Volumetric-modulated arc therapy (VMAT) is an advanced form of intensity-modulated radiation therapy that reduces treatment time without compromising plan quality. This study assessed acute toxicities in patients having carcinomas of oropharynx, larynx and hypopharynx treated with concomitant boost radiation therapy by VMAT.

In this study, 30 patients of stages II–IVA disease were treated with concomitant boost radiation therapy using VMAT and those with stages III and IV also received concurrent chemotherapy with cisplatin 100 mg/m2 weekly thrice for two cycles. The total dose was 68·4 Gy/40 fractions/5.5 weeks (1·8 Gy/fraction/day to the large field for 28 fractions +1·5 Gy/fraction/day to boost field for the last 12 days of treatment). Radiation Therapy Oncology Group acute radiation morbidity scoring criteria was used to grade acute effects.

All patients completed scheduled treatment with median duration of 44 days. No grade 4 skin and mucosal toxicities were observed; grade 3 skin and mucosal toxicities seen in six (20%) and eight (26·67%) patients, respectively; grade 3 dysphagia and laryngeal toxicity in eight (26·67%) and three (10%) patients, respectively; two patients had grade 4 laryngeal toxicity. No grade 3 or grade 4 haematological toxicities were seen.

VMAT-based concomitant boost radiation therapy allows for dose escalation with good patient tolerance by limiting acute toxicities.