Malignant mixed müllerian tumor with a lung metastasis: Fine needle aspiration cytology and histology correlation

ABSTRACT: Malignant mixed müllerian tumors (MMMTs), better referred to as carcinosarcomas, are rare but highly aggressive tumors. They are histologically characterized by a biphasic pattern, having both a malignant epithelial (carcinomatous) and a malignant stromal (sarcomatous) component. Malignant mixed müllerian tumors usually affect postmenopausal women and most commonly arise from the uterus. Patients often present at an advanced stage of disease and have poor clinical outcomes. Fine needle aspiration (FNA) cytology of these tumors has rarely been reported in the literature. We herein report a uterine MMMT that metastasized to the lung in a 36-year-old woman. Cytologic analysis of the lung mass sampled by means of FNA revealed components of both endometrioid adenocarcinoma and sarcoma, features similar to the histologic findings of her primary tumor. We review the literature and discuss potential pitfalls that can affect the cytologic diagnosis of metastatic MMMTs on FNA samples.