B. High-grade serous carcinoma of gynecological origin
This patient underwent left axillary excisional lymph node biopsy, peritoneal washings, laparoscopic bilateral salpingo-oophorectomy, omental biopsy, and bilateral ureterolysis. Laparoscopy revealed that both ovaries were affixed to the pelvic peritoneum with adhesions, requiring bilateral ureterolysis. The uterus, cervix, and proximal fallopian tubes were surgically absent. On gross examination the distal fallopian tubes appeared unremarkable, and the left ovary appeared nodular. Given the clinical scenario, the fimbrial ends of the fallopian tubes were entirely excised and submitted for microscopic examination along with both ovaries. Microscopic examination revealed a residual 2.1-mm focus of high-grade serous carcinoma (Figure 2) involving the fimbrial end of the left fallopian tube. No omental involvement was seen. The immunostaining pattern was similar to that seen in the axillary metastasis prior to therapy. No residual carcinoma was identified in the left axillary lymph node. The patient’s cancer antigen 125 level was 13 U/mL before the surgery. Disease was staged as FIGO (International Federation of Gynecology and Obstetrics) stage IVB, and the patient received additional platinum-based adjuvant chemotherapy. Test results were negative for germline pathogenic sequence variants, including BRCA1 and BRCA2.