The purpose of this retrospective study was to report on the efficacy of radiotherapy alone in patients with T4-stage laryngeal cancer and to establish the prognostic value of (a) the size and location of the extralaryngeal tumor extensions and (b) of emergency tracheostomy. A group of 114patients were treated with definitive radiotherapy between 1990 and 1996. The piriform recess was involved in 37cases (33 %), the base of the tongue and glosso-epiglottic vallecula in 34cases (30 %), and the hypopharyngeal wall in 10cases (9 %). In 16 cases (14 %), emergency tracheostomy was performed before radiotherapy. The mean total dose was 68Gy (range, 60-77.6Gy). The mean treatment time was 49days (range, 42-74days). Actuarial 3-year local control (LC) was noted in 42 % of patients, disease-free survival (DFS) in 35 %, and overall survival (OS) in 40 %. The best prognosis was for the lesion suspected of cartilage infiltration: 56 % 3-year LC. The worst results were noted in the cases with massive infiltrations spreading from the larynx through the hypopharynx: 13 % 3-year LC. Emergency tracheostomy before radiotherapy was significantly connected with the worst treatment results (p = 0.000): 3-year LC in patients with tracheostomy was 0 % vs. 48 % in patients without tracheostomy. Conventional radiotherapy of T4 laryngeal cancer is a method of treatment with limited effectiveness. The efficacy of radiotherapy is dependent on the location and extent of extralaryngeal infiltrations. Emergency tracheostomy is a prognostic factor connected with the worst prognosis.