Combining radiation and immunotherapy shows promise for bladder cancer

A new review was published in Volume 16 of Oncotarget on May 19, 2025, titled "Advancements in bladder cancer treatment: The synergy of radiation and immunotherapy."

Researchers from the University of California, Irvine, led by Nazmul Hasan, reviewed recent clinical and scientific advances in combining radiation therapy with immunotherapy for bladder cancer. The article summarizes growing evidence that this combined approach may strengthen the immune response and improve long-term disease control. This strategy is especially important for patients who are not candidates for surgery or who respond poorly to conventional treatments.

Bladder cancer is a serious and frequent condition, particularly affecting older men. Traditional treatments-surgery, chemotherapy, and radiation-can be effective, but they often fail to prevent cancer reappearance in advanced cases. The review explores how combining radiation and immunotherapy could improve outcomes by helping the immune system detect and destroy cancer cells more effectively.

Radiation therapy destroys cancer cells and triggers the release of tumor signals that attract immune cells. Immunotherapy, including drugs like pembrolizumab and nivolumab, helps the immune system work better by blocking proteins that allow cancer to evade detection. Used together, these treatments may produce a stronger, more widespread anti-tumor effect, even at distant sites not directly targeted by radiation.

The review discusses several clinical trials that support this approach. One phase II study reported that combining radiation with the immunotherapy drug durvalumab led to promising survival rates and manageable side effects. Another trial in Australia tested pembrolizumab with radiation and chemotherapy, resulting in high tumor control and extended patient survival. However, the review also points out that other trials showed serious side effects when high doses or multiple immunotherapy drugs were used at once.

“Joshi et al. performed a phase II study to determine the safety and efficacy of combining radiation therapy with durvalumab, a PD-L1 inhibitor, in patients who were ineligible for surgery or cisplatin-based chemotherapy.”

While the combination approach is promising, the authors emphasize that more research is needed to refine this treatment strategy. One major challenge is determining which patients are most likely to benefit. Future studies should focus on identifying reliable biomarkers, such as tumor mutation burden or immune activity, to guide personalized treatment plans.

This review highlights the potential of combining radiation and immunotherapy to improve outcomes for bladder cancer patients. With continued research and careful treatment design, this approach could offer new treatment options for those facing aggressive or hard-to-treat forms of the disease.

Reference:

Hasan N., Yang D., Gibson S., Khaleghi B., Ziari R., Kalebasty A. Rezazadeh Advancements in bladder cancer treatment: The synergy of radiation and immunotherapy. Oncotarget. 2025;https://doi.org/10.18632/oncotarget.28723.