SMARCA4 Deficient Tumours of Ovary and Uterus: 2 Case Reports with Review of Literature

Swi/Snf Related,Matrix Associated, Actin Dependent Regulator Of Chromatin,Subfamily A,Member 4 (SMARCA4-deficient) tumors are typically aggressive, characterized by undifferentiated round cells or rhabdoid features histopathologically. These tumors are rarer compared to their other epithelial counterparts and generally have a poorer prognosis. Here, we report two cases with mutations in the SMARCA4 gene. The first case involves a 29-year-old woman with Small Cell Carcinoma of the Ovary Hypercalcemic Type (SCCOHT). She presented with lower abdominal pain, and Contrast Enhanced Compututed Tomography (CECT) imaging indicated widespread abdominopelvic disease with left supraclavicular and axillary lymph nodes. A biopsy revealed undifferentiated carcinoma with loss of Brahma-Related Gene-1 (BRG-1) and retention of Integrase Interactor-1 (INI-1) on Immunohistochemistry (IHC). Despite receiving three cycles of etoposide/carboplatin and seven cycles of a four-drug regimen (cisplatin/adriamycin/ etoposide/cyclophosphamide), she succumbed to the disease while on supportive care, with an overall survival of 13 months. The second case involves a 38-years-old woman with SMARCA4-Deficient Uterine Sarcoma (SDUS). She presented with lower abdominal pain, an enlarged uterus, thickened endometrium, and bilateral ovarian and nodal deposits. An omental biopsy revealed large tumor cells with vesicular nuclei, and IHC suggested diffuse expression of Cluster Of Differentiation 99 (CD99), with similar BRG-1 loss and INI-1 retention. She received two lines of chemotherapy (gemcitabine/docetaxel and adriamycin/ifosfamide) but unfortunately succumbed to the disease within four months of diagnosis. Both patients presented at advanced stages and were only able to receive conventional chemotherapy due to financial constraints. Newer promising therapies need to be explored in such rare cases, where treatment protocols are still under evaluation for standard of care and efficacy, wherever resources permit. Keywords: Rare cancers, Smarca 4 Deficient Uterine Sarcoma (SDUS), Small Cell Carcinoma of the Ovary Hypercalcemic Type (SCCOHT), (Swi/Snf Related,Matrix Associated, Actin Dependent Regulator Of Chromatin, Subfamily A, Member 4 ) SMARCA4 deficient.