International Journal of Clinical Research

Objective To analyze the dynamic changes of the microbiome in multiple sites before and after radiotherapy in patients with cervical cancer and their association with therapeutic effects. Methods From January 2024 to July 2024, 36 newly diagnosed patients were included. Tumor tissue, vaginal, urethral, fecal and oral saliva samples were collected before radiotherapy (T0) and at the end of radiotherapy (T1) respectively, and 16S rRNA V3-V4 region sequencing was performed. The therapeutic effect was evaluated according to the RECIST 1.1 standard, and the relationship between microbiota characteristics and objective response rate (ORR) was explored by combining α/β diversity and Spearman analysis. Results Radiotherapy significantly altered the structure of the microbiota within the tumor and in the oral cavity. Among them, Proteobacteria in the tumor increased, Bacteroidetes decreased, and Epsilonbacteraeota in the oral cavity increased. The amplitudes of all three changes were positively correlated with ORR (P<0.05). Conclusion The response of the tumor microenvironment and oral microbiota is site-specific, which could be used as a potential biomarker for predicting the efficacy of radiotherapy.

Cervical cancer; External beam radiation therapy; Microbiome; Multiple sites; Therapeutic effect prediction