[Wolffian adnexal tumors (FATWO)].

Tumors originating from the remnants of the mesonephral (Wolf's) duct, known as FATWO (Female Adnexal Tumor of Probable Wolffian Origin), belong to the category of rare neoplasms of the female reproductive system. The tumor was first described in 1973 by doctors Kariminijad and Scully from the University of Texas M.D. Anderson Cancer Center. Since then, about 100 cases of FATWO have been recorded worldwide. The localization of the tumor is associated with the threefold laying of the Wolf duct in embryogenesis: from the ovarian gate, along the mesosalpinx, in the wide ligament of the uterus along its lateral wall to the outer third of the vagina. This publication presents the case of a 57-year-old patient whose abdominal ultrasound revealed a bulky tumor of the right ovary. During intraoperative revision of the abdominal cavity and pelvic cavity, tumor masses were also found on the parietal peritoneum, mesentery of the sigmoid colon, in the large omentum, and fatty tissue of the anterior abdominal wall. A radical surgical intervention was performed with the removal of all metastatic foci. Upon histological examination, the structure and cytological signs of the formation were not characteristic of a tumor with a high degree of malignancy. Taking into account the results of the immunohistochemical study and the data of the clinical course, the diagnosis of FATWO was made. The rarity of this nosological form and its genetic heterogeneity create difficulties in the pathohistological diagnosis of neoplasms due to the presence of only relatively specific immunohistochemical markers, which make it possible to exclude more common tumors with a similar morphological pattern.