Ultrasonographic follow-up study of small pancreatic cysts of unknown etiology.

The aim of the present project was to evaluate the prognosis of small and asymptomatic cysts of the pancreas which were diagnosed as being nonneoplastic by endoscopic ultrasonography. Eighty-two patients with such cysts had been subjected to ultrasonographic examination every 6 months. Results of follow-up for 3 or more years were obtained in 31 patients. The cysts disappeared in 4 patients and enlarged in 1 patient. The others did not show any morphological changes. The enlarged cyst turned out to be a retention cyst after surgical resection. Our endoscopic ultrasonographic criteria were effective for small nonneoplastic cysts of the pancreas, and most of these cysts appeared to be nonprogressive.