Nasopharyngeal carcinoma in a low incidence European area : A prospective observational analysis from the Head and Neck Study Group of the Italian Society of Radiation Oncology (AIRO)

Abstract

Purpose: To evaluate the outcomes with respect to long-term survival and toxicity in patients with nasopharyngeal carcinoma (NPC) treated in a European country with low incidence.

Materials and methods: A prospective observational study carried out by the AIRO Head and Neck group in 12 Italian institutions included 136 consecutive patients treated with radiotherapy (RT) ± chemotherapy (CHT) for NPC (without distant metastasis) between January 1, 2008 and December 31, 2010.

Results: The disease-specific survival (DSS), overall survival (OS), and disease-free survival (DFS) at 5 years were 92 (±2), 91 (±3), and 69 % (±5 %), respectively. Distant failure was the most frequent modality of relapse. The local, regional, and locoregional control at 5 years were 89 (±3), 93 (±3), and 84 % (±4 %), respectively. The incidence of acute and late toxicity and the correlations with different clinical/technical variables were analyzed. Neoadjuvant CHT prolongs radiotherapy overall treatment time (OTT) and decreases treatment adherence during concomitant chemoradiotherapy. An adequate minimum dose coverage to PTV(T) is a predictive variable well related to outcome.

Conclusion: Our data do not substantially differ in terms of survival and toxicity outcomes from those reported in larger series of patients treated in countries with higher incidences of NPC. The T stage (TNM 2002 UICC classification) is predictive of DSS and OS. The GTV volume (T ± N) and an adequate minimum PTV(T) coverage dose (D95 %) were also identified as potential predictive variables. Sophisticated technologies of dose delivery (IMRT) with image-guided radiotherapy could help to obtain better minimum PTV(T) coverage dose with increased DFS; distant metastasis after treatment still remains an unresolved issue.

Keywords: Chemotherapy; Prognosis; Radiotherapy; Survival; Toxicity.