Cytological diagnosis of osteoblastoma of the talus: Case report with unusual presentation and diagnostic pitfalls

Osteoblastoma is a rare bone tumor mostly affecting the young adults and commonly involving the spinal cord and long bones. Talus is the uncommon site of presentation, and if involved, then the neck is more commonly involved than the body of talus. The cytological diagnosis of osteoblastoma is limited, and to the best of our knowledge, its fine-needle aspiration (FNA) in the talus has still not been reported in the literature. The present case of osteoblastoma is, therefore, being reported due to the unusual presentation in elderly male in the body of talus and showing extensive involvement on X-ray. The case was initially diagnosed on FNA cytology excluding the possibility of giant-cell tumor and osteosarcoma. The case also highlights the importance of vigilant observation of subtle cytological features of this rare tumor which may be helpful in avoiding diagnostic pitfalls, especially at an uncommon site and with unusual presentation. An early precise diagnosis by cytology may be followed by appropriate treatment and thus avoiding any further complications.