ORIGINAL ARTICLE PHASE II CLINICAL TRIAL OF PARENTERAL HYDROXYUREA AND HYPERFRACTIONATED, ACCELERATED EXTERNAL BEAM RADIATION THERAPY IN PATIENTS WITH ADVANCED SQUAMOUS CELL CARCINOMA OF THE HEAD AND NECK: TOXICITY AND EFFICACY WITH CONTINUOUS RIBONUCLEOS

Abstract: Background. Almost all concurrent chemoradia-tion regimens for head and neck are platinum based; how-ever, cisplatin is associated with severe renal, oto-, and neurotoxicity. Hydroxyurea (HU) has been associated with fewer irreversible toxicities. We obtained HU in parenteral form to be administered continually during the radiation treatment. Intravenous HU promised better pharmacokinetics and cell cycle blockade. Methods. Participants had biopsy-proven, untreated squa-mous cell carcinoma of the oral cavity, oropharynx (stage IV) and hypopharynx (stages II–IV). Radiation therapy consisted ini-tially of 74.4 Gy administered in twice daily 1.2-Gy fractions. Af-ter 20 patients, the radiation dose was reduced to 60.0 Gy, and another 16 patients were enrolled. Results. Patients received HU by Continuous Ambulator