Volumetric modulated arc therapy versus tomotherapy for late T-stage nasopharyngeal carcinoma

Abstract

PurposeTo compare the dosimetric parameters and clinical outcomes between volumetric modulated arc therapy (VMAT) and tomotherapy for treating late T-stage nasopharyngeal carcinoma (NPC).MethodsPatients with non-metastatic late T-stage NPC who received definitive radiotherapy with tomotherapy or VMAT were selected. 1:1 propensity score matching (PSM) was used to control the balance of confounding factors. The dosimetric parameters and clinical outcomes were compared.ResultsA total of 171 patients were enrolled before matching, with 61 patients in the VMAT group and 110 patients in the tomotherapy group. In the post-PSM cohort, 54 sub-pairs of 108 patients were included after matching. Tomotherapy was superior to VMAT in the dosimetric parameters of planning target volumes, brainstem, spinal cord, lenses, and parotid glands but inferior in the optic nerves and optic chiasm. The tomotherapy group had a lower incidence of grade ≥ 3 acute mucositis (22.2% vs. 40.7%, p = 0.038) and a higher rate of complete response (83.3% vs. 66.7%, p = 0.046) after radiotherapy. However, there were no significant differences in locoregional failure-free survival (p = 0.375), distant metastasis-free survival (p = 0.529), or overall survival (p = 0.975) between the two groups.ConclusionTomotherapy is superior to VMAT in terms of most dosimetric parameters, with less acute mucositis and better short-term efficacy. There are no significant differences in the survival outcomes between the VMAT and tomotherapy groups.

Locally advanced nasopharyngeal carcinoma in adolescents treated with tomotherapy: Experience at King Faisal Specialist Hospital and Research Centre

“…We report grade 1 salivary toxicity as an acute side effect in 64.7%. These figures are comparable with the results of study done by Chen et al 8 …”

“…Helical radiotherapy has been used in the past decade as the preferred option due to its dosimetric advantage over IMRT and VMAT techniques. 8 Its use has been increasingly adopted in head and neck cancers and especially for patients with NPC. Due to the great outcome in terms of survival for these patients, late toxicity has been a genuine concern.…”

“…Therefore, the feasibility of delivering such treatment with these newer techniques is now deemed safe with excellent long-term side effects as already demonstrated in multiple dosimetric studies and in comparisons of their clinical outcomes. 8 , 20 , 21 …”

“…It has a lower incidence of mucositis and other short-term side effects, with no significant differences in the survival outcome between these two modalities of treatment. 8 …”