Adult-type granulosa cell tumor, presenting as extraovarian metastases: ultrastructural diagnosis

All granulosa cell tumors have the potential to recur locally or metastasize, in spite of apparent complete surgical excision. Long-term follow-up is particularly important in these tumors, since recurrences may occur many years after the initial diagnosis. This report highlights the ultrastructural findings that led to the diagnosis of metastatic granulosa cell tumor in two patients presenting with extraovarian masses. In patient 1 the information about an ovarian granulosa cell tumor removed 9 years before the current admission was obtained only after the metastatic tumor was correctly diagnosed. In patient 2 the ovarian primary was found after abdominal wall involvement by granulosa cell tumor was diagnosed. Thus, in both cases the clinical circumstances were atypical and electron microscopic examination of the tumors was essential to make the diagnosis of granulosa cell tumor with confidence. Based on the features observed in these two extraovarian tumors as well as eight other primary ovarian granulosa cell tumors from our files, a consistent ultrastructural profile is identified that can be very useful for diagnosis.