Pancreatic calculi superimposed upon slow growing pancreatic cancer

We report on a 59 year old male patient with cancer of the head of the pancreas, upon which pancreatic calculi were superimposed during the 3 year clinical course. Pancreatic calculi were noted in the main pancreatic duct (MPD) on both computed tomographic scans and ultrasonographs of the abdomen approximately 10 months after the recognizable dilatation of the MPD. Existence of the calculi was confirmed by autopsy. Elemental analysis and infrared spectrophotometry of the calculi demonstrated that the main constituent of the calculi was calcium carbonate. Histopathological examination showed that the pancreatic cancer was moderately differentiated adenocarcinoma. Immunohistochemical studies revealed that pancreatic stone protein (lithostathine) was present in the cytoplasm of tumour cells. In this case, pancreatic cancer progressed to obstruct the MPD unusually slowly, resulting in stagnation of pancreatic secretion and subsequent formation of the calculi.