Targeted Medications for Breast Cancer

Personalized therapies can effectively inhibit tumor growth by blocking specific mechanisms that control the growth and survival of cancer cells. They are also used in breast cancer treatment.

An Overview of Content:

• Personalized therapy for breast cancer
• Targeted approach against breast cancer
• Targeted medications for breast cancer treatment

Personalized Therapy for Breast Cancer

Targeted cancer therapies, also known as "targeted therapies," play an important role in improving the prognosis of specific groups of breast cancer patients. These therapies involve medications that specifically intervene in processes essential for tumor growth. This type of treatment is also referred to as "personalized therapy." However, the term can be misleading. It is not so much about the person affected but rather about the specific biological characteristics of their tumor. When certain features of the tissue are present, these allow for such therapies. Targeted medications are often combined with other treatment forms such as antihormonal therapies or chemotherapy to enhance the effectiveness of tumor treatment.

Benefit: Gaining Time

Targeted therapies aim to inhibit mechanisms that are crucial for tumor cells to grow and survive. They attach to specific molecules (receptors) and interrupt the transmission of information within and between cancer cells. However, tumor cells sometimes manage to "unlock" these mechanisms and find cellular bypass routes. As a result, the effectiveness of these new drugs can diminish over time. Nevertheless, patients can gain valuable time through these therapies.

Drawback: Side Effects Are Possible

Despite the modified mode of action of new cancer drugs, promising a therapy specifically aimed at the diseased cells, targeted cancer therapies also come with side effects. This is because the target structures of the active substances can also be present in healthy cells. Depending on the medication, side effects can include skin rashes, nail changes, nausea, headaches, and fatigue. The cardiovascular system, liver, and lungs may also be affected.

Targeted Approach Against Breast Cancer

To find the right targeted treatment, the tumor must be thoroughly analyzed. Tests are performed either on tumor tissue (biopsy) or blood samples. Targeted therapies are only effective if the tumor exhibits the relevant features. Whether such a therapy is suitable also depends on other factors such as disease stage, prior treatments, compatibility, comorbidities, and the patient's personal preferences. Only after considering all these individual factors can it be considered a truly personalized therapy.

Various laboratory tests can determine which targeted medications the tumor cells might respond to.

Targeted Medications for Breast Cancer Treatment

The following tumor characteristics have approved medications for breast cancer treatment:

HER2: About 15% of all breast cancer patients have a higher concentration of the HER2 growth factor receptor in the tumor tissue. HER2 inhibitors are often combined with chemotherapy or antihormonal therapy. Examples: Trastuzumab, Pertuzumab, Lapatinib

mTOR: When the mTOR signaling pathway is overactive, antihormonal therapies lose their effectiveness. Blocking this pathway makes tumor cells responsive again to antihormonal therapy. Example: Everolimus

BRCA: BRCA genes are tumor-suppressing genes involved in the constant repair of genetic material. If these genes are mutated, it can result in hereditary breast cancer, but de novo mutations can also occur without a family history. PARP inhibitors prevent tumor cells from repairing their genetic material after platinum-based chemotherapy, causing them to die. Examples: Olaparib, Talazoparib

CDK4/6: CDK4/6 inhibitors prevent the uncontrolled division of tumor cells. These are usually combined with antihormonal therapy. Examples: Palbociclib, Ribociclib, Abemaciclib

PD-1/PD-L1: PD-1/PD-L1 inhibitors activate the body’s immune system to fight cancer cells. These are also known as checkpoint inhibitors. Together with chemotherapy, they form a potent duo. Examples: Atezolizumab, Pembrolizumab

PIK3CA: Mutations in the PIK3CA gene occur in about 40% of women with hormone-sensitive metastatic breast cancer. When this gene is blocked, tumor growth slows down. The PIK3CA inhibitor is combined with an antihormonal agent. Example: Alpelisib

VEGF: VEGF is a protein that the tumor uses to create new blood vessels, which it needs to nourish itself. Antibodies can prevent this, effectively "starving" the tumor. Example: Bevacizumab