Immediate interpretation of FNA smears from the head and neck region.

FNA smears from 540 patients, investigated for visible and/or palpable lesions in the head and neck, examined immediately during consultation have been compared with the final cytologic diagnoses and, when possible, with histologic results. Preliminary and final cytologic diagnoses differed in 25 cases (4.6%). Major discrepancies as to whether a lesion was benign or malignant occurred in 15 cases (2.8%). Histologic follow-up was available for 188 lesions (35%). There were 5 false-positive (2.6%) and 9 false-negative (4.7%) diagnoses, giving a sensitivity of 90.6% and a specificity of 94.6%. The main diagnostic problem was benign, reactive lymphadenitis versus malignant lymphoma, which was responsible for 11 of 14 erroneous cytologic diagnoses (3 false-positive and 8 false-negative smears).