[Fine needle biopsy in the preoperative diagnosis of parotid tumors]

Fine-needle aspiration biopsy is of particular interest in the parotid sites because, here, pathology with different treatments and prognosis manifest themself in the same way. The preoperative diagnosis of neoplasm is often problematic. As is known, this is correlated to several factors including histology, clinical and instrumental semiology. The instrumental image techniques (sialography, thermography, scintigraphy, ultrasound diagnosis, tac sialo-tac) give information as to size and location of the mass in question. Only rarely does it give any indication of whether the mass is malignant or benign. The authors systematically studied 386 parotid tumors. The method utilises a traditional technique (needle n. 12/2 gauge 1/4) and microscope examination with immediate dyeing to verify the correctness of the sample. 352 cases underwent surgery with subsequent histological verification. The results demonstrated a generical concordance of cytology and histology in the diagnosis of malignancy equal to 95%. The concordance of exact histology was 91%. The discordance regards, above all, the malignant neoplasm and particularly the mucoepidermoide and the adenoid cystic carcinoma. Fine needle aspiration demonstrates absolute specificity in the differential diagnosis between parotid and extraparotid pathology.