This patient, who has early-stage ovarian cancer (clinical stage II, with spread beyond the ovaries but confined to the pelvis), should undergo exploratory surgery. The diagnosis of ovarian cancer is usually made by surgical exploration, as there is survival benefit following intact removal of an adnexal mass in patients with early-stage disease. Survival is also improved when surgery is performed by a specialized gynecologic oncologic surgeon. If ovarian cancer is confirmed at surgery, appropriate procedures include peritoneal washings for cytology, total abdominal hysterectomy and bilateral salpingo-oophorectomy, omentectomy, full abdominal and pelvic exploration with biopsy of any masses suspicious for cancer, lymph node evaluation, and, for patients with advanced ovarian cancer, debulking of the tumor by removing as much of the cancer as possible. Optimal tumor debulking (leaving residual masses that are each less than 1 cm) improves survival.

CT-guided or ultrasound-guided biopsy of a suspected ovarian mass is contraindicated, as this may cause rupture and dissemination of cancer cells. Rupture of an ovarian mass increases the risk of peritoneal recurrence; when such rupture occurs during surgery, it is an indication for adjuvant chemotherapy, even in early stage disease.

MRI of the abdomen and pelvis is sometimes used in the preoperative staging of ovarian cancer as an alternative to CT but is unlikely to yield additional information after CT scans and ultrasound examinations are done.

Based on National Comprehensive Cancer Network guidelines, all women with ovarian cancer are eligible for BRCA1/2 testing. Ten percent to 15% of ovarian cancers are hereditary, with BRCA1/2 mutations being the most common. Although the initial surgical and standard adjuvant chemotherapy treatments for ovarian cancer are the same regardless of the presence of a hereditary mutation, patients with BRCA1/2 mutations are at risk for other cancers, particularly breast cancer, and additional screening and prophylaxis options would be discussed once treatment for ovarian cancer is complete. In addition, patients with BRCA1 mutations are eligible for clinical trials of agents that are particularly effective in BRCA1-related recurrent ovarian cancers, such as PARP inhibitors. However, it is not yet known whether this patient has ovarian cancer, and testing before this diagnosis is established is inappropriate.