main results and the role of chance: A total of 1128 adnexal masses were resected, and 13 patients (1.5%) had ovarian malignancies: 6 ovarian cancer (1 mucinous, 1 endometrioid G1, 1 granulosa cell and 3 carcinoid) and 7 borderline tumors (BOTs; 5 mucinous and 2 serous). Of these, two patients with mucinous BOTs underwent fertility-sparing surgery and six patients underwent staging laparotomy. Due to cyst rupture during surgery, nine patients (69.2%) were upgraded to tumor stage IC. Secondary surgeries were performed in eight patients, with a mean interval of 88.9 days (range, 39 -182 days) between the surgeries. All patients were alive and without evidence of disease at follow-up (mean follow-up, 38 months; range, 6 -80 months).limitations, reasons for caution: This was a retrospective study with a small case number and a short follow-up period. wider implications of the findings: The presence of an early-stage unexpected ovarian malignancy did not alter the patient's prognosis, even if there was a significant delay in surgical staging after the finding of an unexpected malignancy during laparoscopy.