Genetic analyses of breast cancer (MAMMAPRINT)
Genetic testing for breast cancer is the most modern and reliable prognostic tool for cancer biological aggressiveness. Tests are performed on tumor tissue surgically removed from the body.
One of the genetic tests for breast cancer available in Serbia is MammaPrint. It processes 150 genes in tumor tissue and, based on their mapping, gives an estimate of the risk of disease progression on a scale of 0.001 to 1.00. These data are combined with standard prognostic parameters (disease stage, histological type of tumor, histological and nuclear grade, estrogen and progesterone receptors, Her2 receptors, Ki 67…) to obtain a more complete and precise picture of the degree of probability that cancer will develop in the future.
The reliability of MammaPrint has been proven by the MINDACT trial, a famous scientific study with the highest level of clinical evidence.
The reliability of MammaPrint has been proven by the MINDACT trial, a famous scientific study with the highest level of clinical evidence. This study showed that as many as 46% of breast cancer patients unnecessarily receive toxic chemotherapy after surgery. This happens because patients are prescribed chemotherapy based on the disease stage, without complete insight into the tumor’s biological aggressiveness.
For example, a patient who had surgery due to 4cm breast cancer, with positive estrogen and progesterone receptors and no metastases in the axillary lymph nodes, will receive chemotherapy after surgery because the tumor is large, according to classical protocols. However, if MammaPrint shows that it is low-risk cancer, chemotherapy can be avoided as it does not improve the already good prognosis of the disease at all. The only treatment after surgery will be hormone therapy, which is non-toxic and well tolerated.
Avoiding unnecessary chemotherapy is the most significant benefit of breast cancer genetic analysis.
Avoiding unnecessary chemotherapy is the most significant benefit of breast cancer genetic analysis. The toxic effects of chemotherapy are somewhat obscured by the severeness of the disease being treated, but we should not forget that chemotherapy has significant negative consequences for the patient’s health, psychological status, and social functioning: hair loss, damage to the bone marrow, heart and brain, unpleasant stigmatization, being absent from work… All these consequences can be avoided when it comes to types of cancer that respond well to chemotherapy, which can often be even completely cured with chemotherapy (Her2 positive, triple-negative tumors…). So, when its therapeutic effects are negligible, it is vital for the patient that chemotherapy is avoided.
Another benefit of genetic analysis is the positive psychological effect on the patient when learning that their tumor is low-risk cancer.
MammaPrint analyses are recommended for patients who, based on the disease stage, belong to the group of patients who will be recommended chemotherapy, but based on standard immunohistochemical analyses, it can be assumed that it is a cancer of low biological aggressiveness (positive estrogen and progesterone receptors, Her2 negative tumors, low Ki 67…).