ScreenIng of Genetic Susceptibility Genes for Breast Cancer Patients in CHinese communiTies

Study Overview
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Brief Summary
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This is a community-based prospective study and the research object is breast cancer patients. It is planned to take the community as the unit to inform and collect the breast cancer patients who voluntarily participate to carry out the detection of BRCA1, BRCA2, PTEN, CHEK2 and PALB2 genes through the community health service center.

Detailed Description
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This is a population-based, prospective, cohort study which has been ongoing in 3 provinces of eastern China since 2019. Up to 5000 breast cancer survivors will conduct BRCA1, BRCA2, PTEN, CHEK2, and PALB2 genetic susceptibility genes testing, fill in clinical and genetic information forms, and collect family history. Mutation rate of BRCA1/2 and other genetic susceptibility genes in Chinese community breast cancer population will be measured. Logistic regression will be performed to establish a prediction model for the probability of BRCA1/2 and other gene mutations. Kin-Cohort method will be used to calculate the penetrance of breast cancer and other common malignancies in BRCA1/2 and other genetic mutation carriers.

Official Title
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Screening of Genetic Susceptibility Genes for Breast Cancer Patients and Establishment of High-risk Populations in Chinese Communities

Conditions
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Breast Cancer, Genetic Susceptibility

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: breast cancer patients of any age; both male and female; the subjects signed the informed consent to participate in the study and abide by the study procedure before being selected. Exclusion Criteria: healthy people or other malignant tumor patients without breast cancer; unable to interview the investigator and sign the informed consent due to any reason; it is impossible to collect peripheral blood or oral mucosa samples for any reason.
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The frequency of pathogenic or likely pathogenic variants of BRCA1/2 and other genetic susceptibility genes in Chinese community breast cancer population | The frequency of pathogenic or likely pathogenic variants and 95% confidence intervals of BRCA1/2 and other genetic susceptibility genes in Chinese community breast cancer population will be measured. After stratifying according to the different clinical characteristics of the patients, chi-square tests will be use to compare the mutation rates of BRCA1/2 gene in different subgroups. | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prediction model of Genetic Susceptibility Gene (BRCA1/2 etc) mutation probability | Logistic regression will be performed to establish a prediction model for the probability of pathogenic or likely pathogenic variants of BRCA1/2 and other genes. Candidate predictors included age, race or ethnic group, the mean number of tumor in a family etc. Missing data were imputed using multiple imputation by chained equations if needed. Model validation is based on k-fold cross validation approach. Model calibration and discrimination were evaluated using HL test and AUC, respectively. ORs and corresponding 95% CI will report. | 1 year | 
| Breast cancer penetrance of Genetic Susceptibility Gene (BRCA1/2 etc) carriers | Kin-Cohort method will be used to calculate the penetrance of breast cancer and other common malignancies in BRCA1/2 and other genetic mutation carriers. | 1 year |