Nasopharyngeal biopsy imprint cytology: a retrospective analysis of 191 cases

Patients with nasopharyngeal carcinoma (NPC) are common in Taiwan. To provide efficient management to patients, the surgeons often perform cytological imprints immediately after biopsies of lesions suspicious for NPC. The results of cytological assessment of imprints usually are reported within 30 min after biopsies. The patients with positive cytological results can then be arranged for further examinations during the same visit. We reviewed 191 imprints and corresponding biopsies from 187 patients during 1997-2004 at Koo Foundation Sun Yat-Sen Cancer Center, Taipei. The cytological diagnoses were categorized into four groups: negative (62 cases), suspicious (8 cases), positive (116 cases), and inadequate specimen (5 cases). There were 18 false-negative and 1 false-positive diagnoses. All suspicious cases were positive histologically. Our results showed a sensitivity of 87.2% and a specificity of 97.8%. The accuracy was 89.8%. Therefore, nasopharyngeal imprint cytology is a sensitive and specific method for rapid diagnosis of nasopharyngeal cancer at an outpatient setting.