Overlap of microcystic stromal tumor and primary solid pseudopapillary neoplasm of the ovary.

Ovarian microcystic stromal tumors (MCSTs) and ovarian primary solid pseudopapillairy neoplasms (SPNs) are rare ovarian tumors, and recently classified as distinctive variant in the stromal category and miscellaneous tumors respectically in 2009 and 2010. Ever since, there were less then 10 MCSTs and ovarian primary SPNs reported in English literatures. Both of them had something in common, including microscopical morphology, immunohistochemical phenotype, even for the tumorigenesis pathway. Hence, is there any possible linkage between them? In addition to a thorough case description, the literature concerning this entity is reviewed and discussed.