The Changes Of Oral Microflora In Patients Receiving Chronoradiotherapy For Head And Neck Cancer

This research aimed to explore the advantages of chronoradiotherapy from theperspective of radiotherapy-induced oral mucositis(RIOM) and oral microflorachanges in patients with head and neck cancer, and provide theoretical basis for theclinical popularization and application.Purposes:1. To investigate the incidence and severity of RIOM in head and neck cancerpatients receiving chronoradiotherapy, and explore the differences betweenchronoradiotherapy and conventional time radiotherapy.2. To investigate the changes of oral microflora in patients receivingchronoradiotherapy for head and neck cancer, observe the differences betweenchronoradiotherapy and conventional time radiotherapy, and explore thepotential advantages of chronoradiotherapy, provide the possible theoreticalbasis for clinical popularization and application.Methods:1. Select60patients(33males and27females,aged from28to64years) with headand neck cancer, randomly divided into two groups,chronoradiotherapy groupand conventional group,30cases each. Respectively receiving radiation at fixedtime as during19:00and21:00in the evening and from7:00to9:00in themorning.2. Saliva was sampled from head and neck cancer patients before and afterradiation(When the total absorbed dose reached up to30~50Gy) for oralmicroflora cultivation, isolation and identification, then calculated the colonyforming units(CFU).3. The differences between the two groups in terms of severity of RIOM, bacteriadetection rate,detection amount and constituent ratio were analyzed with SPSS17.0software package.Results: 1. After radiotherapy, the incidence of RIOM was90.0%(27/30) and93.3%(28/30)respectively for chronoradiotherapy and chronoradiotherapy group,it had nosignificant differences(P>0.05);According to the severity of RIOM, it was foundthat the severity of RIOM in chronoradiotherapy group was relatively less severethan conventional group,and it had statistically significant differences (P<0.05).2. When compared the severity of RIOM between different sexes, it was found thatwomen were more severe than men in chronoradiotherapy group(P<0.05).Whilein conventional group, there was no statistically significant difference betweenmen and women (P>0.05).Between the two groups, compared with the same sex,the severity of RIOM of men in chronoradiotherapy group were less severe thanconventional group(P<0.05), that of women had no statistically significant(P>0.05).3. When compared after with before radiotherapy,for the two groups,it was foundthat detection rate of oral candida and streptococcus both significantly increasedafter radiotherapy(P<0.05),that of actinomycetes, neisseria and lactobacilluswere detected to have no statistically significant differences(P>0.05); Detectionamount of oral candida and streptococcus both significantly increased afterradiotherapy for the two groups(P<0.05), that of actinomycetes and neisseriaboth decreased (P<0.05);Detection amount of lactobacillus after radiation inconventional group significantly increased(P<0.05),that of chronoradiotherapygroup had no obvious differences(P>0.05);In chronoradiotherapy group,constitution ratio of actinomycetes decreased after radiation (P<0.05),oralcandida,streptococcus,neisseria and lactobacillus were detected to have nostatistically significant differences(P>0.05);In conventional group,oral candidaand streptococcus constitution ratio was found increased significantly afterradiotherapy(P<0.05),that of neisseria reduced significantly (P<0.05),that ofactinomycetes and lactobacillus both had no obvious differences(P>0.05).4. After radiotherapy,between the two groups,the bacterial detection rate,detectionamount and constituent ratio of oral candida,streptococcus,actinomycetes,neisseria,lactobacillus all had no statistically significant differences(P>0.05). Conclusions:1. The severity of RIOM in chronoradiotherapy group was less severe than those inconventional time group for head and neck cancer patients receiving radiation.2. Different sexes had different oral mucosal toxic reaction to chronoradiotherapy.3. Oral microeflora of patients receiving chronoradiotherapy for head and neckcancer had some changes in detection of oral candida, streptococcus,actinomycetes, neisseria.4. Chronoradiotherapy had certain advantages in oral mucosal toxic reaction andchanges of oral microflora,it deserved further study and clinical popularization.