Displaced Granulosa Cells in the Fallopian Tube Mistaken for Metastatic Granulosa Cell Tumor

Abstract

A 44-yr-old woman underwent a total hysterectomy and bilateral salpingectomy secondary to uterine leiomyomas. Gross examination of the fallopian tubes revealed no masses or lesions; however, 2 small foci of granulosa cells were identified microscopically within one of the fallopian tubes. These foci were suspicious for granulosa cell tumor metastases. The patient subsequently underwent a bilateral oophorectomy, which revealed no primary granulosa cell tumor. Immunohistochemical studies were used to help support the benign nature of the granulosa cells within the fallopian tube. A review of the literature revealed only 1 similar case report of displaced benign granulosa cells within the fallopian tubes. The ovaries in both this case and the previous case report were found to contain multiple cystic follicles, suggesting ovulation as the likely mechanism of displacement. Knowledge of this rare occurrence and the use of immunohistochemical staining are paramount to making a correct diagnosis, thus preventing a misdiagnosis of malignancy and possible unnecessary treatment.

Microscopic extraovarian sex cord proliferations: an undescribed phenomenon

“…Normal granulosa cells may be mitotically active, and this may further heighten the suspicion of malignancy. This displacement of granulosa cells is most likely to be an artefact of surgery or specimen dissection, although it could also be secondary to ovulation . The sex cord proliferations reported here differ from such displaced granulosa cells in that the nuclei in the former are usually vesicular rather than hyperchromatic and do not have a crushed appearance.…”

“…This displacement of granulosa cells is most likely to be an artefact of surgery or specimen dissection, although it could also be secondary to ovulation. [19][20][21][22] The sex cord proliferations reported here differ from such displaced granulosa cells in that the nuclei in the former are usually vesicular rather than hyperchromatic and do not have a crushed appearance. Moreover, displaced granulosa cells do not show the various architectural arrangements seen in some of our cases.…”

“…One of us (W Glenn McCluggage) has seen several cases of displaced granulosa cells within the fallopian tube (W Glenn McCluggage, unpublished observations), and this may be a diagnostic consideration, especially with tubal sex cord proliferations. A recent report has described a similar case of displaced granulosa cells within the fallopian tube, but we feel, on review of the photomicrographs, that this may represent a sex cord proliferation similar to the cases reported here rather than displaced granulosa cells; in particular, it bears a close morphological resemblance to case 6 in our series.…”

“…One differential diagnosis of the lesions described here that is worthy of consideration is the phenomenon whereby granulosa cells are displaced from developing ovarian follicles into ovarian tissue spaces and true vascular spaces and also occasionally into extraovarian tissues, including the fallopian tube. [19][20][21][22] These displaced granulosa cells typically have hyperchromatic nuclei, which are often crushed and show moulding, and potentially mimic small-cell carcinoma (Figure 7). When the granulosa cells are luteinized, the displaced cells may simulate non-small-cell carcinoma or other neoplasms.…”

Displaced Granulosa Cells Within the Ovarian Stroma in a BRCA1 Mutation Carrier

“…We have read with interest the recent paper by Duncan et al (1) describing benign clusters of granulosa cells within the fallopian tube of a total hysterectomy with bilateral salpingectomy specimen. Indeed, the pathologist should be aware of the range of benign mimickers, particularly when examining prophylactic salpingo-oophorectomy specimens.…”