Treatment of Locally Advanced Nasopharyngeal Carcinoma by Helical Tomotherapy: An Observational, Prospective Analysis

Nasopharyngeal carcinoma (NPC) is endemic in southern China. Due to the unique anatomical and biological properties of NPCs, radiotherapy or combined modality based on radiotherapy is an effective treatment option. Helical tomotherapy (HT) is an emerging intensity modulated radiotherapy technology. The advantages of dose homogeneity, steepness of dose gradient, and protection of normal organs are reflected in the treatment of head and neck cancers. We present the preliminary (2-year) clinical outcomes of HT in 85 patients with locally advanced NPC (LA-NPC). Of these patients, 3 patients (3.5%) experienced treatment interruption due to severe pulmonary infection, and 82 (96.5%) completed radiation treatments. The 2-year estimate of progression-free survival, local relapse-free survival, nodal relapse-free survival, distant metastases-free survival, and overall survival rate were 90%, 96.3%, 98.8%, 96.3%, and 96.3%, respectively. Among the three patients that died, one had stage III disease and died from fatal nasopharyngeal bleeding after radiotherapy, while the other two patients succumbed to local recurrence. Our experience suggests that HT can achieve promising disease control and survival in the treatment of LA-NPC patients with mild acute and late toxicity profiles.