Assessment of Induction Chemotherapy Regimen TPF Versus GP Followed By Concurrent Chemoradiotherapy in Locally Advanced Nasopharyngeal Carcinoma: A Retrospective Cohort Study

Abstract

Many clinical studies have shown that induction chemotherapy followed by concurrent chemoradiotherapy improved the survival of locally advanced nasopharyngeal carcinoma (NPC). However, it is still unknown that which induction chemotherapy regimen is the optimal choice. This study focused on the comparison of efficacy and toxicities between induction chemotherapy regimen TPF and GP in locally advanced NPC. Between January 2008 and July 2015, patients with locally advanced NPC (clinical stage III-IVb) were retrospectively analyzed. Inclusion criteria were as follows: (1) pathologically confirmed NPC; (2) clinical stage III-IVb according to the 7th edition of the American Joint Committee on Cancer (AJCC) stage criteria; (3) receiving either TPF regimen plus CCRT or GP regimen plus CCRT; (4) radiotherapy was performed using intensity modulated radiation therapy (IMRT). Exclusion criteria were as follows: (1) patients receiving adjuvant chemotherapy; (2) patients with other malignant diseases. The primary endpoint was overall survival (OS). The Secondary endpoints included progression-free survival (PFS), distant metastasis-free survival (DMFS) and locoregional recurrence-free survival (LRFS). The Kaplan-Meier survival curves and log-rank test were used to evaluate the OS, PFS, LRFS, and DMFS of the two groups. Univariate and multivariate analyses were applied to identify the independent prognostic factors. Chi-square test was performed to compare the toxic effects between the two groups. A total of 80 patients treated with TPF regimen plus CCRT and 80 with GP regimen plus CCRT were eligible for this study. After a median follow-up of 47 months (range 8–97months), no differences were observed between the two groups in terms of 3-year OS (86.1% vs. 94.8%, p = 0.123), PFS (81.1% vs. 90.8%, p = 0.224), DMFS (82.3% vs. 94.1%, p = 0.087), or LRFS (93.6% vs.96.1%, p = 0.794). The results of the multivariate Cox proportional hazard analysis showed that the treatment group was not an independent prognostic factor for OS (HR 2.341; 95% CI 0.878–6.241; p = 0.089), PFS (HR 1.814; 95% CI 0.815–4.036; p=0.145), DMFS (HR 2.343; 95%CI 0.942–5.830; p = 0.067), or LRFS (HR 1.243; 95% CI 0.377–4.103; p = 0.721). Clinical stage was an independent prognostic factor affecting OS (HR 0.198; 95 %CI 0.040–0.975; p = 0.046) and PFS (HR 0.224; 95 %CI 0.062–0.810; p = 0.023).There was significant difference in III-IV hepatic toxicity between the two groups (0 vs. 18.6%, p=0.000). No significant differences were observed in bone marrow suppression and kidney dysfunction between the two arms. GP induction chemotherapy plus CCRT achieved similar survival outcomes to those with TPF induction chemotherapy for locally advanced NPC. However, GP regimen increased grade 3–4 hepatic dysfunction compared with TPF induction chemotherapy. More prospective clinical trials are needed to determine the most effective induction chemotherapy regimen for locally advanced NPC.