The predictive value of videostroboscopy in the assessment of premalignant lesions and early glottis cancers

Abstract

Objective: To assess the sensitivity and specificity of larngovideostroboscopy (LVS) in the diagnosis of precancerous and malignant lesions of the vocal folds. Material and methods: In 175 patients (128 men and 47 women), aged 19-88 years, mean age 61.5, who were admitted to the clinic with diagnosed premalignant conditions of vocal fold mucosa (leukoplakia, chronic hypertrophic inflammatory lesions) and thickening or tumor on the vocal fold, there was performed LVS before the laryngeal microsurgery. The LVS study included: localization of the leasion, movement of the vocal folds, mucosal wave, shape of glottis clousure, amplitude and symmetry of vocal fold vibration. In the evaluation, a point scale was applied for the individual functional parameters. The scale ranged from 0 to 14. Patients with impaired vocal fold motion or absent mucosal wave were positive on LVS for malignant lesions. Those with limitted mucosal wave were positive on LVS for dysplastic lesions. The results were compared with the final histopathological examination and the sensitivity, specificity, accuracy, positive (PPV) and negative (NPV) predictive value were calculated. Results: On the basis of histopathological examination, benign lesions (normal or inflammatory mucosa) accounted for 20% of diagnoses, hypertrophy and parakeratosis for 28%, low and middle grade dysplasia accounted for 10% and malignant lesions (high-grade dysplasia, pre-invasive cancer, Invasive cancer) was diagnosed in 42% of patients. The overall mean score for LVS was 4.5 and 8.0, respectively for benign and malignant lesions. Sensitivity, specificity, accuracy, PPV and NPV of LVS in detecting malignant lesions were respectively - 95.6%, 23.8%, 61.1%, 57.6% and 83.3% and in detecting both premalignant and malignant lesions were respectively – 90.7%, 31.4%, 78.9%, 84.1% and 45.8%. Conclusions: Because of the high sensitivity of LVS in detecting precancerous and malignant lesions, this method is a very good tool for screening of pathology within the larynx.