Introduction
Around 2,001,140 new cases of cancer will be diagnosed in the United States alone, with over 600,000 people dying from the disease. Nearly everyone has been affected by cancer, whether by losing a loved one or dealing with a personal diagnosis. Traditional treatments for cancer involve surgery, radiation, and chemotherapy. However, all of these options take a harsh toll on the body. For example, chemotherapy can cause infertility, heart or nerve damage, fatigue, hair loss, nausea, and numerous other painful side effects. Additionally, these therapies are often not enough on their own, and cancer remains a deadly diagnosis. But, a promising breakthrough known as immunotherapy offers new hope in the fight against cancer by using the body’s own immune system to target and destroy cancer cells. This evolving approach has already revolutionized cancer care, making many wonder if a cure is within reach.
What is immunotherapy
Immunotherapy is a new cancer treatment that trains your body's immune cells to target cancer. Cancer is often able to mask itself from the immune system, but immunotherapy enables the body to find and kill more cancer cells while producing more immune cells that effectively target cancer.
There are several types of immunotherapy, such as immune checkpoint inhibitors, which block proteins that prevent immune cells from attacking cancer, and adoptive cell therapy -which involves CAR T-cell therapy and tumor-infiltrating lymphocytes. CAR-T cell therapy involves extracting a patient’s T cells (a type of immune cell), genetically engineering them to express chimeric antigen receptors (CARs) that can specifically recognize cancer cells, and then reintroducing them into the patient’s body. On the other hand, tumor-infiltrating lymphocyte (TIL) therapy involves harvesting immune cells that are naturally present in a patient's tumor. These TILs have already recognized cancer cells as abnormal, but their numbers and effectiveness are often insufficient to completely destroy the tumor. In the lab, TILs are expanded into large quantities and then re-infused into the patient
Other immunotherapeutic options include monoclonal antibody therapy, cancer vaccines, and immunomodulatory drugs. Monoclonal antibody therapy involves lab-made antibodies that can deliver drugs, toxins, or radioactive material to cancer cells. Cancer vaccines use cancerous cells to train your body to identify cancer antigens, like a traditional vaccine. Although still experimental, the FDA has approved multiple cancer vaccines. Finally, immunomodulators are molecules that boost your body's response to cancer. Immunomodulatory drugs help to stimulate the body’s immune system to recognize and attack cancer cells more effectively. For example, drugs like cytokines can boost the immune system’s ability to respond to cancer cells.
Current Limitations
Despite the promising aspects of immunotherapy, some challenges still exist. Immunotherapy does have side effects caused by these boosted immune cells attacking our own tissues. These side effects are known as immune-related adverse effects (irAE) and include fatigue, rashes, nausea, altered hormone levels, and diarrhea. Around 20% of people who receive immunotherapy will experience one or more of these side effects.
Furthermore, immunotherapy does not work for all types of cancer, and not all patients will respond to immunotherapy. On top of that, during prolonged periods of immunotherapy, some tumors develop resistance to treatment. This resistance can occur when cancer cells adapt to avoid recognition by immune cells or alter their microenvironment to suppress immune activity. This poses a significant challenge for long-term effectiveness. Also, in its current state, immunotherapy can be expensive and not widely accessible to all patients, which limits its use in many healthcare systems. Finally, the complexity of immune responses can make it difficult to predict which patients will benefit from treatment, requiring more research to identify reliable biomarkers for treatment response.
Conclusion
Immunotherapy holds promise as our understanding of cancer and immunology continues to evolve. Despite the current limitations of immunotherapy, researchers are working on ways to improve immunotherapy. One area of focus is identifying biomarkers that predict which patients will benefit the most from specific types of immunotherapy. Immunotherapy is at the forefront of cancer research. And while challenges remain, the future looks promising as new techniques and combinations continue to be developed. If successful, immunotherapy could revolutionize cancer treatment, offering hope to patients who previously had limited options.
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