5 Effective Treatments for Triple-Negative Breast Cancer and Their Common Side Effects

Understanding TNBC
Triple-negative breast cancer (TNBC) is an aggressive form of breast cancer, requiring robust treatment approaches. The term „triple-negative” signifies that the cancer cells lack three common proteins: estrogen receptors (ER), progesterone receptors (PR), and HER2.

TNBC affects approximately 200,000 people globally each year, accounting for 10–15% of all breast cancer cases. It is more prevalent among women under 40, and those of Black or Hispanic descent.

What Is Triple-Negative Breast Cancer?

Breast cancer classifications consider the cell origin and whether the cancer is invasive (spreading to other areas). TNBC belongs to the molecular subtype classification, which identifies the presence or absence of specific proteins on or within cancer cells:

• ER and PR: Hormone receptors that bind hormones like estrogen or progesterone, fueling cancer growth.
• HER2: A receptor that promotes growth when overexpressed.

Unlike other types of breast cancer, TNBC cells do not rely on these proteins for growth, making them unresponsive to therapies targeting ER, PR, or HER2.

Treatment Options for TNBC

TNBC treatment involves a combination of chemotherapy, surgery, radiation, and sometimes targeted or immunotherapy. The approach varies based on disease stage and recurrence.

1. Chemotherapy
   • Neoadjuvant therapy: Administered before surgery to shrink tumors.
   • Adjuvant therapy: Used post-surgery to eliminate residual cancer cells.
     Common chemotherapy drugs include platinum-based agents (cisplatin, carboplatin), taxanes (docetaxel, paclitaxel), and anthracyclines.
2. Targeted Therapy and Immunotherapy
   • PARP inhibitors: Effective for people with BRCA mutations (e.g., talazoparib, olaparib).
   • PD-L1 inhibitors: Immunotherapy drugs like pembrolizumab (Keytruda) are suitable for certain advanced TNBC cases.
   • Antibody-drug conjugates: Sacituzumab govitecan-hziy (Trodelvy) is an option for metastatic TNBC.
3. Surgery
   • Lumpectomy: Removes the tumor and surrounding tissue for localized cancer.
   • Mastectomy: Complete removal of breast tissue for larger or more extensive tumors.
     Lymph node removal, through sentinel lymph node biopsy or axillary lymph node dissection, may also be necessary.
4. Radiation Therapy
   Radiation is often used post-surgery to kill remaining cancer cells. It can be particularly effective in patients with BRCA1 mutations, as these cells are less capable of repair.
5. Clinical Trials
   Research continues to explore novel drugs targeting TNBC-specific gene mutations, offering patients additional treatment avenues through clinical trials.

Common Treatment Side Effects

Treatment side effects vary based on the therapies used:

• Chemotherapy: Nausea, hair loss, fatigue, and cognitive challenges.
• Radiation: Skin changes resembling sunburn.
• Surgery: Potential lymphedema from lymph node removal.
• Targeted/Immunotherapy: Drug-specific side effects.

Discuss side effects with your healthcare provider for tailored management strategies.

TNBC Prognosis

TNBC typically has a poorer prognosis due to its aggressive nature. However, survival rates depend on the cancer stage at diagnosis:

• Localized TNBC: 91% five-year survival rate.
• Regionally spread TNBC: 66% five-year survival rate.
• Metastatic TNBC: 12% five-year survival rate.

Survival rates have improved with advancements in treatment, and individual outcomes depend on factors such as age, health status, tumor grade, and lymph node involvement.

Moving Forward

For personalized information about TNBC prognosis and treatment options, consult your healthcare team. They can provide insight into how individual factors influence your outlook and guide you through your journey.