No more chemotherapy for breast cancer?

Kozhikode: Breast cancer treatment is witnessing a paradigm shift with the emergence of targeted therapies—personalized medicines that attack cancer at its genetic roots, sparing healthy cells from the widespread damage caused by traditional chemotherapy.

Speaking on this pressing issue, Dr Monika Pansari, Consultant – Breast and Gynaecology Onco-surgery (Surgical Oncology) and Robotic Surgery at Manipal Hospital, Kanakapura Road, said that this new approach, often termed as precision oncology, is changing the way doctors diagnose and manage breast cancer.

“Genomic profiling is now becoming an integral part of cancer care,” Dr Pansari said. “By understanding the genetic and molecular makeup of a tumor, we can tailor treatment that specifically targets cancer-causing mutations.”

What Are Targeted Therapies And How Does It Work (Inputs: Dr Pansari)

Targeted therapy for breast cancer represents a major shift from traditional chemotherapy by focusing on the unique biological features of cancer cells. 

These therapies can be delivered in different forms—through oral pills or capsules taken at home, intravenous (IV) infusions administered directly into a vein, or subcutaneous injections given under the skin.

The mode of administration depends on the specific drug being used. These therapies may be prescribed alone or in combination with other treatments, such as chemotherapy, to enhance effectiveness and improve patient outcomes.

Instead of attacking all rapidly dividing cells, these therapies are designed to pinpoint specific proteins or genetic mutations that drive tumor growth and survival.

The drugs, which include monoclonal antibodies and small-molecule inhibitors, block the signals that help cancer cells grow, spread, or repair themselves.

They can be used on their own or in combination with other treatments to improve outcomes and reduce side effects.

Common targets include the HER2 protein, BRCA gene mutations, and pathways like PI3K/AKT/mTOR that are crucial for cancer cell survival.

Monoclonal antibodies are one of the most well-known types of targeted therapies. These lab-engineered proteins attach to specific markers on cancer cells—either blocking the growth signals that fuel tumors or marking the cells for destruction by the immune system.

By focusing on the molecular drivers of the disease, targeted therapy offers patients a more personalised, effective, and gentler approach than conventional chemotherapy.

A Shift from One-Size-Fits-All to Personalised Care

Traditional chemotherapy works by attacking all rapidly dividing cells—both cancerous and healthy—leading to side effects such as hair loss, nausea, and fatigue. In contrast, targeted therapies are designed to act only on specific molecular changes that drive cancer growth.

This selective mechanism not only enhances treatment effectiveness but also significantly reduces side effects.

Targeted Drugs Revolutionising HER2-Positive and Hormone-Receptor Cancers

HER2-positive breast cancer, which accounts for nearly 20% of all breast cancer cases, has seen major advancements with drugs like Trastuzumab, Pertuzumab, and Trastuzumab Deruxtecan.

“These medications directly target the HER2 protein responsible for aggressive tumor growth and have improved both survival rates and recurrence outcomes,” says Dr. Pansari.

Similarly, in hormone receptor–positive breast cancers, treatments have evolved with the addition of CDK4/6 inhibitors such as Palbociclib, Ribociclib, and Abemaciclib. These drugs, when used with hormonal therapy, slow disease progression and enhance overall survival.

Another major development is the introduction of PARP inhibitors like Olaparib, which work by blocking cancer cells’ ability to repair their DNA—an approach particularly effective in patients with BRCA gene mutations.

The Future: Precision and Immuno-Oncology

Research is now expanding into targeting the PI3K and AKT pathways and exploring immune-based therapies that harness the body’s defense mechanisms to fight cancer more effectively.

“The future of breast cancer treatment lies in personalisation,” Dr Pansari emphasised. “We are moving toward a time when every therapy will be guided by the molecular fingerprint of the patient’s tumor.”

As targeted and immune therapies advance, experts believe they could one day replace chemotherapy for many breast cancer patients—offering hope for more effective and less toxic treatment options.