Sustained improvement of quality of life for nasopharyngeal carcinoma treated by intensity modulated radiation therapy in long-term survivors.

UNLABELLED IMRT has achieved an excellent survival and less radiation-induced sequelae with improvement of QoL within 2 years compared to conventional radiotherapy for NPC. Whether IMRT could sustained decrease incidence of late sequelae and improve QoL further for long-term survivors remained unknown. 176 patients from Aug. 2002 to Jun. 2009 were retrospectively analyzed. Radiation-related toxicities were graded according to both the Acute and the Late Radiation Morbidity Scoring Criteria of the EORTC/RTOG; QoL was assessed by the EORTC QLQ-C30 and H&N35 questionnaires at 5 and 8 years. The 5-year overall survival rate was 68.2% with a median follow-up time of 86 months. The most common radiation-related acute and late toxicity was xerostomia, the incidence of Grade ≥ 1 xerostomia was 90.3%, 84.1%, 75.9% and 59.2%, respectively at acute, 6 months, 2 years and 5 years. Statistical analysis indicated a close relationship between 5 years with 6 months and 2 years for patients who had ≥ 3 xerostomia at acute phase (r = 0.538 for late xerostomia at 6 months with 5 years, r = 0.732 for 2 years with 5 years); Sustained amelioration of other sequelae was also observed; QoL questionnaires at 5 years showed a significant improvement of most items and got stable between 5 to 8 years. IN CONCLUSION IMRT could sustain reduce late radiation sequelae and improve QoL for long-term survivors over time; Patients with severe acute xerostomia (≥ grade 3) would have a significant correlation of mitigatory xerostomia during the late follow-up time.