An unusual mechanism of metastasis in serous carcinoma of the endometrium associated with BRCA1 mutation gene: A case report with clinical and immunohistochemical features

The current case report documented a uterine highgrade serous carcinoma in a 48yearold woman with previous clinical history of breast cancer, BRCA1 gene mutation, and melanoma of the back. Uterine Serous Carcinoma (USC) was minimally invasive with fallopian tubes, ovaries, omentum, peritoneal surface and lymph node biopsy demonstrating no evidence of neoplasm at the time of total abdominal hysterectomy with bilateral salpingooophorectomy. In the peritoneal washing cytology and in the lumen of both fallopian tubes there were neoplastic cells which, on immunohistochemical analysis, showed immunoreactivity for p53 and p16 and negativity for WT1, supporting the endometrial origin of these malignant serous neoplastic cells. One year after surgery, the patient presented with recurrent peritoneal neoplastic nodules and metastases into intestinal lymphnodes. To detect neoplastic USC cells in the fallopian tube lumen and to prove a retrograde transtubal spread into the peritoneal cavity, it is mandatory to examine the fallopian tubes in their entirety according to the SEEFIM (Sectioning and Extensively Examining the Fimbria) protocol. In addition, this case report highlights the importance of the peritoneal cytology and omentectomy during a total abdominal hysterectomy with bilateral salpingooophorectomy to establish adequate staging and future patient management, even in cases of minimally invasive serous endometrial carcinoma.