Different clinocopathological presentations of steroid cell tumour - Report of three rare cases.

INTRODUCTION AND IMPORTANCE: We present three cases of steroid cell tumour due to their rarity, their differing clinical presentations and the distinct pathology. CASE PRESENTATION: Case 1: A 50-year-old female presented with heavy menstrual bleeding. Adenomyosis and multiple leiomyomata were found along with an incidental 2.5mm, paratubal steroid cell tumour. Given the size of the tumour and the histopathological features this was considered benign. Case 2: A 69-year-old female patient presented with virilization, found to have a left ovarian steroid cell tumour. Since there was capsular infiltration, close follow up was advised. Case 3: A 35-year-old female patient presenting with an acute abdomen due to torsion of a 15 cm right ovarian mass. The mass showed immunomorphological features of a steroid cell tumour. Since this tumour was large and had features of necrosis, high mitotic activity and nuclear pleomorphism, it was regarded as malignant. CLINICAL DISCUSSION: Steroid cell tumours of the ovary are rare (<0.1 % of all ovarian neoplasms) with uncertain malignant behaviour and are difficult to diagnose especially if classical virilising symptoms are absent. CONCLUSION: Thorough histopathological analysis and immunohistochemistry are essential in arriving at a definite diagnosis when the classical presentation is absent.

Unusual Aspects of Small Cell Carcinoma of the Ovary of Hypercalcaemic Type: Retained SMARCA4 Immunohistochemical Staining and Positive Staining With TLE1.

Small cell carcinoma of the ovary of hypercalcaemic type (SCCOHT) is a rare and aggressive ovarian neoplasm that is most common in the second and third decades. Molecular studies have established inactivating SMARCA4 alterations as the driver of SCCOHT, these being present in over 95% of these neoplasms. SMARCA4 alterations almost always result in loss of immunoreactivity with SMARCA4 (BRG1) antibody, and this is an extremely useful adjunct in the diagnosis of SCCOHT. Herein, we report 7 cases of SCCOHT (2 from the same patient) with retention of nuclear immunoreactivity with SMARCA4, but with SMARCA4 alterations identified on molecular testing. All cases exhibited loss of SMARCA2 (BRM) immunoreactivity. In addition, following the identification of diffuse TLE1 immunoreactivity in one of these cases (which did not exhibit an SS18 gene rearrangement characteristic of synovial sarcoma), we stained a total of 63 cases of SCCOHT (14 on whole tissue sections: 49 on tissue microarray) with this marker and 7 of 14 (50%) and 22 of 49 (45%) were positive on whole sections and tissue microarray, respectively. Most cases were focally positive but occasional cases exhibited diffuse immunoreactivity. Our observations highlight the importance of SMARCA2 immunohistochemical staining and molecular testing in suspected cases of SCCOHT that exhibit retained SMARCA4 immunoreactivity. Th common expression of TLE1 in these neoplasms represents a potential diagnostic pitfall since synovial sarcoma may be considered in the differential, especially in cases with retained SMARCA4 immunohistochemistry.