Fine needle aspiration diagnosis of transitional cell carcinoma metastatic to the brain. A case report

BACKGROUND: Transitional cell carcinoma (TCC) rarely metastasizes to the brain. In this case, aspiration of a cystic brain lesion was performed and a cytologic diagnosis made. To the best of our knowledge, this is the first reported case of TCC metastatic to the brain diagnosed by fine needle aspiration. CASE: A 72-year-old male with a past medical history of invasive TCC, colonic adenocarcinoma and prostatic adenocarcinoma presented with a large, right, temporal, cystic mass. Fine needle aspiration was performed intraoperatively, and a cytologic diagnosis of metastatic TCC was rendered and confirmed by subsequent tissue examination. CONCLUSION: Intraoperative fine needle aspiration of cystic tumors can be useful in identifying the primary site. The cytologic features of intracerebral metastatic TCC can differ significantly from those observed in urinary tract specimens of high grade TCC. A predominance of large fragments of malignant cells with numerous mitotic figures and apoptotic bodies was seen in the former. The background showed high grade, single transitional cells similar to those observed in urinary tract samples of TCC.