CD5-positive diffuse large B-cell lymphoma of the uterus: a Case Report with cytologic findings from uterine cavity drainage and literature review

Objective: Cases of diffuse large B-cell lymphoma (DLBCL) of the uterus co-expressing CD5 are exceedingly rare and diagnostically challenging due to its nonspecific clinical and radiological features, which often mimic other uterine malignancies. This study retrospectively analyzes the cytopathological and histopathological characteristics of this entity in uterine cavity drainage fluid to facilitate its recognition. Methods: We analyzed a case of uterine CD5-positive DLBCL by collecting clinical data, imaging findings, cytology from uterine drainage fluid, and histology from endometrial curettage. A review of the pertinent literature on uterine DLBCL was also performed. Results: hybridization for Epstein-Barr virus-encoded small RNA (EBER) was negative. The Ki-67 proliferation index was 90%. These findings supported a diagnosis of CD5-positive DLBCL, non-germinal center B-cell subtype. Conclusion: Uterus DLBCL expressing CD5 is an exceedingly rare malignancy. Its diagnosis necessitates a comprehensive approach integrating clinical presentation, imaging, cytomorphology, and immunohistochemistry. Increased awareness of the cytological features of lymphoma in uterine drainage fluid is essential to prevent diagnostic oversight.