Comparison Of Weekly And Triweekly Cisplatin Regimens During Concurrent Chemoradiotherapy For Nasopharyngeal Carcinoma

Background: Nasopharyngeal carcinoma(NPC)is a kind of head and neck malignant tumor which occurs frequently in East Asia and Southeast Asia.Concurrent chemoradiotherapy(CCRT)is the standard treatment for NPC patients.We compared the survival outcomes and acute toxicities of weekly and triweekly cisplatin regimens during CCRT in NPC patients.Methods: A retrospective analysis of newly diagnosed patients with stage I-IVA NPC who were treated with CCRT only at the first affiliated hospital of Guangdong pharmaceutical university and Sun yat-sen university cancer center from January 2010 to November 2013.CCRT was initiated on the first day of radiotherapy.Cisplatin 30–40 mg/m2 was infused on days 1,8,15,22,29,36 and 43 in the Weekly Group,while cisplatin 80–100 mg/m2 was delivered on days 1,22 and 43 in the Triweekly Group.Chi-square test or Fisher's exact test was used to compare the baseline characteristics and the incidence of toxic events in the two groups.Survival curves were drawn by Kaplan-Meie method.Survival outcomes were compared using Log-rank test to measure 5-year overall survival(OS),disease-free survival(DFS),local recurrence-free survival(LRFS),and distant metastasis-free survival(DMFS).Cox proportional hazard regression models were used to analyze two groups of clinical variables.Results: A total of 322 patients were included in our research.Ninetythree(28.9%)patients received three to seven cycles of cisplatin weekly(Weekly Group)and 229(71.1%)patients received two to three cycles of cisplatin triweekly(Triweekly Group).There were no statistically significant difference in clinical variables between the two groups.Weekly group 5-year OS was 96.7% and triweekly group 5-year OS was 88.3%(?2 = 4.382,P = 0.036).Weekly group 5-year DFS was 90.7%,triweekly group 5-year DFS was 80.5%(?2= 4.831,P = 0.028).OS and DFS were better in the weekly group than in the triweekly group.The weekly vs.triweekly 5-year DMFS and LRFS rates were: DMFS,96.7% vs.91.4%,?2 = 2.694,P = 0.101;LRFS,96.3% vs.93.5%,?2 = 1.317,P = 0.251.Cisplatin delivery regimen was OS and DFS prognostic factor,but not an independent prognostic factor.For grade 3-4 haematological toxic events including thrombicytapenia(7.5% vs.3.5%,P = 0.120),anaemia(2.2% vs.0.4%,P = 0.147),leucopenia(22.6% vs.16.6%,P = 0.208),the weekly group was more frequent than triweekly group.But there was no statistical significance.In the aspect of the grade 3-4 non-hematological toxicities,including mucosa,skin reaction and nephridium,the results were similar between two groups(P > 0.05).Subgroup analyses indicated that the 5-year DFS of weekly group was superior to triweekly group for the stage ?-?A patients(88.5% vs.74.0%,?2 = 4.991,P = 0.025).The log-rank test revealed that there were not significantly different in 5-year OS,5-year DMFS,5-year LRFS.For patients in stage ?-?,the survival outcomes were not significantly different in two groups.Conclusions: Two groups have similar incidence rate of acute toxicities.Compared with Triweekly cisplatin regimen,Weekly regimen have better outcomes,may be a preferred choice during CCRT.