The Survival Impact Of The Interval Between The Induction Of Chemotherapy And Radiotherapy And Neutropenia During The First Cycle Of Induction Chemotherapy In Locoregionally Advanced Nasopharyngeal Carcinom

Part I:The impact of the interval between the induction of chemotherapy and radiotherapy on the survival of patients with nasopharyngeal carcinomaBackground:There have been no reliable scientific studies examining whether the interval between induction chemotherapy(IC)to initiating radiotherapy is associated with poor outcomes of nasopharyngeal carcinoma(NPC).Methods:In this retrospective study,we included a total 239 local advanced NPC patients who underwent concurrent chemoradiotherapy and induction chemotherapy.Based on the interval between induction chemotherapy and IMRT,the patients were classified into three groups:Group A(?7 vs.>7 days),Group B(?14 vs.>14 days),and Group C(?21 vs.>21 days).Univariate and multivariate regression analyses were performed to determine the prognostic factors of survival outcomes.Results:The median IC-IMRT interval was 9 days(range,1?76 days).The median follow-up time was 40 months(range,4-58 months).The IC-IMRT interval including Group A,Group B and Group C was not significantly associated with OS,DMFS,LRFS,or DFS.Multivariate analysis showed that the tumor stage was the independent significant predictor for OS,DMFS,LRFS and DFS.Conclusion:Our study showed that the interval up to three weeks between IC and the radiotherapy did not lead to a worse prognosis among NPC.Part ?:Neutropenia during the First Cycle of Induction Chemotherapy Is Prognostic for Poor Survival in Locoregionally Advanced Nasopharyngeal CarcinomaPurposeThe purpose of this study was to investigate the effect of neutropenia during the first cycle of induction chemotherapy(IC-1)on survival in locoregionally advanced nasopharyngeal carcinoma(LANPC).Materials and MethodsEligible patients(n=545)with LANPC receiving IC+concurrent chemoradiotherapy were included.Based on nadir neutrophil after IC-1,all patients were categornzed into three groups:no/grade 1-2/grade 3-4 neutropenia.Five-year overall survival(OS)and disease-free survival(DFS)were compared between groups and subgroups stratified by IC regimen.We also explored the occurrence of IC-1-induced myelosuppression events and the minimal value of post-treatment neutrophil-to-lymphocyte ratio(post-NLRmin).Univariate/multivariate analy ses were performed to investigate the effect of IC-1-induced neutropenia,timing of neutropenia,number of myelosuppression events,and high post-NLRmin on OS/DFS.ResultsGrade 1?2/grade 3-4 neutropenia were associated with poorer OS/DFS than no neutropenia(all p<0.05);OS/DFS were not significantly different between patients experiencing grade 1-2 vs.3-4 neutropenia.Neutropenia had no significant effect on OS/DFS in patients receiving docetaxel-cisplatin-5-fluorouracil(TPF).Grade 1-2(grade 3-4)neutropenia negatively influenced OS/DFS in patients receiving cisplatin-5-fluorouracil(PF)(PF and docetaxel-cisplatin[TP];all p<0.05).Neutropenia,two/three myelosuppression events,and high post-NLRmin(? 1.33)was most frequent on days 5-10,second and third week of IC-1 respectively.After adjustment for covariates,IC-1-induced neutropenia,two/three myelosuppression events,and post-NLRmin)1.33 were validated as negative predictors of OS/DFS(all p<0.05);timing of neutropenia had no significant effect.ConclusionOccurrence of neutropenia,number of myelosuppression events,and high post-NLRmin during PF/TP IC-1 have prognostic value for poor survival in LANPC.