Volumetric modulated arctherapy for locally advanced nasopharyngeal carcinoma: Clinical efficacy and late toxicity

We report our experience of 86 consecutive patients with locally advanced nasopharyngeal carcinoma who were treated with volumetric modulated arc therapy.

We retrospectively reviewed the medical records of 86 patients with histologically proven primary nasopharyngeal carcinoma treated with volumetric modulated arctherapy technique radiotherapy. Primary endpoints were local, regional, distant control, and overall survival, second endpoint was late toxicity.

The median age was 47.5 years (range: 13-79 years) with sex ratio 1.09. At diagnosis, rhinologic symptoms represented the most common clinical presentation, reported by 61 patients (70.9%). Almost 88.4% of patients presented non-keratinizing undifferentiated carcinoma histology (n=76). Most of the patients presented a locally advanced disease defined by stage III and IVa (95.3%). Therefore, 31 patients were treated by concurrent chemoradiation (36%), 52 patients received induction chemotherapy followed by concurrent chemoradiotherapy (57%), three patients received induction chemotherapy followed by exclusive radiotherapy (3.5%). and three patients treated with exclusive irradiation (3.5%). With a median follow up of 15.7 months (range: 4-33.3 months), nine patients died (10.4%), three presented local or locoregional relapse (3.4%), while nine patients presented distant recurrences (10.4%). The two years overall and disease-free survival rates were 88.7% and 83.1% respectively, locoregional control was 100% at 12 months and 96.2% at 24 months, and the two years distant failure-free survival was 86.7%. Time to relapse was the only prognostic factor in univariate analysis for overall survival in our study. The therapeutic tolerance was good with 61.7% of grade 3 and 2.3% grade 4 hyposialia respectively, 46.5% of otological disorders and no radionecrosis was noted.

Volumetric modulated arctherapy technique with concurrent chemoradiotherapy is an effective treatment for nasopharyngeal carcinoma with excellent overall and locoregional control without severe toxicity. Distant metastasis is the major site of failure, so induction chemotherapy added to chemoradiotherapy must be discussed in multidisciplinary consultation meeting because it significantly improved recurrence-free survival and overall survival, as compared with chemoradiotherapy alone.