IMMUNOHISTOCHEMICAL CHARACTERIZATION OF BENIGN LARYNGEAL LESIONS

It has been proposed that laryngeal nodules and polyps represent injur y to the basement membrane zone of the vocal fold. Repeated trauma fro m shearing forces produced by excessive or abusive phonation lends to basement membrane zone disruption and thickening. This thickening, alo ng with poorly understood vascular changes, creates the characteristic clinical appearance of the vocal nodule or polyp. As such, to better understand vocal fold nodules it is imperative to characterize the ext racellular matrix in this area of injury. Secondary to the small size and relatively acellular nature of these lesions, hematoxylin and eosi n (H & E) preparations of histologic material are unsatisfying. A prev ious study examined this area with immunohistochemical techniques to b etter characterize its contents. The report, however, contained little information with regard to the clinical appearance of the lesions pri or to excision. Therefore, we were prompted to review histologic mater ial from 31 patients who underwent microsurgical excision of 41 benign lesions, vocal nodules (4), polyps (19), polypoid corditis (4), and c ysts (14) with immunohistochemical techniques to characterize the patt erns of fibronectin and collagen type IV within these lesions. Normal human vocal folds were stained for control. All material was correlate d with the H & E preparations and the clinical diagnosis. Collagen typ e IV and fibronectin appeared present in relatively abnormal patterns in the areas adjacent to the lesion. This study validates earlier resu lts. In addition, correlation with clinical data allows association of immunohistochemical staining patterns with clinical diagnosis.