Lack of Prognostic Effect of Carbonic Anhydrase-9, Hypoxia Inducible Factor-1α and Bcl-2 in 286 Patients with Early Squamous Cell Carcinoma of the Glottic Larynx Treated with Radiotherapy

High CA-9, HIF-1α and Bcl-2 do not add to the prognostic significance of tumour stage and lower haemoglobin in predicting failure of local control in early glottic larynx squamous cell carcinoma managed with radiotherapy. The effect of haemoglobin was not strong enough to be useful as a prognostic biomarker.