Understanding Breast Cancer: Challenges, Tumour Types, and the Promise of Precision Medicine

Category : Breast | Sub Category : Breast Cancer Posted on 2025-07-09 23:04:51

Breast cancer remains the most common cancer affecting women worldwide. In 2022 alone, over 2 million new cases were diagnosed globally. Despite advancements in research and treatment, breast cancer continues to pose significant challenges due to its complexity and variability.

What Causes Tumour Development?

In healthy tissue, the processes of cell growth, division, and death are tightly regulated. However, when mutations occur in a cell’s DNA, this regulation can break down. As a result, cells may begin to multiply uncontrollably, leading to the formation of a tumour.

Tumours can be either benign (non-cancerous) or malignant (cancerous). While benign tumours remain localized and generally pose less risk, malignant tumours are more dangerous. They have the ability to invade nearby tissues and spread (metastasize) to distant organs, such as the lungs, liver, or bones.

Cancer cells possess unique capabilities that allow them to survive and proliferate. These include evading the immune system, initiating the formation of new blood vessels (angiogenesis), and adapting to harsh conditions like low oxygen levels or the presence of anti-cancer drugs.

Interestingly, only about 5% to 10% of cancers result from inherited (germline) mutations present from birth. The vast majority are linked to environmental factors, lifestyle choices, and spontaneous mutations, making many cancers potentially preventable through healthy living and regular physical activity.

Types of Breast Cancer Tumours

Breast cancer is not a single disease. It encompasses several subtypes, each with distinct biological characteristics and treatment responses. Key classifications include:

• Ductal Carcinoma In Situ (DCIS): A non-invasive form of breast cancer where abnormal cells are confined to the milk ducts and have not spread to surrounding tissue.
• Invasive Ductal Carcinoma (IDC): The most prevalent type, where cancer cells have breached the duct walls and invaded nearby breast tissue.
• Invasive Lobular Carcinoma (ILC): Begins in the milk-producing lobules and infiltrates surrounding breast tissue. Lobules differ anatomically from ducts, which transport milk to the nipple.
• Triple-Negative Breast Cancer (TNBC): Lacks estrogen receptors, progesterone receptors, and HER2 protein. This subtype tends to be more aggressive and harder to treat due to the absence of common therapeutic targets.
• HER2-Positive Breast Cancer: Characterized by overexpression of the HER2 protein, which drives rapid cancer cell growth. HER2-targeted therapies can be effective for this subtype.
• Hormone Receptor-Positive Breast Cancer: Driven by hormones such as estrogen or progesterone. Hormone-blocking therapies are often effective for managing this form of cancer.

Why Is Breast Cancer Difficult to Treat?

The difficulty in treating breast cancer lies in its biological diversity. Each subtype of breast cancer exhibits unique molecular and genetic features, requiring tailored therapeutic strategies. A treatment that works for one subtype may be completely ineffective for another.

Several key factors complicate treatment:

1. Tumour Microenvironment: Cancer cells manipulate nearby healthy cells to support their growth and survival. These surrounding cells can form a protective barrier, making it harder for drugs to reach the tumour effectively.
2. Drug Resistance: Over time, breast cancer cells can evolve and become resistant to therapies such as chemotherapy, hormonal therapy, or targeted drugs. They may activate alternative signaling pathways or mutate further to avoid destruction.
3. Metastasis: Once cancer spreads to other organs, treatment becomes significantly more complex. Metastatic cancer cells may behave differently from those in the original tumour, requiring new strategies for management.

     5.Immune Evasion: Cancer cells can sometimes avoid detection by the immune system. In breast cancer, this is especially          problematic because the disease often lacks sufficient genetic mutations to make the cancer cells “visible” to immune       cells. 

5.Variable Response to Immunotherapy: Although immunotherapy has shown promise in treating cancers like melanoma and lung cancer, it has limited effectiveness in breast cancer. This is partly due to the low number of mutations in breast cancer cells and their ability to suppress immune activity.

The Role of Precision Medicine in Breast Cancer Treatment

Precision medicine offers a promising path forward in breast cancer care. This approach involves tailoring medical treatment to the individual characteristics of each patient, including their genetic profile, lifestyle, and the specific features of their tumour.

Key benefits of precision medicine include:

• Targeted Therapies: Treatments can be developed to target specific mutations or proteins present in a patient’s tumour, increasing effectiveness and reducing unnecessary side effects.
• Adaptive Treatment Plans: By using tools like liquid biopsies (e.g., blood tests), clinicians can monitor how a tumour evolves during treatment and adjust therapies accordingly.
• Early Detection and Prevention: Genetic testing can identify individuals at high risk, enabling earlier surveillance and potentially preventive strategies.

Precision medicine has already transformed the treatment landscape for certain breast cancer patients, especially those with access to genetic profiling and advanced diagnostic tools. While affordability and access remain challenges, ongoing research and clinical trials are expanding the reach of these personalized therapies.

Breast cancer remains a leading health concern for women worldwide due to its complexity and ability to resist conventional treatments. However, advances in understanding tumour biology and the development of precision medicine are creating new opportunities for more effective and personalized care. Continued investment in research, early detection, and access to precision therapies will be essential in improving outcomes and saving lives.