Small-cell carcinoma of the ovary, hypercalcemic type (SCCOHT) is an extremely rare and aggressive ovarian malignancy associated with SMARCA4 mutation, accounting for less than 0.01% of ovarian tumors. It predominantly affects young females and is characterized by poor prognosis. Here, we report a unique case of SCCOHT with a special pathological classification of large cell variant type in a 59-year-old postmenopausal woman, an age that is rare for this disease.
A 59-year-old female patient presented with lower abdominal pain. A hard and restricted mass was palpated at the back of the uterus during pelvic physical examination. MRI examination showed a huge solid mixed-signal mass shadow in the right adnexal area, with a size of 10 × 7 × 7 cm.
Postoperative histopathological and immunohistochemical analyses demonstrated abundant large cells under microscopic examination and a loss of BRG1 protein expression, leading to the diagnosis of large cell variant of SCCOHT in right ovary. Genetic testing confirmed a mutation in the SMARCA4 gene (exon 6, c.1103del p.[Q368Rfs*43]).
The patient underwent pelvic tumor cytoreductive surgery and pelvic adhesion release surgery, and the implanted lesions in the pelvic cavity were resected during the operation.
The patient underwent extensive surgical resection and completed 6 cycles of TC chemotherapy (paclitaxel + carboplatin). Despite the postoperative pathological stage reached Stage II, during the 18-month follow-up after the operation, no evidence of tumor progression or recurrence was observed.
SCCOHT is a highly malignant tumor associated with a generally poor prognosis, particularly for tumors at stage II or higher. Nevertheless, the favorable prognosis observed in this case suggests that the traditional understanding may require reevaluation. Whether there is a correlation between the age of onset of SCCOHT and the prognosis remains to be elucidated through systematic clinical research in the future.