Prognostic factors in telecobalt therapy for early supraglottic carcinoma.

Abstract

The local control rates of T1 and T2 supraglottic carcinoma treated with radiation alone were reported as 71% to 92% and 59% to 83%, respectively. The factors that affect the local control rate for early supraglottic carcinoma were investigated. From 1967 through 1985, 100 cases with early supraglottic carcinoma (T1N0, 51; T2N0, 49) were treated with telecobalt therapy at the Department of Radiology, Osaka University Hospital. The 5-year actuarial survival rates of cases with T1 and T2 were 69% and 74%, respectively. The 5-year local control rates of cases with T1 and T2 were 77% and 62%, respectively. The local control rate for the epilarynx (94%) was significantly better than that for the lower supraglottis (66%; P < 0.05). For the lower supraglottis, the local control rates of 24 tumors that disappeared at 40 Gy and 58 tumors that persisted at 40 Gy were 88% and 55%, respectively (P < 0.05). The tumor site was an important prognostic factor in radiation therapy for the supraglottis, as was the tumor response at 40 Gy for the lower supraglottis.