Definitive Radiotherapy for Carcinoma In Situ of the True Vocal Cords

Purpose: To report long-term rates of tumor control after radiotherapy (RT) for carcinoma in situ (CIS) of the true vocal cords (TVC). Materials and Methods: Thirty-seven patients with CISof the TVC were treated curatively with megavoltage RT between July 1967 and December 2005. Most patients (28/37) were treated with cobalt-60; the remainder were treated with 2- to 6-MV photons, Small (usually 5 x 5) fields were used. Median RT dose was 60.0 Gy (range, 56.25-66.50 Gy; mean dose, 59.55 Gy) at 2.25 Gy per fraction. Approximately two-thirds of the patients (23/37) were referred for RT because of a recurrence after at least 1 stripping procedure. Results: With a mean follow-up of 9.5 years (range, 2-25 years), the 5-year rates of local control, local control with larynx preservation, and ultimate local control (including salvage surgery) were 91% 91%, and 91% respectively Invasive squamous cell carcinoma developed in 4 patients (11%). Time to failure was 6 months. 12 months, 48 months, and 13 years. Two patients were surgically salvaged with a total laryngectomy, 1 with transoral laser excision, and 1 patient declined further treatment. Cause-specific survival at 5 years was 100%. No late complications were noted. Conclusions: RT to approximately 63 Gy at 2.25 Gy per fraction. using small (5 x 5cm) fields produces excellent results in patients with CIS of the TVC.