Truths and Myths About Radiotherapy for Verrucous Carcinoma of Larynx

Purpose The role of primary radiotherapy (RT) for laryngeal verrucous carcinoma (LVC) is controversial because of concerns about anaplastic transformation, an increased incidence of metastases, and poorer local control after RT. To address these concerns, we report our experience. Methods and Materials All patients with pathologically diagnosed LVC treated with primary RT at our institution between 1961 and 2004 were reviewed. The local control, overall survival, and disease-specific survival rate were established. The outcome after salvage treatment and the incidence of metastases and anaplastic transformation were determined. Results Of 62 LVC patients with a minimal follow-up of 2 years, 20 local and 1 nodal recurrence were identified. Salvage surgery was undertaken in 18 of the 21 patients, and disease control was achieved in 17; the eighteenth patient died of a complication after surgery. Ultimate laryngeal preservation was achieved in 50 patients (81%), including 42 after initial RT and an additional 8 after salvage surgery. Distant failure and anaplastic transformation were not observed. Second cancers after RT were identified in 4 patients, only 1 of which was a head-and-neck cancer detected 11 years later. Of the 39 deceased patients, only 3 died of LVC. The local control, overall survival, and disease-specific survival rate at 5 years was 66% (95% confidence interval, 52–77%), 87% (95% confidence interval, 75–93%), and 97% (95% confidence interval, 87–99%), respectively. Conclusion The results of our study have shown that the initial control of LVC with RT is less reliable compared with reports from surgical series; however, local recurrence was almost always salvaged successfully, resulting in disease-specific survival rates equivalent to those of surgical series. Neither anaplastic transformation nor unusual metastasis development was observed in this series.