- Extraovarian pelvic yolk sac tumors are rare, with only nine cases documented previously in the published work. We report a case of extraovarian pelvic yolk sac tumor occurring synchronously with breast carcinoma. The patient underwent resection of the pelvic tumor and hepatic implant, omentectomy and breast lumpectomy with sentinel axillary lymph node biopsy. The uterus and bilateral adnexa were preserved. Postoperative adjuvant therapy for the yolk sac tumor included three cycles of the bleomycin, etoposide and cisplatin (BEP) regimen. This was followed by adjuvant chemotherapy and radiotherapy for the breast carcinoma. It is concluded that in women with extraovarian pelvic yolk sac tumor who wish to preserve childbearing capacity, fertility-saving surgery followed by fertility-preserving cisplatin-based chemotherapy is adequate and appropriate treatment.