Primary Ovarian Mucinous Cystic Tumor With Prominent Theca Cell Proliferation and Focal Granulosa Cell Tumor in its Stroma: Case Report, Literature Review, and Comparison With Sertoli-Leydig Cell Tumor With Heterologous Elements

Abstract

A 73-year-old woman was found to have a 22 cm unilateral multilocular mucinous cystic tumor of the ovary. Microscopic examination showed a routine appearance of the epithelial component, which ranged from benign to borderline to low-grade carcinoma. The stromal component was unusual because of a striking cellular theca cell component in the stroma, which, in turn, merged with a component of adult granulosa cell tumor. The "parent" neoplasm in this case and 3 other similar cases in the literature appears to be the mucinous neoplasm, in contrast with the other example of mucinous neoplasia associated with sex cord neoplasia, the Sertoli-Leydig cell tumor with heterologous elements, in which the "parent" neoplasm is likely the Sertoli-Leydig cell tumor.

Mucinous Cystadenoma Coexisting With Adult Granulosa Cell Tumor in the Ovary

“…However, the 2 of them occurring simultaneously in the same ovary is extremely rare with only 5 cases reported in the literature (3)(4)(5)(6)(7). Two additional cases cited earlier in the literature probably do not qualify to be included in this group, as one of them (8) also had a mature cystic teratoma in the same ovary whereas in the other case (9) the mucinous component was malignant.…”

“…Such a phenomenon would not be entirely unexpected, as both AGCT and SLCT are sex cord-stromal tumors and granulosa cell tumors and have shown heterologous hepatocyte differentiation (11). The granulosa cell component in our case, as in 4 other cases (3,(5)(6)(7), was intimately admixed with the mucinous component occurring in the walls of the mucinous cyst and in solid nodules as well. The heterologous mucinous component seen in SLCTs is of the intestinal type (10).…”

“…Therefore, the second possibility does not explain this case. The third hypothesis of AGCT arising from the reactive theca cell proliferation that may be seen in the wall of a primary mucinous cystadenoma as proposed in the recently published case report by Staats et al (7) was already propounded by Kushida et al (5) in 2005. We believe that if this was true, then there should have been more cases of such combination than the few that have been reported, as it is not uncommon to see a luteinized functioning stroma adjacent to the mucinous epithelium in mucinous cystadenomas.…”

“…In our case as well, the epithelium showed goblet cells and it was diffusely strongly positive for CK20. The mucinous cysts being large and the granulosa cell component being small in some cases have been used as an argument against the heterologous element theory by Staats et al (7), as the heterologous mucinous cysts in SLCTs are usually small. However, it is well accepted that demonstration of a small Sertoli-Leydig cell component in an otherwise mucinous cystadenoma would favor the diagnosis of SLCT with heterologous elements.…”

“…The simultaneous occurrence of mucinous cystadenoma and adult granulosa cell tumor (AGCT) in the same ovary is extremely rare with only 5 cases reported in the literature (3)(4)(5)(6)(7). Histogenesis of these tumors has been a matter of debate and remains inconclusive.…”