Vascular embolization of benign granulosa cells

Incidental Microscopic Granulosa Cell Proliferations: Tumorlet or Non-neoplastic?

Microscopic granulosa cell proliferations are rare incidental findings in ovarian and extraovarian tissue, and can simulate granulosa cell tumors. We report a case of a 22-yr-old nulliparous woman with incidental microscopic granulosa cell proliferation in the wall of an endometriotic cyst. Excision of the cyst revealed extensive endometriosis and incidental microscopic nests and cords of granulosa cells measuring 1.5 mm and positive for inhibin A and calretinin. A rare Call-Exner body was noted. An extensive literature review of both ovarian and extraovarian granulosa cell proliferations were performed to determine their possible origin, variable morphologic features and differential diagnosis. Forty-seven cases were identified occurring in pregnant (26%) and nonpregnant (74%) settings. The nonpregnant cases reveal an association with endometriosis and endometrioid adenocarcinomas. Follow-up data is very limited, but no reports of subsequent granulosa cell tumors are reported. We hypothesize that possible anovulation may play a role in the development of these proliferations. Because of unknown pathogenesis and limited follow-up data being available, their clinical significance and risk of neoplasia remain unclear.

Generation of multi-oocyte follicles in the peripubertal rat ovary: link to the invasive capacity of granulosa cells?

OBJECTIVE

To assess the presence and numbers of multi-oocyte follicles (MOFs) in the rat ovary at different stages of postnatal maturation.

DESIGN

Animal (rat) study.

SETTING

Research laboratory.

ANIMAL(S)

Female Wistar rats.

INTERVENTION(S)

Histologic/morphometric analyses in ovaries from infantile, juvenile, pubertal, and adult female rats.

MAIN OUTCOME MEASURE(S)

Numbers and characteristics of MOFs in rat ovaries at different stages of postnatal maturation.

RESULT(S)

Female rats displayed low numbers (<5/ovary) of MOFs in the infantile period (postnatal day [PND] 15). The occurrence of MOFs increased sharply by PND-21 and remained at high values (>15/ovary) up to PND-60, to decline thereafter by PND-90. The presence of irregularly shaped and connected adjacent follicles, together with the identification of ruptures at the follicle surface and the occasional invasion of the ovarian stroma by granulosa cells, strongly suggests that the majority of MOFs in peripubertal rats are generated by fusion of adjacent growing follicles.

CONCLUSION(S)

A new mechanism for the generation of MOFs linked to the potential invasive capacity of granulosa cells is proposed. The basis for the upsurge in the generation of MOFs during the peripubertal period and whether, as predictable, this phenomenon is applicable to other mammalian species warrant further investigation.

Granulosa cells in the uterosacral ligament: case report and review of the literature

Granulosa cells are components of the sex cord-stromal cells in the ovary responsible for steroidogenesis. Uncommonly, extraovarian granulosa cells have been reported to be associated with malignant processes of the ovary. We report a unique case of benign granulosa cells, found during routine laparoscopic evaluation, in the uterosacral ligaments in a 20-year-old patient with chronic pelvic pain and infertility. Possible mechanisms include implantation of released granulosa cells from a normal ovary or arising from a focus of müllerianosis. Of note, a focus of endosalpingiosis and endometriosis was also identified within the specimen.

Non-neoplastic granulosa cells within ovarian vascular channels: a rare potential diagnostic pitfall

AIMS

To describe six cases seen in consultation in which artefactual vascular involvement within the ovary by benign granulosa cells caused diagnostic confusion.

METHODS/RESULTS

In five cases, the initial favoured diagnoses of the submitting pathologists were metastatic carcinoma (three cases) and immature neural elements within a teratoma (two cases). In two cases, the ovary contained a benign cystic teratoma (one with struma ovarii), in two cases endometriosis, in one case follicular cysts, and in the other no pathological lesion was present. In all cases, several small ovarian vascular channels contained cohesive groups of cells with mildly atypical nuclei and cytoplasm, which varied from scant to abundant and eosinophilic. In four cases, mitotic figures were identified. The cells were morphologically consistent with benign granulosa cells and were associated in four cases with a nearby follicle lined by similar cells. There was no evidence of a mass lesion, grossly or histologically, to suggest a granulosa cell tumour. The nature of the cells was confirmed using immunohistochemistry for alpha inhibin and calretinin in one case.

CONCLUSIONS

This phenomenon is probably an artefact secondary to surgical trauma or sectioning within the laboratory; alternatively, it could be related to ovulation. It is important that this benign process is not misinterpreted as cancer, either primary or metastatic, which may prompt inappropriate treatment or investigations that are not needed.