Purpose: Molecular residual disease (MRD) is a promising biomarker in colorectal cancer (CRC) for prognosis and guiding treatment, while the whole-exome sequencing (WES) based tumor-informed assay is standard for evaluating MRD based on circulating tumor DNA (ctDNA). In this study, we assessed the feasibility of a fixed-panel for evaluating MRD in CRC. Materials and Methods: Seventy-five patients with resectable stage I-III CRC were enrolled. Tumor tissues obtained by surgery, and preoperative and postoperative day 7 blood samples were collected. The ctDNA was evaluated using the tumor-agnostic and tumor-informed fixed assays, as well as the WES-based and panel-based personalized assays in randomly selected patients. Results: The tumor-informed fixed assay had a higher preoperative positive rate than the tumor-agnostic assay (73.3% vs. 57.3%). The preoperative ctDNA status failed to predict disease-free survival (DFS) in either of the fixed assays, while the tumor-informed fixed assay-determined postoperative ctDNA positivity was significantly associated with worse DFS (hazard ratio [HR], 20.74; 95% confidence interval [CI], 7.19 to 59.83; p < 0.001), which was an independent predictor by multivariable analysis (HR, 28.57; 95% CI, 7.10 to 114.9; p < 0.001). Sub-cohort analysis indicated the WES-based personalized assay had the highest preoperative positive rate (95.1%). The two personalized assays and the tumor-informed fixed assay demonstrated same results in postoperative landmark (HR, 26.34; 95% CI, 6.01 to 115.57; p < 0.001), outperforming the tumor-agnostic fixed panel (HR, 3.04; 95% CI, 0.94 to 9.89; p=0.052). Conclusion Our study confirmed the prognostic value of the ctDNA positivity at postoperative day 7 by the tumor-informed fixed panel. The tumor-informed fixed panel may be a cost-effective method to evaluate MRD, which warrants further studies in future.

Purpose: Molecular residual disease (MRD) is a promising biomarker in colorectal cancer (CRC) for prognosis and guiding treatment, while the whole-exome sequencing (WES) based tumor-informed assay is standard for evaluating MRD based on circulating tumor DNA (ctDNA). In this study, we assessed the feasibility of a fixed-panel for evaluating MRD in CRC. Materials and Methods: Seventy-five patients with resectable stage I-III CRC were enrolled. Tumor tissues obtained by surgery, and preoperative and postoperative day 7 blood samples were collected. The ctDNA was evaluated using the tumor-agnostic and tumor-informed fixed assays, as well as the WES-based and panel-based personalized assays in randomly selected patients. Results: The tumor-informed fixed assay had a higher preoperative positive rate than the tumor-agnostic assay (73.3% vs. 57.3%). The preoperative ctDNA status failed to predict disease-free survival (DFS) in either of the fixed assays, while the tumor-informed fixed assay-determined postoperative ctDNA positivity was significantly associated with worse DFS (hazard ratio [HR], 20.74; 95% confidence interval [CI], 7.19 to 59.83; p < 0.001), which was an independent predictor by multivariable analysis (HR, 28.57; 95% CI, 7.10 to 114.9; p < 0.001). Sub-cohort analysis indicated the WES-based personalized assay had the highest preoperative positive rate (95.1%). The two personalized assays and the tumor-informed fixed assay demonstrated same results in postoperative landmark (HR, 26.34; 95% CI, 6.01 to 115.57; p < 0.001), outperforming the tumor-agnostic fixed panel (HR, 3.04; 95% CI, 0.94 to 9.89; p=0.052). Conclusion Our study confirmed the prognostic value of the ctDNA positivity at postoperative day 7 by the tumor-informed fixed panel. The tumor-informed fixed panel may be a cost-effective method to evaluate MRD, which warrants further studies in future.

