Radiation therapy for early glottic carcinoma (T1N0N0). The adverse effect of treatment interuption

In 253 patients administered 60 Gy in 30 fractions, 77 patients had no gap and were treated within 6 weeks (Group I), although prolongation of overall treatment time occurred in 176 patients, i.e., 141 patients treated within 7 weeks (Group II) and 35 patients within 9 weeks (Group III). The 3-year recurrence free survival rates were Group I: 95%, Group II; 89% and Group III; 80%. There was significant difference between groups I and III (p=0.0156). Concerning tumor clearance at 40 Gy prolongation of overall treatment time for more than 7 weeks affects the local control in incomplete clearance cases but not in complete clearance cases. (author)