Cytologic diagnosis of a case of recurrent adamantinoma

The cytologic features of a case of recurrent adamantinoma of the tibia diagnosed by fine needle aspiration (FNA) in a 31-year-old patient are described. The FNA smears contained single-lying cells and cells arranged in small clusters and Indian files, with some nuclear molding. Three cell types were present: (1) large polygonal cells with chromatin clearing, (2) smaller cells with poorly defined cytoplasm and dense chromatin and (3) fusiform cells. The first two were interpreted as epithelial in nature and the third one as being derived from the stroma. These cytologic features appear to be sufficiently characteristic to suggest an FNA diagnosis of adamantinoma, especially in the case of a recurrent tumor.