S. Krishnamurthy et al., PANCREATIC ACINAR CELL CLUSTERS IN PEDIATRIC GASTRIC-MUCOSA, The American journal of surgical pathology, 22(1), 1998, pp. 100-105
Although clusters of pancreatic acinar cells (CPACs) have been reporte
d in gastric mucosa of adults, they have not been described in childre
n. We reviewed 283 pediatric gastric (239 antral and 44 corpus) mucosa
l biopsies during a 2-year period and detected CPACs in 10 antral biop
sy samples. These biopsy samples were stained immunohistochemically fo
r pancreatic exocrine markers (trypsin, chymotrypsin, alpha-amylase, a
nd lipase) and a panel of regulatory substances (insulin, glucagon, so
matostatin, pancreatic polypeptide, gastrin, and serotonin). Double im
munostaining for colocalization of chromogranins and trypsin as well a
s mucin and trypsin also were performed on all cases. CPACs were seen
in antral mucosa in a background of either normal or minimally inflame
d mucosa, without any atrophy or metaplasia, and were positive for all
pancreatic exocrine markers. Stray chromogranin-positive cells in the
CPACs were also immunopositive for somatostatin, gastrin, or serotoni
n. All CPACs showed a few hybrid (amphicrine) cells that coexpressed b
oth chromogranin and trypsin. In one case, ultrastructural examination
showed such cells to contain both zymogen and neurosecretory granules
. Although the presence of CPACs exclusively in the antrum is most lik
ely the result of a sampling bias, the presence of hybrid cells with a
n amphicrine phenotype suggests that CPACs probably result from an abe
rration of stem cell differentiation.