Estrogen receptors in pancreatic tumors

Objectives: Although a potential role for estrogen receptors (ER) in pancreatic tumors has been debated for many years, the importance of the receptors in these neoplasms remains unknown. Even the expression of the 2 ER isoforms, ER-alpha and ER-beta, in histological subtypes of pancreatic neoplasms is controversial. The aim of the present study was to systematically review the available literature about ER expression in pancreatic tumors and to discuss the potential importance of estrogen signaling in them. Methods: We performed a comprehensive literature search and analyzed the results regarding ER expression in pancreatic tumors, with special emphasis on the specificity of the antibodies used for immunohistochemistry. Results: Many articles have been published investigating the expression of ERs in pancreatic tumors, but the results are inconsistent. Moreover, most studies used antibodies that detected only ER-alpha. not ER-beta. Thus, the expression pattern of ER-beta in pancreatic neoplasm remains especially unclear. Conclusions: The lack of detailed studies evaluating the expression of both ER-alpha and ER-beta receptors using isoform-specific antibodies likely contributes to the inconsistency of published results concerning ER expression in pancreatic tumors. Available published evidence suggests that a thorough reexamination of the potential role of ERs in pancreatic neoplasms is warranted.