What happened, in summary

A woman in her mid-30s developed abdominal pain and bloating over 3 weeks, followed by fever, nausea, urinary symptoms, and rapidly worsening kidney function. Imaging found a large pelvic mass, and the kidney injury did not improve with standard measures. With ovarian cancer strongly suspected and her condition deteriorating, a multidisciplinary team performed emergency cytoreductive surgery. The operation included ureteric stents, drainage of ascites, hysterectomy, removal of both ovaries and fallopian tubes, omentectomy, para-aortic lymph-node dissection, and excision of bladder peritoneum. No visible tumor remained.

Pathology showed stage IIIC small cell carcinoma of the ovary, hypercalcaemic type, involving the left ovary, left fallopian tube, and 11 of 18 para-aortic lymph nodes. Tumor testing found somatic SMARCA4 alterations but no germline SMARCA4 pathogenic variant. Kidney function improved within hours of surgery, supporting a cancer-related paraneoplastic cause.

She began carboplatin and etoposide, with bleomycin added for 3 cycles. Disease progressed after 6 first-line cycles. She then received 30 Gy of radiation in 10 fractions with pembrolizumab, carboplatin, and paclitaxel. A mixed response led to a second 30 Gy course in 10 fractions. Treatment continued, and imaging after 13 cycles showed an excellent response.