Neither one is universally better. That answer frustrates people who want a clear winner, but it’s the only honest one. Immunotherapy has produced results in certain cancers that chemotherapy never did durable responses in advanced melanoma, lung cancer, and bladder cancer that would have been unimaginable twenty years ago. But immunotherapy works only when the tumour biology supports it. For cancers that are immunologically cold — tumours that don’t express the right markers, don’t attract immune cells, and don’t respond to checkpoint blockade chemotherapy remains the primary systemic treatment. The comparison only makes sense when you know which cancer, which molecular profile, and which stage you’re actually talking about.
According to Dr. Sandeep Nayak, Best Cancer Treatment in Bangalore, “Patients come in asking whether immunotherapy is better than chemo the way they’d ask whether one painkiller is better than another. It’s the wrong frame. Immunotherapy works through a completely different mechanism. Chemotherapy kills dividing cells. Immunotherapy removes the brake that’s stopping your immune system from attacking cancer cells. Which one belongs in a treatment plan depends entirely on what the tumour is doing biologically, not on which sounds more modern.”
Facing a treGet personalised cancer treatment guidance based on your cancer type, stage, and treatment goals.atment that doesn’t seem to be working?
Immunotherapy vs Chemotherapy — How They Actually Work
|
Chemotherapy |
Immunotherapy |
|
|
Mechanism |
Kills rapidly dividing cells directly |
Activates the immune system to recognise and attack cancer cells |
|
Target |
All rapidly dividing cells — cancer and healthy |
Specific immune checkpoints or cancer markers |
|
Who it works for |
Most cancer types across almost all stages |
Cancers with high PD-L1 expression, high TMB, or MSI-high status |
|
Response pattern |
Predictable — tumour shrinks during treatment |
Variable — some patients have dramatic responses, some have none |
|
Side effects |
Hair loss, nausea, fatigue, bone marrow suppression |
Immune-related adverse events — skin, gut, lung, liver, thyroid |
|
Duration |
Fixed cycles — typically 3 to 6 months |
Can continue for months to years |
|
Resistance |
Develops in many cancers over time |
Less common but occurs — especially in tumours with low immunogenicity |
|
Cost |
Generally lower |
Significantly higher — checkpoint inhibitors are expensive |
Both are used alongside surgery in combined treatment plans. The question is sequencing and selection, not which replaces the other.
When Immunotherapy Wins and When Chemotherapy Is Still the Right ?
Where immunotherapy has changed outcomes?
Melanoma was proof of concept. 5 year survival went from under 40% for median survival to above 40% with checkpoint inhibitors. Lung cancer followed, pembrolizumab now outperforms chemotherapy as first line in high PD-L1 cases. MSI-high colorectal, bladder, and certain head and neck cancers are also areas where immunotherapy now plays a primary role.
What makes a tumour likely to respond?
PD-L1 expression is the most tested marker, higher expression means better response. Tumour mutational burden matters too, more mutations means more targets for the immune system. MSI-high status typically predicts a strong response. Without these markers, response rates can drop to around 5%.
Where chemotherapy remains the answer?
Triple-negative breast cancer, RAS-mutated colorectal cancer, most gastric cancers, and pancreatic cancer still rely primarily on chemotherapy. Pembrolizumab gets added in high-risk TNBC based on KEYNOTE-522, but alongside chemotherapy, not instead of it.
When both are used together?
Chemo-immunotherapy combinations are now standard in several cancers. Chemotherapy kills cells and releases antigens the immune system can then recognise, priming the response immunotherapy builds on. KEYNOTE-522, KEYNOTE-590, and several lung cancer trials have shown this combination outperforms either alone. For a direct comparison of immunotherapy versus targeted therapy, the previous blog on Immunotherapy vs Targeted Therapy: Which Is Better covers that distinction in detail.
Why Choose MACS Clinic for Cancer Treatment??
Dr. Sandeep Nayak’s team at MACS Clinic doesn’t recommend immunotherapy or chemotherapy based on cancer type alone. Molecular profiling PD-L1 expression, TMB, MSI status, receptor and mutation testing is completed before any systemic treatment is confirmed. The treatment that gets prescribed is the one the tumour biology actually supports, not the one that fits a general protocol for that cancer site.
Every case goes through a tumour board review before treatment starts. Where combination chemo-immunotherapy is indicated, the sequencing is planned before the first cycle, not adjusted reactively when one approach stops working. Those who want to discuss their treatment options can reach the team at +91 8035740000 or through the contact page.
FAQs
Is immunotherapy always better than chemotherapy?
No. Immunotherapy outperforms chemotherapy in specific cancers with the right biomarkers. In tumours that are immunologically cold or lack predictive markers, chemotherapy remains more effective.
Can immunotherapy and chemotherapy be used together?
Yes, and in several cancers this combination is now standard. Chemotherapy can prime the immune response that immunotherapy then amplifies.
Does immunotherapy have fewer side effects than chemotherapy?
Different side effects, not necessarily fewer. Chemotherapy causes bone marrow suppression, hair loss, and nausea. Immunotherapy causes immune-related adverse events affecting the skin, gut, lungs, liver, and endocrine glands which can be serious and require immunosuppression to manage.
How do doctors decide between immunotherapy and chemotherapy?
Biomarker testing PD-L1 expression, tumour mutational burden, MSI status, and molecular profiling determines which approach the tumour is likely to respond to. Without that testing, the decision is a guess.
Reference
- Ribas A, Wolchok JD. Cancer immunotherapy using checkpoint blockade. Science, 2018. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6028746/
- National Cancer Institute. Immunotherapy to Treat Cancer. https://www.cancer.gov/about-cancer/treatment/types/immunotherapy
Disclaimer:This content is published for educational and informational purposes only.