Evaluation of Reirradiation in Locally Advanced Head and Neck Cancers: Toxicity and Early Clinical Outcomes.

Objectives: Locoregional recurrence is the predominant pattern of treatment failure in advanced head and neck cancers. Reirradiation is a useful modality to treat inoperable head and neck cancer patients with recurrent disease. The aim of the present study was to analyze the treatment toxicity and early clinical outcomes in patients undergoing reirradiation.

Methods: Twenty patients of head and neck cancers with recurrences or second cancers were evaluated. Reirradiation was done using simultaneous integrated boost volumetric modulated arc therapy (SIB VMAT), intensity modulated radiotherapy (IMRT), or conventional radiotherapy using 6MV photons. Dose prescription ranged from 30 to 60 Gy in conventional fractionation.

Results: Seventeen males and three females were evaluated in this analysis. The median age of patients under study was 56.5 years. At time of analysis 8 patients (40%) had a complete response, 7 patients (35%) had progressive disease, and 25% had partial response or stable disease. Grade III-IV mucositis, dermatitis, xerostomia, dysphagia, and trismus were seen in 20%, 20%, 50%, 35%, and 45% patients, respectively, during retreatment. Patients receiving a radiotherapy dose less than 45 Gy showed a higher incidence of progressive disease ( p = 0.01). The median disease-free survival for patients receiving reirradiation dose of ≥46 Gy was 19 ± 3.3 months (median ± S Error) compared to 8 ± 2.61 months for those with a dose prescription less than 45 Gy ( p = 0.03). At 18-month follow-up 26% of patients undergoing reirradiation were disease-free.

Conclusions: Our results show improved tumor control using a prescription of doses ≥46 Gy in retreatment setting.