Difficulties in the differential diagnosis of tumors in the female reproductive system

Introduction. Most pelvic tumors originate from reproductive organs. Even using the up-to-date imaging techniques, radiologists experience difficulties in determining the source of the lesion since a wide range of tumors look similar to each other on the distorted backdrop of pelvic anatomy, large invasive formations, and an active inflammatory reaction of the pelvic peritoneum. Aim: to evaluate “pitfalls” in the preoperative noninvasive diagnosis of female pelvic tumors by applying the clinical diagnostic tools. Materials and methods. Four rare clinical cases were analyzed; all of them posed difficulties in interpreting the diagnostic examination due to their atypical characteristics. There were 2 cases of ovarian cancer, initially identified by an experienced team of radiologists as benign pelvic pathology. Also, there were fibroids with degeneration, marked proliferative activity, and a massive inflammatory reaction of the peritoneum – that was diagnosed as a malignant ovarian tumor. Tumor biopsies were examined using morphological and immunohistochemical methods (with the р16, Ki-67, p53, CD 117, S 100, CD 34 markers). Immunohistochemical (IHC) studies were performed with formalin-fixed paraffin materials using the avidin-biotin-peroxidase method. Antibodies to estrogen receptor (ER), progesterone receptor (PR), cytokeratin 7 (CK7), cytokeratin 20 (CK20) and Wilms tumor protein 1 (WT1) were also used. Results. A thorough analysis of the clinical picture and a joint multidisciplinary discussion (gynecologist, oncologist, radiologist, etc.) made it possible to avoid diagnostic errors. Conclusion. These observations demonstrate the difficulties of differential diagnosis between ovarian metastases of uterine cancer and primary multiple ovarian and uterine cancer, as well between leiomyosarcoma and uterine myoma with high mitotic activity. Obviously, the change in diagnosis calls for a change in the treatment strategy.