盆腔肿瘤患者放疗后肠道菌群变化的研究

Alteration of intestinal flora after radiotherapy in patients with pelvic cancer

目的观察盆腔肿瘤患者放疗后肠道菌群的变化,探讨放射性肠炎与肠道菌群的相关性及益生菌干预对肠道菌群及腹泻的影响。方法选取2018年3月至11月南京医科大学附属苏州医院确诊的盆腔肿瘤患者22例,包括直肠癌5例、子宫颈癌15例及子宫内膜癌2例,子宫颈癌患者中5例在放疗同时使用益生菌干预。选取同期健康体检者10名作为对照组。患者放疗前后各收集一次粪便标本,运用16SrDNA检测粪便菌群,分析放疗对肠道菌群的影响。结果健康对照组粪便标本中主要菌门为厚壁菌门(39.86%)、拟杆菌门(37.77%)、分类不明确菌门(15.96%)、变形菌门(5.03%),盆腔肿瘤患者粪便标本中主要菌门与健康对照组一致,但在丰度上有所区别。患者肠道菌群放疗前后存在差异,放疗后患者肠道菌群多样性、丰度下降,且腹泻严重患者下降幅度大。放疗后患者肠道菌群厚壁菌门/拟杆菌门丰度比下降。腹泻严重患者志贺菌属及梭杆菌属丰度在放疗后上升。口服益生菌可维持患者肠道菌群多样性和丰度稳定,减轻腹泻症状。结论盆腔肿瘤患者放疗后肠道菌群多样性、丰度下降,尤其是腹泻严重患者,口服益生菌可减轻腹泻症状。

Objective To investigate the effect of pelvic radiotherapy on intestinal flora,the correlation between radiation enteritis and intestinal flora,and the effect of probiotics intervention on intestinal flora and diarrhea.Methods From March to November 2018,a total of 22 patients who were admitted to the Affiliated Suzhou Hospital of Nanjing Medical University were enrolled in the study,including 5 patients with colorectal cancer,15 patients with cervical cancer and 2 patients with endometrial carcinoma.Five patients with cervical cancer received oral administration of probiotics combined with radiotherapy.Ten healthy physical examiners were selected as the control group.The stool samples were collected from each patient before and after radiotherapy,and 16S rDNA sequencing technology was used to detect the fecal flora and analyze the effect of radiotherapy on intestinal flora.Results The main composition of intestinal flora in the stool samples of healthy control group was Firmicutes(39.86%),Bacteroidetes(37.77%),unclassified bacteria(15.96%)and Proteobacteria(5.03%),which was similar to patients,but the abundance of bacteria was significantly different.There were differences in the intestinal flora of patients before and after radiotherapy.Microbial diversity and abundance were altered after radiotherapy,especially in patients who later developed severe diarrhea.The Firmicutes/Bacteroidetes ratio was altered after radiotherapy.The abundance of Escherichia-Shigella and Fusobacterium increased after radiotherapy in patients who developed severe diarrhea.Oral administration of probiotics could alleviate the diarrhea and reduce the decline of microbial diversity and abundance.Conclusions In patients with pelvic tumors,the diversity and abundance of intestinal flora decrease after radiotherapy,especially in patients with severe diarrhea.Oral probiotics can alleviate the diarrhea.