An Overview of How Immunotherapy Is Used to Treat Cancer
Immunotherapy is a modern approach to cancer treatment that focuses on supporting the body’s own immune system in recognizing and responding to cancer cells. This article explains the basic principles behind immunotherapy, the different ways it is used in clinical practice, and how it differs from more traditional cancer treatment methods.
Cancer treatment increasingly includes approaches that work with the immune system rather than relying only on directly killing rapidly dividing cells. Immunotherapy can be used in specific cancer types and clinical situations, and it may be given as an infusion, injection, pill, or a personalized cell-based product depending on the method.
Immune System and Cancer Interaction
The immune system constantly scans the body for abnormal cells, using signals on cell surfaces to distinguish “self” from “non-self” or “danger.” Cancer can develop when tumor cells grow faster than immune defenses can control, and when tumors learn to hide by reducing recognizable markers or by creating an immunosuppressive environment around the tumor. Some cancers also exploit immune “checkpoints,” which are normal braking systems that prevent excessive inflammation, to keep immune cells from attacking effectively.
How Immunotherapy Works in Cancer Treatment
Immunotherapy works by strengthening immune recognition, boosting immune cell activity, or removing inhibitory signals that prevent an immune response. Checkpoint inhibitors, for example, can release the brakes on T cells so they can better attack tumor cells. Other strategies, such as monoclonal antibodies, can tag cancer cells for immune destruction or block growth signals that cancers use to survive. Some immunotherapies are designed to create long-term immune memory, which helps explain why a subset of patients can experience durable responses even after treatment stops.
Types of Cancer Immunotherapy
Cancer immunotherapy includes several distinct categories that are used for different diagnoses and stages. Checkpoint inhibitors (such as PD-1/PD-L1 or CTLA-4 inhibitors) are widely used across multiple cancers, while CAR-T cell therapy is a highly specialized approach that modifies a patient’s own T cells to recognize a specific target and is mainly used in certain blood cancers. Monoclonal antibodies can be “naked” antibodies, antibody-drug conjugates, or bispecific antibodies that bring immune cells and tumor cells together. Cancer vaccines and cytokine therapies exist as well, though their use varies and may be limited to particular settings.
Immunotherapy Compared to Traditional Cancer Treatments
Compared with chemotherapy and radiation, immunotherapy often has a different goal and a different side-effect pattern. Chemotherapy and radiation primarily aim to damage cancer cell DNA or disrupt cell division, which can also affect healthy fast-growing cells; immunotherapy aims to shift immune behavior so immune cells do more of the targeting. This difference can affect timing: immunotherapy responses may sometimes take longer to appear, and in certain cases tumors can look temporarily larger on scans due to immune cell infiltration. Side effects also differ; immunotherapy can trigger immune-related inflammation in organs (such as skin, gut, lungs, liver, or endocrine glands), which is managed differently than classic chemotherapy-related low blood counts or nausea.
Below is a fact-based snapshot of widely used cancer treatment approaches and selected, real-world examples of therapies or modalities used in the United States. Specific treatment choice depends on cancer type, stage, biomarkers, prior therapies, and overall health.
| Product/Service Name | Provider | Key Features | Cost Estimation |
|---|---|---|---|
| Pembrolizumab (Keytruda) | Merck | PD-1 checkpoint inhibitor used across multiple cancers with appropriate indications/biomarkers | Varies widely by dose, schedule, site of care, and insurance |
| Nivolumab (Opdivo) | Bristol Myers Squibb | PD-1 checkpoint inhibitor used in several solid tumors and some blood cancers | Varies widely; patient costs depend on coverage and assistance programs |
| Atezolizumab (Tecentriq) | Genentech | PD-L1 checkpoint inhibitor used in multiple settings (often biomarker- and cancer-specific) | Varies widely; facility-administered drug pricing differs by setting |
| CAR-T cell therapy (e.g., axicabtagene ciloleucel/Yescarta) | Kite Pharma (Gilead) | Personalized cellular therapy; complex manufacturing and inpatient/outpatient monitoring | Typically high total cost; depends on center, complications, and coverage |
| External beam radiation therapy | Hospital-based radiation oncology centers | Local treatment; often delivered in fractions over days to weeks | Varies by number of sessions, technology, and insurer |
| IV chemotherapy regimens | Hospital/infusion centers | Systemic cytotoxic treatment; regimen-specific dosing and cycles | Varies by drugs used, generics vs. branded agents, and setting |
Prices, rates, or cost estimates mentioned in this article are based on the latest available information but may change over time. Independent research is advised before making financial decisions.
In practice, clinicians compare these options by weighing expected benefit, side-effect risks, logistics (infusion time, monitoring, travel), and whether a tumor has biomarkers that predict response. Insurance design in the United States also matters: a therapy billed under pharmacy benefits can affect out-of-pocket costs differently than a therapy billed under medical benefits in an infusion center. Because many immunotherapies are administered over months and require monitoring for immune-related side effects, real-world cost is often shaped by the full episode of care, not just the medication itself.
Immunotherapy has changed cancer care by offering new ways to control disease, especially in cancers where immune checkpoints or targeted immune approaches are relevant. It is not interchangeable with chemotherapy, radiation, or surgery; rather, it is one tool among several, selected based on the biology of the cancer and the patient’s overall situation. This article is for informational purposes only and should not be considered medical advice. Please consult a qualified healthcare professional for personalized guidance and treatment.
