Diagnostic pitfalls in fine-needle aspiration cytology of temporomandibular chondroblastoma: report of two cases.

Chondroblastoma is a benign bone neoplasm, which usually presents in the epiphysis of long bones, but can occur in unusual locations. This report describes the clinical, radiologic, and cytologic features on FNA of two chondroblastomas of the temporomandibular region that were only recognized by histopathologic study. This emphasizes the diagnostic pitfalls of this entity and expands the cytologic differential diagnosis of tumors of the parotid region.

Is preoperative cytologic diagnosis of epithelioid sarcoma possible?

Epithelioid sarcoma (ES) is a rare malignant neoplasm of the soft tissues with a predilection for distal extremities of young adults. A "proximal" variant was recently described. The preoperative fine-needle aspiration cytology (FNAC) differential diagnosis with necrotizing granuloma, carcinoma, melanoma, and other neoplasms with epithelioid morphology can be difficult and few cases have been described in the literature. The authors present the preoperative FNAC findings of 10 aspirates of ES, corresponding to seven patients (four men and three women, ages 13-72 years). The cytologic features were compared with histologic features as well as with the FNA patterns of other neoplasms with epithelioid morphology that may be included in the differential diagnosis. Cytologic smears showed tumor cells with an epithelioid to spindle cell morphology, dispersed and in loose clusters in close relation with a fibrillar hyaline material. The cells showed moderate anisocariosis, a vast well-defined, often dense cytoplasm with immunoexpression of vimentin, cytokeratin, and CD 34. When the FNA cytologic features described above are accompanied by the adequate clinical setting and are supported by immunocytochemistry, an accurate preoperative cytologic diagnosis of ES is possible.