Utility of cell block in the cytological preoperative diagnosis of keratocystic odontogenic tumor.

In most cases involving jaw lesions, a biopsy and a histopathological analysis are necessary to establish the final diagnosis. However, biopsy may be a complex procedure at some maxillomandibular sites, and some systemic conditions could contraindicate the procedure. Thus, a search for new, less invasive techniques, which could eventually replace biopsy and simplify the diagnostic process, would benefit both professionals and patients. The aim of this study was to evaluate the cell block technique, prepared from the aspiration of luminal contents, in the preoperative diagnosis of keratocystic odontogenic tumors (KCOT). From 135 cases of lesions aspirated and processed by the cell block technique, we selected those containing keratin. In all cases selected, histological diagnosis was based on surgical biopsy. From 20 cases containing keratin in the cytological analyses, 19 were KCOTs and one was an orthokeratinized odontogenic cyst (OOC). In all KCOT cases, we observed the presence of parakeratin, even in those with intense inflammation. In the cytological analysis of the OOC, parakeratin was not observed. In conclusion, there is strong evidence that KCOT can be confidently diagnosed preoperatively by cytological analyses of lesions punctured and processed by the cell block technique.