Fig. 1Overall histopathologic and cytopathologic findings in excision of inguinal lymph node, needle biopsy of mediastinal lymph node, and aspiration cytology by liquid-based preparation (LBP) of mediastinal lymph nodes. (A) Epithelioid tumor cells are arranged in a solid sheet and nest with focal vascular channel formation. (B) The major tumor cells are large and epithelioid with round nuclei, prominent nucleoli and sparse to plump cytoplasm. (C) Tumor cells are positive for CD31. (D) A few loose clusters or microacini with a central lumen are identified. (E) Tumor cells are positive for CD31. (F) Vague microacini formation is also identified in aspiration cytology by LBP (Papanicolaou stain).
Fig. 2Variable cytoplasmic features in needle biopsy of mediastinal lymph nodes and aspiration cytology by liquid-based preparation of mediastinal lymph nodes. Needle biopsy demonstrates intracytoplasmic vacuoles (A), perinuclear clearing (E), and juxtanuclear condensation (I). These histopathologic findings correspond to the cytopathologic findings in aspiration cytology. Intracytoplasmic vacuoles exhibit variable shapes: prominent intracytoplasmic vacuoles (B), a protruding vacuole beyond the cytoplasmic border (C), and several small vacuoles encircling the nuclei to form a band-like appearance (D). Perinuclear clearing is identified circumferentially (F, G) or sectionally (H). Condensed juxtanuclear cytoplasm with nuclear indentation makes a rhabdoid appearance (J, K). Intracytoplasmic degenerative red blood cells (L, arrow) are present (B-D, F-H, J-L, Papanicolaou stain).
Fig. 3Variable nuclear features in aspiration cytology by liquid-based preparation (LBP) of mediastinal lymph nodes. (A) Tumor cells show binucleated, large nuclei with irregular borders. Many small vacuoles are present in the cytoplasm. (B) Tumor cells show markedly irregular nuclei with prominent nucleoli, resembling Reed-Sternberg cells (A, B, Papanicolaou stain).