Bilateral lymph node metastases from primary uterine carcinosarcoma : an immunohistochemical case study

Uterine carcinosarcomas (UCs) are extremely rare but highly malignant neoplasms originating in female genital tract. The 5-year survival of advanced-stage UCs is not satisfactory yet, being below 10%. They metastasize to different organs, most frequently to the lungs (49%), peritoneum (44%), as well as to the pelvic and para-aortic lymph nodes (35%). Herein, we report a case of a 64-year-old woman with a primary UC metastasizing bilaterally to the pelvic lymph nodes. We applied a panel of immunohistochemical markers to assess the staining pattern of the primary tumor and corresponding metastases. In this assessment, the carcinoma component of the UC and lymph node metastases showed similar staining patterns, except for EP4 and p53, being positive in primary tumor and right side metastases. On the other hand, sarcoma component and lymph node metastases showed differences in some of the markers applied. MIB-1 proliferative activity was slightly higher in bilateral pelvic lymph node metastases compared to UC components. Our case report supports the concept of the epithelial component being the driving force for female genital tract UCs as our patient presented a similar staining pattern of carcinomatous component-lymph node metastases in selected markers.