Immunotherapy
for Breast Cancer
What Is Immunotherapy?
Immunotherapy helps the body’s own immune system recognise and destroy cancer cells. In breast cancer, it is mainly used for triple-negative breast cancer (TNBC) — a subtype that lacks oestrogen, progesterone, and HER2 receptors and tends to be more aggressive.
Immunotherapy boosts the immune system’s response by blocking the “checkpoints” that cancer cells use to hide from immune attack.
When Is Immunotherapy Used?
Immunotherapy may be given:
-
Before or after surgery, alongside chemotherapy, for high-risk triple-negative cancers.
-
For advanced or metastatic TNBC, to slow disease progression and improve survival
Common Immunotherapy Drugs
-
Pembrolizumab (Keytruda®) – a PD-1 inhibitor that reactivates immune cells.
-
Atezolizumab (Tecentriq®) – a PD-L1 inhibitor used in selected TNBC cases.
These drugs are administered intravenously every 3–6 weeks, often in combination with chemotherapy.
How Immunotherapy Works
Normally, immune cells have checkpoints that prevent them from attacking healthy tissue. Cancer cells exploit these checkpoints to avoid detection.
Checkpoint inhibitors block this mechanism, allowing immune cells to find and kill cancer cells effectively.
Possible Side Effects
Most patients tolerate treatment well, but because immunotherapy activates the immune system, it can occasionally cause inflammation in healthy organs (immune-related side effects).
Common effects:
-
Fatigue, rash, or itching
-
Mild cough or diarrhoea
Less common but important:
-
Lung inflammation (pneumonitis)
-
Thyroid, liver, or hormone-gland inflammation
Your team will monitor for early signs and manage them promptly with medication or treatment breaks if needed.
Monitoring and Follow-Up
During treatment you will have:
-
Regular blood tests to check organ function
-
Physical examinations and imaging to monitor response
-
Ongoing communication with your oncology nurse and medical team
Side effects are usually reversible with early management.
Key Points
-
Stimulates the immune system to attack cancer cells.
-
Used mainly for triple-negative breast cancer.
-
Often combined with chemotherapy.
-
Requires careful monitoring for immune-related effects.
-
Delivered by an experienced oncology team at Breast & Wellness.