman–Diamond syndrome: fatty degeneration of the pancreas and inflammation of the villous stroma of the duodenum. Considering that SBDS protein regulates mitosis and its suppression causes genomic instability, this case might provide an example of carcinogenesis based on genomic instability, together with degenerative changes and chronic inflammation, at a very young age.