Breast and ovarian cancer risk (determination of BRCA1(4) and BRCA2(4) gene mutations by PCR)

Malignant tumors (cancer) of the breast and ovaries are the most common forms of malignant tumors among women of the Republic of Kazakhstan.

So in 2020, breast cancer was in the first place in Kazakhstan in terms of morbidity. This type of tumor also occupies the first positions in Europe, the USA, and Asia.

According to the results of analysis conducted by the National Cancer Institute (USA), breast cancer will develop in about 13% of women in the general population, whereas the risk of developing breast cancer among women with a mutation in the BRCA1 gene is 55%-72%, and in the BRCA2 gene is 45%-69%.

As for ovarian cancer, it is also one of the five most common malignant tumors among women in Kazakhstan. Scientists say that according to preliminary estimates, about 1.2% of women will experience this disease during their lifetime. And if women have a BRCA1 gene mutation, the risk increases to 39-44%, and to 11-17% in the presence of a mutation in the BRCA2 gene.

In addition, women with mutations in these genes develop cancer at a younger age than women with unchanged BRCA1 and BRCA2 genes.

BRCA1 (BReast CAncer 1 gene) and BRCA2 (BReast CAncer 2 gene) are genes that produce proteins that help repair damaged DNA, so if they have mutations, the main mechanism for repairing DNA damage is disrupted. Cells that do not have functioning BRCA1 or BRCA2 proteins can get out of control and become cancerous.

Early diagnosis of breast cancer is an important problem of modern oncogenetics due to the significant frequency of detection of tumors in the late stages.

Most clinical cases of hereditary cancer are associated with mutations in these genes. It was found that the survival rate of patients with hereditary cancer of the female reproductive system is significantly higher than in the general group of patients, regardless of the stage and treatment: the 5-year survival rate of patients with hereditary breast cancer is 58.9±6.3%, while in sporadic cancer it is 39.7±4.6%.

Also, information about the status of BRCA genes is used as a predictive marker during chemotherapy.

The status of genes can be determined by DNA isolated from blood.

Indications:

diagnosis of hereditary forms of breast cancer and ovarian cancer in healthy women,
additional examination of women with a confirmed diagnosis of breast cancer and ovarian cancer to determine treatment tactics and predict the response to treatment.
women with a confirmed diagnosis of breast cancer in combination with ovarian cancer or pancreatic cancer,
men with a confirmed diagnosis of breast cancer in men;
In women with confirmed breast cancer aged < 60 years with triple-negative breast cancer;
all patients with ovarian cancer.

Interpretation of the results:

Positive result A positive test result means that a woman has a mutation in one of the BRCA1/BRCA2 genes and has a higher risk of developing breast cancer or ovarian cancer compared to women without the gene mutation. A positive result does not mean that a woman will necessarily develop cancer! Women with a mutation of these genes should definitely discuss with their attending physician further measures for examination, the frequency of examination, and consider measures to reduce the risk of developing cancer.

Negative result A negative test result means that these BRCA1/BRCA2 gene mutations have not been detected. The test result is considered "truly negative" in the absence of a specific mutation of the BRCA1/BRCA2 genes that were previously detected in a relative. A negative test result does not mean that it does not exclude the possibility of developing breast or ovarian cancer in the future; it indicates that the risk is general.