Effusion cytology of metastatic carcinosarcoma

OBJECTIVES: Carcinosarcomas (CSs) are rare gynecological neoplasms seen in elderly females. These are composed of malignant epithelial and mesenchymal components, which appear as adenocarcinoma and high-grade sarcoma. Effusions are encountered uncommonly in CS. MATERIAL AND METHODS: The study focuses on the cytomorphology of 10 cases of metastatic CS in effusions. In 6 years, there were 10 (0.45%) cases of metastatic CS in effusion samples out of 2240 malignant effusion samples. The samples were processed by SurePath(™) and centrifuge technique. Both May–Grünwald–Giemsa and Papanicolaou stained smears were evaluated for cytomorphological features, and the findings were correlated with subsequent histopathology. RESULTS: The cells were predominantly arranged in ball-like clusters and discretely. The cells had abundant vacuolated cytoplasm and enlarged pleomorphic nuclei. Occasional cases showed scattered spindle cells. The cases were diagnosed as metastatic adenocarcinoma (7/10) and positive for malignant cells (3/10). None of the cases was diagnosed as CS. The primary of these cases was in the uterus (7/10) and ovary (3/10). CONCLUSION: The cytological evaluation of such effusion samples rarely demonstrates the classical biphasic pattern of these tumors. Mostly, the carcinomatous component is evident, and the sarcomatous element is inapparent and readily missed.