Reliability of a transnasal flexible fiberoptic in-office laryngeal biopsy

Importance: Transnasal fiberoptic laryngoscopy (TFL) has been used to guide various in-office procedures for the past 3 decades. Publications on in-office laryngeal biopsy have concurred that this procedure is safe, feasible, and easy to perform. However, the accuracy of inoffice biopsy via TFL has not yet been established. The aim of this study was to examine this issue. Objective: To compare pathologic results obtained via in-office TFL with those of subsequent direct laryngoscopy to assess the accuracy of TFL as a diagnostic tool. Design: Prospective cohort study. Setting: Tertiary reference medical center. Participants: One-hundred two patients with suspicious laryngeal lesions. Intervention: All patients underwent in-office biopsies. Main Outcome Measures: All patients with malignant lesions were referred to appropriate services for treatment, and those with a diagnosis of a benign lesion or carcinoma in situ were referred for direct laryngoscopy for definitive diagnosis. The results of the pathologic testing on specimens from in-office and direct laryngoscopy were compared. Results: Adequate tissue for diagnostic purposes was obtained in 96 of 102 in-office TFL biopsies (94.1%). The biopsy results revealed invasive carcinoma in 34 patients (35.4%), carcinoma in situ in 17 patients (17.7%), and benign lesions in 45 patients (46.9%). All patients with benign lesions and carcinoma in situ were referred for biopsy of samples obtained using direct laryngoscopy, to which 57 patients agreed. The final pathologic results identified from the biopsies on direct laryngoscopy revealed that there was an underestimation of the TFL results in 30 of 91 patients (false-negative rate, 33.0%) and an overestimation in 1 patient (false-positive rate, 1.1%). The sensitivity of TFL biopsy compared with that of direct laryngoscopy biopsy was 69.2% and the specificity was 96.1%. Conclusions and Relevance: Transnasal fiberoptic laryngoscopy yielded low sensitivity in assessing suspicious lesions of the larynx. These results may indicate that direct laryngoscopy represents the definitive pathologic diagnostic procedure whenever the pathologic results of an in-office TFL procedure are interpreted as benign or as carcinoma in situ.