Impact of chemotherapy compliance on the therapeutic efficacy of patients with locally advanced nasopharyngeal carcinoma

Objective To evaluate the impact of chemotherapy compliance on the therapeutic efficacy of induction chemotherapy plus concurrent chemoradiotherapy versus induction chemotherapy plus radiotherapy alone for patients with locally advanced nasopharyngeal carcinoma （ NPC ）. Methods Based on intention to treat analysis （ITT） for 400 patients, 314 patients were analyzed by per protocol （PP） analysis. The patients were divided into induction chemotherapy plus concurrent chemoradiotherapy group （IC/CCRT, 127 patients） or induction chemotherapy plus radiotherapy group （IC/RT, 187 patients）. The patients who completed 2 cycles of induction chemotherapy and at least 2 cycles of concurrent chemotherapy in the IC/CCRT group and the patients who completed 2 cycles of induction chemotherapy in the IC/RT group were analyzed. Radiotherapy was given by two-dimensional technique with γ-ray. X-ray and electron beams. The chemotherapy regimen was FUDR plus carboplatin for induction chemotherapy and carboplatin alone for concurrent chemotherapy. Results The follow-up rate was 96.2%. 295 patients were followed to at 3 years. Based on PP analysis, Grade 3/4 toxicity was found in 23.6% of the patients in IC/CCRT group and 13.4% in the IC/RT group （χ^2 = 5.50, P = 0. 019）. No grade 4 toxicity was found in the IC/RT group. The median follow-up time was 3.9 years, and no significant difference was found between the two groups in 3-year overall survival （78.1% ： 84.6% ;χ^2 =0.61 ,P =0. 435） , disease-free survival （74.3% ： 70. 1% ; χ^2 = 0. 12, P= 0.731 ）, locoregional relapse-free survival （89.7% ： 89.5% ; χ^2 = 0. 10, P= 0.748） , or distant metastasis-free survival （78.9%： 76.5% ;χ^2 =0.05,P=0.825）. Condusions With more severe toxicities, the IC/CCRT regimen does not improve the overall survival in locally advanced NPC patients compared with the IC/RT regimen. Key words: Nasopharyngeal neoplasms/chemoradiotherapy ;  Radiotherapy, two-dimensional ; Chemotherapy,induction ;  Chemotherapy,concurrent ;  Prognosis