ovarian metastase of pancreaticobiliary tract adenocarcinoma

Metastatic mucinous carcinomas in the ovary are readily recognized when they show characteristic features, including bilateral involvement, only moderate tumor size, surface and superficial cortical involvement, nodular growth, and an infiltrative pattern.

However, it is well established that some metastatic mucinous carcinomas can simulate primary ovarian mucinous tumors grossly and microscopically.

Metastatic pancreaticobiliary tract adenocarcinomas present a particular diagnostic challenge due to their ability to exhibit borderline-like and cystadenomatous growth patterns, which can be misinterpreted as underlying primary ovarian precursor tumors and can be erroneously used to support interpretation of the carcinomatous components as arising from these purported precursors within the ovary.

Frequent bilateral ovarian involvement, moderate tumor size, nodularity, and infiltrative patterns are useful features for identifying these ovarian tumors as metastatic.

However, many tumors exhibit borderline-like and cystadenomatous patterns that, when dominant and combined with synchronous presentation, make recognition as metastases an ongoing challenge.

Loss of Dpc4 (SMAD4) expression provides the most useful immunohistochemical evidence for establishing the pancreaticobiliary tract as the most likely source of these metastatic mucinous carcinomas in the ovary.

References

 Ovarian metastases of pancreaticobiliary tract adenocarcinomas: analysis of 35 cases, with emphasis on the ability of metastases to simulate primary ovarian mucinous tumors. Meriden Z, Yemelyanova AV, Vang R, Ronnett BM. Am J Surg Pathol. 2011 Feb;35(2):276-88.PMID: 21263249