Cytological diagnosis of hyaline-vascular type of Castleman disease.

Castleman disease (CD) is a rare, benign lymphoproliferative disorder, mostly involving the mediastinal lymph nodes, but can occur wherever lymphoid tissue is found. With only a few published case reports, there needs to be more literature on its cytological findings. We report the case of a 63-year-old female presenting with left upper cervical swelling. Fine needle aspiration cytology smears showed variably sized lymphoid follicles with diminished germinal centers, prominence of follicular dendritic cells, and capillaries traversing some of the follicles. The possibility of a hyaline-vascular type of Castleman disease was suggested. Histopathology confirmed the cytological diagnosis. The index case is being presented to discuss the cytological features of the CD along with its histological and immunohistochemical correlation.