The Efficiency of (videolaryngo) stroboscopy in Detecting T1a Glottic Carcinoma and Its Preliminary Stages

The efficiency of laryngovideostroboscopy (LVS) in detecting premalignancies of the vocal fold and early glottic cancer was determined in a prospective monocentric study. In addition, the recovery rate of the mucosal membrane on the vocal fold after surgical intervention was determined by LVS.

We included 159 patients with a leukoplakia of the vocal folds and 50 healthy controls. Clinicopathological data and LVS characteristics (amplitude, mucosal wave, nonvibratory segment, glottic closure, phase symmetry, periodicity) at the lesion site were obtained and compared with the histopathological results. LVS parameters were recorded before cordectomy and in a 12-month follow-up interval. Patients who had prior laryngosurgery, radiotherapy, or laryngeal scarring were excluded.

Absent or greatly reduced mucosal waves were found in all patients with an invasive carcinoma, in 94% with a severe intraepithelial neoplasia (SIN III), in 38% with a moderate squamous intraepithelial neoplasia (SIN II), in 32% with a mild squamous intraepithelial neoplasia (SIN I), and in 23% with a hyperkeratosis without dysplasia. The sensitivity and specificity of LVS in predicting an invasive carcinoma based on the absence or reduction of mucosal waves was 0.96 and 0.90, respectively. Following surgical intervention, the recovery rate of the mucosal wave and amplitude was 12% in the invasive carcinoma group, 36% in the SIN III group and up to 80% for both these parameters in the SIN I, SIN II, and hyperkeratosis groups.

LVS is a valid tool to identify early glottic carcinoma and its high risk premalignancy carcinoma in situ (CIS). Even when there is no definitive differentiation between SIN I and II, the invasive character of a CIS and an invasive glottic carcinoma can be identified. Especially strobosopic signs of abnormal amplitude and/or mucosal waves, particularly phoniatric halt, are an early indication for a CIS or an invasive carcinoma.