Efficacy And Toxicity Of Radiotherapy Combined With Nimotuzumab Versus Chemoradiotherapy In Locally Recurrent Nasopharyngeal Carcinoma

ObjectiveThe optimal treatment mode for locally recurrent nasopharyngeal carcinoma(LR-NPC)remained unclear.This study explored the efficacy and toxicity of nimotuzumab combined with intensity modulated radiation therapy(IMRT)in the LR-NPC.MethodsThis study retrospectively analyzed patients with LR-NPC who received IMRT treatment from January 2015 to December 2018.The treatment included radiotherapy combined with nimotuzumab once a week for 8 weeks and platinum-based(cisplatin or nedaplatin)induction chemotherapy and/or concurrent chemotherapy.Induction chemotherapy included GP(gemcitabine+platinum),TP(paclitaxel+platinum),PF(platinum+5-fluorouracil),and TPF(docetaxel+platinum+5-fluorouracil),and concurrent chemotherapy was cisplatin.Induction chemotherapy was 2-4 cycles,and concurrent chemotherapy was 2 cycles.ResultA total of 87 patients with LR-NPC were included in this analysis.32 patients received nimotuzumab combined with radiotherapy alone were divided into nimotuzumab group(N group),55 patients received chemotherapy combined with radiotherapy were divided into chemoradiotherapy group(CRT group).The median follow-up time was 47.8 months.The 4-year overall survival(OS)between N group versus CRT group were 37.1%vs 40.7%(P=0.735),and the 4-year progression-free survival(PFS)were 20.0%vs 28.6%(P=0.713).Multivariate analysis showed that age≥50 and r T3-4 staging were independent prognostic factors for OS,GTV-T volume≥30 cm~3 was independent prognostic factor for PFS,and EB virus DNA positive following radiotherapy was independent prognostic factor for distant metastasis-free survival(DMFS).All patients completed the planned treatment.Slight to moderate acute complications were common during the radiation period and mainly included mucositis and xerostomia.The majority of the acute toxic reactions were tolerated well.A total of 48 patients(55.2%)demonstrated late radiation injuries of grade≥3,including12 patients(37.5%)in the N group and 36 patients(66.5%)in the CRT group.The CRT group exhibited significantly higher incidence of severe late radiation injuries compared with that of the N group(P=0.011).Logistic regression showed that the risk of grade≥3late complications in CRT group was 4.49 times higher than that in N group(P=0.003),and the risk of grade≥3 late complications in r T3-4 group was 9.06 times higher than that in r T1-2 group(P=0.003).ConclusionThis study showed that radiotherapy combined with nimotuzumab did not appear to enhance treatment efficacy compared with chemoradiotherapy in patients with LR-NPC.However,radiotherapy combined with nimotuzumab may be superior to chemoradiotherapy due to its lower incidence of acute and late toxicities.Further studies are required to confirm the current findings.