What is the role and significance of genetic testing in cancer treatment?

In general, genetic testing plays several important roles in cancer treatment, including reducing mortality, enabling preventive measures, inhibiting cancer cell spread, guiding treatment selection, and assessing cancer status. Its significance lies in helping determine whether targeted drugs are available after a cancer diagnosis, assisting in cancer detection, identifying genetic mutations, preparing for targeted therapy, and indicating tumor aggressiveness. A detailed analysis is as follows:

I. Roles of Genetic Testing

1. Reducing Mortality
The development of malignant tumors has now reached the molecular level. Relevant genetic testing allows for more accurate prognosis evaluation and enables more effective treatment strategies.

2. Enabling Preventive Measures
Genetic testing can assess whether patients have hereditary risk factors. For those with such factors, family members can undergo appropriate screening, allowing early detection and treatment, which leads to better outcomes.

3. Inhibiting Cancer Cell Spread
By selecting appropriate targeted drugs, genetic testing helps extend patient survival and can also suppress the spread of cancer cells.

4. Guiding Treatment Selection
Tumor genetic testing can help determine the stage and progression of the disease, thereby enabling the selection of targeted treatment strategies.

5. Assessing Cancer Status
Through blood tests, DNA in the blood of cancer patients can be analyzed to evaluate the presence and status of cancer-related genes.

II. Significance of Genetic Testing

1. Determining Availability of Targeted Therapies
Experts can match patients with suitable targeted drugs based on detected tumor gene alterations, improving treatment efficacy and long-term survival. Genetic test results also provide valuable guidance for immunotherapy, targeted therapy, and chemotherapy.

2. Assisting in Cancer Diagnosis
Circulating tumor DNA (ctDNA) testing in peripheral blood enables dynamic monitoring of treatment response and can detect signs of recurrence or metastasis 2–3 months earlier than CT or MRI scans.

3. Detecting Genetic Mutations
As cancer progresses, tumors may develop different genetic alterations compared to the original tumor. Repeat genetic testing may reveal new actionable mutations, guiding further effective treatments.

4. Preparing for Targeted Therapy
Most cancers are caused by genetic mutations. Identifying these mutations through genetic testing allows clinicians to select appropriate targeted drugs, which can extend survival in patients with advanced-stage cancer.

5. Indicating Tumor Aggressiveness
In some cancer patients, the presence of gene mutations such as KRAS, BRAF V600E, or P53 typically indicates a higher degree of malignancy and is often associated with a poorer prognosis.

Patients are advised to seek timely medical attention when experiencing symptoms and to receive standardized treatment under the guidance of healthcare professionals, which supports better recovery outcomes.