Early-stage glottic carcinomas: effect of tumor location and full-length involvement on local tumor recurrence after radiation therapy.

Abstract

To correlate tumor location along the vocal cord with local control in stage I and II glottic carcinoma. Sixty-five patients with stage I and 18 patients with stage II glottic cancer were irradiated with 4-MV x rays. Most patients received a total of 64-66 Gy, at a dose of 1.8-2.0 Gy/d. In stage I tumors, local-control probability was 96% +/- 2 (standard deviation); in stage II tumors, 67% +/- 15. When stages I and II were considered together, tumors that involved the full length of the vocal cord were more likely to recur (P = .069). In stage I tumors, treatment with < 2.0 Gy/d was statistically significantly (P = .038) associated with local recurrence. Poor outcome after irradiation could not be predicted with involvement of either the anterior commissure or posterior third of the vocal cord. Risk of tumor recurrence increased with full-length involvement, and in stage I tumors, with a daily fraction < 2.0 Gy.