Evaluation of Acute Toxicity and Early Clinical Outcome in Head and Neck Cancers Treated With Conventional Radiotherapy and Simultaneous Integrated Boost Arc Radiotherapy.

Background: Chemoradiotherapy plays an important role in management of locally advanced head and neck cancers. This retrospective analysis was done to evaluate and compare acute toxicity profiles and early clinical outcomes in patients treated with conventional and arc techniques.

Methods: Fifty-five patients of head and neck cancers were evaluated. Thirty patients received conventional radiotherapy with 6 MV or cobalt 60 and 25 patients were treated with simultaneous integrated boost-volumetric modulated arc radiotherapy (SIB-VMAT) with dose prescription of 66 - 70 Gy. Concurrent chemotherapy was given as cisplatin injection at 40 mg/m2 weekly or 100 mg/m2 thrice weekly.

Results: The incidence of grade 3-4 mucositis was 56% versus 83.3% with SIB-VMAT and conventional treatments (P = 0.026). The incidence of grade 2-3 xerostomia was 44% versus 80% (P = 0.006) in the two groups. Grade 2 dysphagia was seen in 40% versus 80% (P = 0.008) favoring the arc treatments. Seventeen patients undergoing arc treatment had complete response compared to 14 in the conventional group (P = 0.040). The median disease-free survival (median ± standard error) was 16 months (11 ± 1.987 months) in the conventional and arc groups (P = 0.073).

Conclusion: SIB-VMAT shows a better toxicity profile and a trend towards better disease-free survival when compared to conventional radiotherapy in head and neck cancers.