Office-based 532-nm KTP laser as a therapeutic modality for recurrent laryngeal papillomatosis: efficacy and relative factors

This study aims to investigate the efficacy of office-based potassium-titanyl-phosphate (KTP) 532-nm laser in the management of recurrent laryngeal papillomatosis (RLP) following other treatments. A retrospective assessment was performed on 55 patients in 259 cases of RLP between 2012 and 2019. Derkay scores were obtained for all patients who underwent 532-nm KTP laser procedure (6 W of power with a continuous output mode) prior to treatment and after treatment. Analysis of parameters is based on the distribution characteristics of data. An ordinal logistic regression was also performed. Patients received a median of 3 (range 1-24) office-based KTP laser treatments. Among them, 96.36% (53 patients) were previously on cold steel equipment, CO2 laser, or microdebrider treatment under general anesthesia, and all previous treatments on them had failed. One patient progressed to invasive cancer, so he was excluded from the following analyses. After final KTP treatment, 36 patients (66.67%) received complete resolution with follow-up time ranging from 12.9 to 80.53 months (median 55.54 months). Results of subjective voice-quality indicators such as VHI-30 and GRBAS all improved greatly at the last follow-up. The initial Derkay scores and treatment intervals were found to be predictive of complete lesion remission. Arytenoid involvement may also correlate with lesion resolution. Serial office-based KTP treatment is an effective option for RLP patients, with ideal disease control and voice quality preservation. KTP laser therapy should be repeated with an interval of 1 month from the beginning of treatment until the lesion has been evaluated and subsided. Non-bulk or scattered laryngeal papilloma is an appropriate indication for KTP laser treatment.