Vocal fold vibration after photofrin-mediated photodynamic therapy for treatment of early-stage laryngeal malignancies

Abstract

Objective/hypothesis: To analyze vocal fold vibration after photofrin-mediated photodynamic therapy (PDT) for the treatment of Tis and T1N0M0 squamous cell carcinoma (SqCCa) tumors of the larynx. It was hypothesized that key attributes of vocal fold vibration would return to baseline within 1-6 months of treatment.

Study design: Retrospective.

Methods: Laryngovideostroboscopic data were retrospectively analyzed for eight patients with Tis-T1N0M0 SqCCa tumors of the larynx treated with photofrin-mediated PDT. Baseline and posttreatment videostroboscopy images of select vibratory characteristics of the vocal folds were randomized and analyzed by a speech-language pathologist and fellowship-trained laryngologist specializing in voice disorders.

Results: Significant improvement in mucosal wave (P=0.003) and amplitude of vibration (P=0.004) occurred at greater than or equal to 20 weeks post-PDT compared with baseline. Comparing results within 5 weeks postprocedure to 10-19-weeks postprocedure revealed significant improvement in amplitude of vibration (P=0.013) and nonvibrating portion of the vocal fold (P=0.020). Comparing results within 5-weeks postprocedure to 20 or more weeks postprocedure revealed significant improvement in amplitude of vibration (P=0.001), mucosal wave (P=0.001), and nonvibrating portion of the effected fold (P=0.001).

Conclusion: Photofrin-mediated PDT allows for preservation of function and structure of the larynx without systemic toxicity; however, it may take 4-5 months or more for key vibratory characteristics of the vocal folds to recover posttreatment.

Keywords: Larynx; Photodynamic therapy; Photofrin; Videostroboscopy; Vocal fold vibration.