Purpose: Molecular residual disease (MRD) is a promising biomarker in colorectal cancer (CRC) for prognosis and guiding treatment, while the whole-exome sequencing (WES) based tumor-informed assay is standard for evaluating MRD based on circulating tumor DNA (ctDNA). In this study, we assessed the feasibility of a fixed-panel for evaluating MRD in CRC. Materials and Methods: Seventy-five patients with resectable stage I-III CRC were enrolled. Tumor tissues obtained by surgery, and preoperative and postoperative day 7 blood samples were collected. The ctDNA was evaluated using the tumor-agnostic and tumor-informed fixed assays, as well as the WES-based and panel-based personalized assays in randomly selected patients. Results: The tumor-informed fixed assay had a higher preoperative positive rate than the tumor-agnostic assay (73.3% vs. 57.3%). The preoperative ctDNA status failed to predict disease-free survival (DFS) in either of the fixed assays, while the tumor-informed fixed assay-determined postoperative ctDNA positivity was significantly associated with worse DFS (hazard ratio [HR], 20.74; 95% confidence interval [CI], 7.19 to 59.83; p < 0.001), which was an independent predictor by multivariable analysis (HR, 28.57; 95% CI, 7.10 to 114.9; p < 0.001). Sub-cohort analysis indicated the WES-based personalized assay had the highest preoperative positive rate (95.1%). The two personalized assays and the tumor-informed fixed assay demonstrated same results in postoperative landmark (HR, 26.34; 95% CI, 6.01 to 115.57; p < 0.001), outperforming the tumor-agnostic fixed panel (HR, 3.04; 95% CI, 0.94 to 9.89; p=0.052). Conclusion Our study confirmed the prognostic value of the ctDNA positivity at postoperative day 7 by the tumor-informed fixed panel. The tumor-informed fixed panel may be a cost-effective method to evaluate MRD, which warrants further studies in future.

Purpose: Molecular residual disease (MRD) is a promising biomarker in colorectal cancer (CRC) for prognosis and guiding treatment, while the whole-exome sequencing (WES) based tumor-informed assay is standard for evaluating MRD based on circulating tumor DNA (ctDNA). In this study, we assessed the feasibility of a fixed-panel for evaluating MRD in CRC. Materials and Methods: Seventy-five patients with resectable stage I-III CRC were enrolled. Tumor tissues obtained by surgery, and preoperative and postoperative day 7 blood samples were collected. The ctDNA was evaluated using the tumor-agnostic and tumor-informed fixed assays, as well as the WES-based and panel-based personalized assays in randomly selected patients. Results: The tumor-informed fixed assay had a higher preoperative positive rate than the tumor-agnostic assay (73.3% vs. 57.3%). The preoperative ctDNA status failed to predict disease-free survival (DFS) in either of the fixed assays, while the tumor-informed fixed assay-determined postoperative ctDNA positivity was significantly associated with worse DFS (hazard ratio [HR], 20.74; 95% confidence interval [CI], 7.19 to 59.83; p < 0.001), which was an independent predictor by multivariable analysis (HR, 28.57; 95% CI, 7.10 to 114.9; p < 0.001). Sub-cohort analysis indicated the WES-based personalized assay had the highest preoperative positive rate (95.1%). The two personalized assays and the tumor-informed fixed assay demonstrated same results in postoperative landmark (HR, 26.34; 95% CI, 6.01 to 115.57; p < 0.001), outperforming the tumor-agnostic fixed panel (HR, 3.04; 95% CI, 0.94 to 9.89; p=0.052). Conclusion Our study confirmed the prognostic value of the ctDNA positivity at postoperative day 7 by the tumor-informed fixed panel. The tumor-informed fixed panel may be a cost-effective method to evaluate MRD, which warrants further studies in future.

Objective Using healthy female reproductive-age rhesus macaques as the research subjects,we explored the correlation between menstrual cycle abnormalities and gut microbiota composition by using 16S rRNA metagenomic sequencing.Methods Twenty-seven healthy female rhesus macaques were divided into regular menstrual and irregular menstrual groups.Fecal samples were collected at follicular phase(FP),ovulation phase(OP)and luteal phase(LP)of the two groups.The structure and diversity of bacterial flora in different physiological periods were analyzed and compared between the two groups.Results At the phylum level,Firmicutes,Bacteroidetes,and Proteobacteria dominated the sample flora in the follicular,luteal,and ovulatory phases of the rhesus macaques in both the regular and irregular groups,with a combined percentage of more than 98% .At the genus level,the genus Prevotella_9,Ruminococcaceae_UCG-002,Lactobacillus,Prevotella_2,Phascolarctobacterium,Ruminococcaceae_UCG-005,Streptococcus,Blautia,Prevotellaceae_NK3B31_group,Rikenellaceae_RC9_gut_group were dominant.In the luteal phase the percentage of Firmicutes was higher in the regular group than in the irregular group,while the opposite was true for Bacteroidetes.Spirochaetes were higher in the regular group than in the irregular group at all 3 stages(P＜0.05).Conclusion There were some differences in intestinal microbial composition between the two groups of macaques with regular and irregular menstrual cycles,which provided some reference for the study of intestinal bacteria and ovulation disorders.