Prospective study comparing acute toxicity and objective response rate between simultaneous integrated boost and...

Patients with locally advanced head and neck squamous cell carcinoma (HNSCC) were included for evaluation of patient characteristics, dosimetric analysis, and plan evaluation of both intensity-modulated radiotherapy (RT) using simultaneous integrated boost (SIB-IMRT) and sequential IMRT (IMRTSEQ) and to compare the response and acute toxicity of both arms. This prospective single-blind randomized clinical comparative study was carried out on 60 patients, clinically and histologically confirmed to have locally advanced HNSCC at the Clinical Oncology Department, Tanta University Hospitals. All patients were randomly divided into two equal groups: Group A was treated with SEQ-IMRT with combined total doses in phases I, II, and III of 70 Gy/35 fractions, 2 Gy/fraction along the entire course, 5 days a week, in 7 weeks by 54 Gy in 27 fractions, and group B was treated with SIB-IMRT dose of 66 Gy to PTV-HR (2.2 Gy/fraction), 60 Gy to PTV-IR (2 Gy/fraction), and 54 Gy to PTV-LR (1.8 Gy/fraction), all were given at the same time in 30 fractions, 5 days a week, over 6 weeks. All patients received 3 cycles of induction chemotherapy with docetaxel (or Taxotere), platinum, and 5-fluorouracil, followed by concurrent chemo-RT with cisplatin or carboplatin. Organ at risk )OAR( was higher for group B (100%) vs. (33.3%) for group A (p = 0.035). The 1-year & 2-year OS for the whole group were (98.3% & 61.5%) respectively, while for group A and group B, 1-year OS was 96.7% for group A vs. 100.0% for group B, and the 2-year OS was 53.2% for group A vs. 71.2% for group B. the 2-year PFS was 58.3% for the whole group and 49.4% vs. 69.2% for groups A and B, respectively. The SIB-IMRT arm, with shorter total treatment duration, resulted in comparable treatment outcomes and acute toxicity rates. This reduction in treatment time not only reduces costs but also decreases the workload of busy radiation. The SIB-IMRT is well-tolerated with better treatment compliance for head and neck cancer patients.