Malignant Mixed Müllerian Tumor with an Extensive Squamous-Cell Carcinomatous Component: A Potential Pitfall in Liquid-Based Cervical Cytology

Abstract

Background: Malignant mixed Müllerian tumors (MMMTs) are aggressive tumors arising in the female lower genital tract and characterized by the presence of both a malignant epithelial and a mesenchymal component. Here, we report a case of an MMMT of the uterine corpus with an extensive squamous-cell carcinomatous component processed by liquid-based cytology (LBC). Case Report: An 84-year-old woman with a prior history of anal squamous-cell carcinoma, who complained of vaginal bleeding, was discovered to have a mass protruding from the uterine cervix. A Papanicolaou (Pap) test was performed and the LBC (ThinPrep) preparation showed a background of neutrophils and cellular debris. Atypical cells were identified that presented with hyperchromatic nuclei, nuclear membrane irregularities, multinucleation and abundant cytoplasm with focal keratinization. Scattered nucleolated malignant elements were also identified. The cytological diagnosis resulted in ‘suspicious for squamous-cell carcinoma', favoring primary cervical carcinoma rather than extracervical (anal) carcinoma. The histological examination showed that it was an MMMT with an extensive squamous-cell carcinomatous component. Conclusion: This case illustrates the potential diagnostic pitfall of MMMTs with extensive squamous-cell carcinomatous components in LBC Pap smears. Cytopathologists should keep in mind this diagnostic possibility in postmenopausal women who experience vaginal bleeding or spotting.

Cytological features of uterine tumors resembling ovarian sex‐cord tumors in liquid‐based cervical cytology: a potential pitfall. Report of a unique and rare case

“…However, retrospectively, large sheets of glandular cells or crowded groups of tumor cells with feathery edges were not present. Clinical presentation with a necrotic mass protruding in the vaginal cavity raises the possibility of a diagnosis of MMMT . In fact, the sarcomatous component does not easily shed, and Pap tests may only show the malignant epithelial component .…”

A rare and challenging case of uterine mass successfully reported in a cervical smear

“…Our cytological features overlapped with previously described reports, [ 4 - 6 ] indicating that carcinosarcoma should always be considered in cases where malignant epithelial and spindly cells are found on a dirty background, especially in women presenting with postmenopausal bleeding. [ 7 ] In contrary, other studies have indicated that sarcomatous components are rare findings in cytological smears which make diagnosis of carcinosarcoma difficult. [ 6 , 8 ] A study by Hanley et al .…”