Asteroid bodies in lymph node cytology: infrequently seen and still mysterious.

Granulomatous inflammation is a relatively common finding in routine aspiration cytology of lymph nodes. However, asteroid bodies are very rarely encountered in cytologic preparations, and most morphologic descriptions result from observations made in histologic tissue sections. This brief report describes the cytologic findings in paratracheal aspirate smears from a 74-year-old Caucasian woman with the history of squamous-cell carcinoma of the right ankle metastatic to a right groin lymph node. At the time of removal of the metastatic tumor, the patient was noted to have multiple small, mildly FDG-avid lymph nodes in the supraclavicular, paratracheal, precarinal, pulmonic hilar, and axillary regions. A transbronchial fine-needle aspiration biopsy (FNAB) of a paratracheal lymph node showed granulomatous inflammation and numerous multinucleated giant cells containing asteroid bodies. No evidence of malignancy was present in any of the smears. Additional patient history elicited at the time of FNAB revealed a diagnosis 6 years previously of disseminated histoplasmosis infection. A concomitant workup for sarcoidosis was negative.