In recent years, genetic testing has gradually become more and more well-known, and genetic testing is recommended for people with high risk of tumors during physical examinations, and doctors sometimes require genetic testing for patients with tumors.
The price is more expensive than ordinary examinations, not to mention that medical insurance is not reimbursed, so many people think that tumor genetic testing is a waste of money, which has no meaning at all. Is this really the case?
What is tumor genetic testing?
Genetic testing refers to a method of detecting the DNA molecular information in the cells of the person being tested by a specific device, analyzing the gene type and gene defects contained in them and whether their expression function is normal, so as to make a technology for disease screening, diagnosis, recurrence monitoring, targeted drug guidance, etc. [1].
Why do tumor genetic testing?
Tumor patients
Directs the use of targeted drugs
The efficacy of targeted drugs is closely related to the state of gene mutations, and before using targeted drugs, it is necessary to screen for effective mutation targets through genetic testing to "drug on the cause" to improve the treatment effect.
For example, epidermal growth factor receptor and anaplastic lymphoma kinase fusion mutations in non-small cell lung cancer may suggest that EGFR-targeted drugs (osimatinib, ametinib) and ALK inhibitors (crotinib, aletinib) are effective, respectively, while breast cancer HER2 gene amplification or overexpression suggests that patients can benefit from trastuzumab, paltuzumab, and TD-M1 therapy.
Predict the effect of treatment
Genetic testing can cover gene loci related to targeted therapy, immunotherapy, endocrine therapy, certain chemotherapy, etc., suggesting the effectiveness and toxic side effects of treatment options, and helping patients choose drugs more rationally.
Assess the risk of recurrence in patients with tumors
Some genetic tests, such as the 21 gene, can predict the risk of long-term recurrence in breast cancer patients.
People at high risk of tumors
Tumor genetic susceptibility genes were discovered
Defective or mutated genes can be detected in advance, targeted tumor prevention, greatly reducing the risk of cancer, and even avoiding tumorigenesis through intervention.
The famous movie star Angelina Jolie was detected with a hereditary BRCA1 gene mutation and underwent a preventive total resection of the breast to reduce the risk of cancer.
Early screening of tumors
Genetic testing can not only achieve early screening of high-risk groups, but also make up for the shortcomings of traditional screening (tissue biopsy) in terms of invasiveness, operability and recurrence, which can advance the early diagnosis of tumors to the stage of cell carcinogenesis and provide genetic guidance for tumor prevention.
For example, genetic testing for colorectal cancer, high-risk people can be spared from gastrointestinal endoscopy, and genetic testing through genetic material in the feces alone can determine the possible risk index of colorectal cancer at an early stage.
Who needs genetic testing?
tumor
patient
Pre-targeted therapy and immunotherapy
After drug resistance, a targeted drug or immunotherapy is required
Monitor for tiny residual lesions
Predict recurrence
Immediate family members have known harmful mutations (e.g., brCA1/2 gene)
Many people in the family develop the same cancer
Disorders associated with hereditary cancers found during physical examination (e.g., familial adenoma polyposis)
Risk
crowd
Do patients need a second test after treatment?
Some patients undergo treatment for a period of time after the first genetic test, and sometimes doctors may recommend a second genetic test.
The reason is that the genes of the tumor tissue may mutate, and the mutation is irregular, in the case of drug resistance, disease progression, it is necessary to conduct genetic testing to find out whether there is a new genetic mutation, and then take the corresponding treatment method.
bibliography
Shanghai Medical Association. Cracking the genetic code of disease[M]. Shanghai: Shanghai Science and Technology Education Press, 2018: 52