Pelvic Inflammatory Disease Mimicking Ovarian Cancer: A Case Series from A Tertiary Cancer Center

The female pelvis has a complex anatomy, and benign adnexal diseases can present as malignant ovarian masses clinically and radiologically. Between 1 June 2011 and 28 September 2022, we included in this study all the patients who were diagnosed initially with suspicious ovarian masses in the Department of Surgical Oncology, Oncology Center, Mansoura University, Egypt, and after surgical exploration revealed pelvic inflammatory disease and we assessed their diagnostic, operative, and postoperative outcomes. In this case series we had 41 patients of a total of 803 cases with suspicious adnexal mass that revealed pelvic inflammatory disease after surgical exploration, abdominal pain was the common presentation in 53.7% of the cases, and low-grade fever was reported in seven cases. The serum cancer antigen 125 was elevated in 70.7% of the cases. Unilateral adnexal mass was found in 30 cases and 11 cases had bilateral adnexal masses. We followed up on the patients within 47 months (range 12–88 months); recurrent pelvic inflammatory disease has developed in one case after 62 months and ovarian cancer has developed in another case after 80 months. We concluded that benign adnexal masses such as tubo-ovarian abscess secondary to pelvic inflammatory disease should be considered a differential diagnosis in patients with radiological suspicious adnexal masses when the tumor markers such as cancer antigen 125 are normal or mildly elevated, especially in premenopausal women, and the clinical presentations are not specific to either benign or malignant adnexal diseases.