Revolutionising cancer treatment: The synergy of radiation oncology and immunotherapy

Dr Vividha Dubey, MD Radiation Oncology, HCG hospitals emphasises that the complementary modes of action of radiation oncology and immunotherapy contribute to their synergy. Radiation therapy not only kills cancer cells directly, but it also changes the tumor microenvironment, making it more prone to immune response

Cancer has long been one of modern medicine’s most powerful rivals, costing millions of lives worldwide. While substantial progress has been made in cancer treatment, the search for more effective and less invasive medications continues. In recent years, the merger of radiation oncology and immunotherapy has emerged as a game-changing technique, giving cancer patients a fresh hope, and significantly increasing treatment outcomes.

Traditionally, radiation therapy and immunotherapy were seen as separate concepts in the fight against cancer. For decades, radiation therapy has been a cornerstone in cancer treatment, involving the use of high-energy X-rays or other particles to target and treat cancer cells. Immunotherapy, on the other hand, uses the immune system’s ability to recognise and remove cancer cells. Each method has its own advantages, but their combined effect has proven to be synergetic.

Understanding the synergy

The complementary modes of action of radiation oncology and immunotherapy contribute to their synergy. Radiation therapy not only kills cancer cells directly, but it also changes the tumor microenvironment, making it more prone to immune response. Radiation therapy functions as a “primer” for the immune system by stimulating the production of tumor antigens and producing a pro-inflammatory environment, making it easier for immune cells to recognise and target cancer cells.

Immunotherapy, on the other hand, boosts the immune system’s reaction. Checkpoint inhibitors and adoptive cell treatments, for example, can prevent immune cells from detecting and destroying cancer cells by blocking inhibitory signals. When paired with radiation therapy, immunotherapy can produce a powerful immune response that targets both the main tumor and distant metastases, resulting in better local and systemic disease management.

Clinical benefits

Combining radiation oncology and immunotherapy has shown clinical benefits in numerous cancer types, including melanoma, non-small cell lung cancer, and head and neck squamous cell carcinoma, and others. This combination approach can lead to:

• Enhanced tumor control: Radiation therapy not only minimises tumors but also triggers the immune system to seek out and eliminate leftover cancer cells, decreasing the chances of recurrence.
• Improved survival rates: Patients who undergo both radiation therapy and immunotherapy tend to have better prognosis than those who received either treatment alone.
• Reduced side effects: Immunotherapy paired with radiation therapy frequently has less side effects than traditional treatments such as chemotherapy, as immunotherapy is task targeted modality.
• Cure potential: The combination of radiation therapy with immunotherapy has resulted in positive response and even long-term cures in some cases, particularly in metastatic cancers.

Combining the techniques of radiation oncology with immunotherapy is one of the turning points in the fight against cancer. This combination has shown the ability to improve treatment outcomes, providing new hope to cancer patients. As research advances, we should expect to see even more ground-breaking discoveries and advanced treatments that capitalise on the synergy between these two effective techniques. Integration of radiation therapy and immunotherapy may become the standard of care in the near future, enabling more effective, less intrusive, and ultimately more successful therapies for cancer patients globally.