Nesidioblastosis in adults without insular hyperfunction.

Examination of pancreases from a series of 207 autopsies of adults without either clinical or autopsy evidence of insular hyperfunction showed minimal nesidioblastosis in 36.7%. Ductulo-insular complexes, together with insular cells among the acini, were found in 10.6% of the biopsy specimens. Nesidioblastosis was more frequent in men (61.8%), and the oldest individual was an 84-year-old man. Ductulo-insular complexes and the aggregations of insular cells in the exocrine parenchyma develop asynchronously and may have been initiated by different stimuli. This series did not explain the possible causative factors.