Induction chemotherapy plus IMRT alone versus induction chemotherapy plus IMRT-based concurrent chemoradiotherapy in locoregionally advanced nasopharyngeal carcinoma: a retrospective cohort study

To evaluate the value of concurrent chemotherapy after induction chemotherapy for locoregionally advanced nasopharyngeal carcinoma (NPC) in the era of intensity-modulated radiation therapy (IMRT), we performed this retrospective cohort study to compare the efficiency and toxicities of induction chemotherapy plus IMRT alone (IC + RT) versus induction chemotherapy plus IMRT-based concurrent chemoradiotherapy (IC + CCRT). We analyzed data from patients with locoregionally advanced NPC (stage III–IVb) who were treated at the West China hospital between January 2008 and December 2014. Patients received docetaxel, cisplatin, and 5-fluorouracil (TPF) IC followed by IMRT alone (IC + RT group) or IMRT plus cisplatin concurrent chemotherapy (IC + CCRT group). The main endpoint was overall survival (OS), which was evaluated by the Kaplan–Meier method and log-rank test. Multivariate Cox proportional hazard analysis was used to identify potential independent prognostic factors. Treatment-associated toxicities were compared between groups using the Chi squared test. A total of 78 patients treated with IC + RT and 76 with IC + CCRT were analyzed. The median follow-up time was 59 months (range: 7–108 months). There was no difference between patients treated with IC + RT and IC + CCRT in terms of 3-year OS (89.0% versus 88.0%, p = 0.286), progression-free survival (76.8% versus 80.0%, p = 0.142), locoregional recurrence-free survival (87.1% versus 90.5%, p = 0.156), or distant metastasis-free survival (83.6% versus 82.6%, p = 0.567). Treatment (IC + RT versus IC + CCRT) was not an independent prognostic factor for OS (HR 1.425, 95% CI 0.698–2.908; p = 0.331). IC + CCRT was associated with a higher incidence of grade 3–4 neutropenia than IC + RT during radiotherapy (11.8% versus 1.3%, p = 0.020). IC plus IMRT alone achieves similar patient survival outcomes as IC plus IMRT-based concurrent chemoradiotherapy, and has a lower incidence of toxicity.