Patterns of failure for early-stage glottic carcinoma: 10 years' experience in conformal radiotherapy era

Larynx cancer is the most common head-and-neck cancer in Turkey. Vocal cords are involved nearly 70%-80% of laryngeal carcinomas. We aim to present our 10 years' experience and failure patterns of the patients with T1 and T2 glottic laryngeal carcinoma by same manner, technique, doses, and physician in conformal radiotherapy (RT) era.

Between January 2005 and December 2015, a total of 143 patients treated with definitive RT for early-stage glottis laryngeal cancer were selected. The total dose was 65.25 Gy in 29 fractions.

The median follow-up time was 64 (range: 12-150) months. All of the patients had a complete clinical response to the treatment. A 5-year local control (LC) rates were 84.5%, 91.8%, 74%, and 56% for overall, T1a, T1b, and T2, respectively. Ultimate LC rates (after salvage treatment) for 5 years were 90%, 95%, 92%, and 75% for overall, T1a, T1b, and T2, respectively. Regional neck control for the whole group was 92% for 5 years. After the initial RT, a total of 22 (15.4%) patients had disease recurrence at any site of the neck or larynx. Median time to disease recurrence was 59.5 months (range: 5-150).

This study represents a large and long-term analysis of early-stage glottic carcinoma treated by same manner, technique, doses, and physician in conformal RT era. Definitive RT provides a high LC rate, tolerable toxicity, and favorable voice quality. Extension beyond the vocal cords and T2 stage are the most important unfavorable prognostic factors regarding LC.