Solid serous adenoma of the pancreas: an uncommon but important entity

Serous cystic neoplasms of the pancreas have currently five recognized subtypes: serous microcystic adenoma, serous oligocystic ill-demarcated adenoma, solid serous adenoma, von Hippel-Lindau-associated cystic neoplasm, and serous cystadenocarcinoma. Although these neoplasms are histologically similar they may differ in location, gross appearance and biology. Solid serous adenoma of the pancreas is by far the rarest subtype with only nine cases published thus far. In this review, we will discuss clinical features, imaging characteristics and histopathological findings, considering in particular (1) difficulties in preoperative diagnosis; and (2) relevant immunohistochemical analysis. After analyzing the literature, including one case from our Department, we can conclude that there is enough evidence to support that solid serous adenomas of the pancreas is a solid variant of serous cystadenomas. To date no malignant transformation is reported so far and therefore, to our knowledge, all patients are alive and without recurrence. Incidence is generally around seventh decade of life with no gender preference. Preoperative diagnosis is difficult to establish but magnetic resonance cholangiopancreatography may be useful. Given benign nature of this solid variant conservative surgery is recommended. It is definitively a rare entity but oncologic surgeons should be aware of this neoplasm in order to make a correct preoperative diagnosis that will ultimately result in more conservative surgeries.