T1-T2N0 squamous cell carcinoma of the glottic larynx treated with radiation therapy

Purpose: The end results after radiation therapy for T1-T2N0 glottic carcin oma vary considerably. We analyze patient-related and treatment-related par ameters that may influence the likelihood of cure. Patients and Methods: Five hundred nineteen patients were treated with radi ation therapy and had follow-up for greater than or equal to 2 years. Three patients who were disease-free were lost to follow-up at 7 months, 21 mont hs, and 10.5 years. No other patients were lost to follow-up. Results: Local control rates at 5 years after radiation therapy were as fol lows: T1A, 94%; T1B, 93%; T2A, 80%; and T2B, 72%. Multivariate analysis of local control revealed that the following parameters significantly influenc ed this end point: overall treatment time (P < .0001), T stage (P = .0003), and histologic differentiation (P = .013). Patients with poorly differenti ated cancers fared less well than those with better differentiated lesions. Rates of local control with laryngeal preservation at 5 years were as foll ows: T1A and T1B, 95%; T2A, 82%; and T2B, 76%. Cause-specific survival rate s at 5 years were as follows: T1A and T1B, 98%; T2A, 95%; and T2B, 90%. One patient with a T1NO cancer and three patients with T2NO lesions experience d severe late radiation complications. Conclusion: Radiation therapy cures a high percentage of patients with T1-T 2NO glottic carcinomas and has a low rate of severe complications. The majo r treatment-related parameter that influences the likelihood of cure is ove rall treatment time.