Distribution of somatostatin in pancreatic ductal adenocarcinoma remodels the normal pattern of the protein during foetal pancreatic development: an immunohistochemical analysis.

Aim: To determine the immunoreactivity of somatostatin during the development of the human fetal pancreas and pancreatic ductal adenocarcinoma, given that, somatostatin-positive cells were demonstrated either into its embryonic anlage or into pancreatic cancer.

Methods: Tissue sections from 15 pancreatic fetal specimens, and an equal number of ductal adenocarcinoma specimens were assessed.

Results: The density of positive cells in the primitive exocrine ductal epithelium and endocrine epithelium was significantly different from the relevant density in the neoplastic pancreatic tissue of mixed (ductal-endocrine) and pure ductal type (P1=0.021 P2=0.001, P3<0.0001, P4=0.003 respectively). The above values were estimated from the 8th to 10th week. There was no significant difference in the density of positive cells in the mantle zone of the islets from the 13th to the 24th week, and the neoplastic tissue of mixed (P5=0.16) and pure ductal type (P6=0.65).

Conclusion: The immunostaining for somatostatin identifies a subgroup of pancreatic ductal adenocarcinomas with a neuroendocrine component, (initially considered as pure ductal tumors), and mixed ductal and neuroendocrine tumors. This pattern of expression in neoplasms recapitulates the normal pattern during the embryonal development of the organ, raising the question of therapeutic efficacy of somatostatin and analogues as monotherapy in pancreatic cancer management.