Exercise During Chemotherapy Enhances Immune Response Against Cancer

Recent research indicates that engaging in structured physical activity during chemotherapy and prior to surgical intervention can boost the body's immune response specifically within tumor environments. A pioneering pilot study conducted by the University of Surrey and Royal Surrey NHS Foundation Trust sought to explore how exercise might influence tumor immunity in patients with esophageal adenocarcinoma, a severe form of esophageal cancer.

The study involved a randomized controlled trial with 22 participants diagnosed with this cancer type. Half of the participants undertook a 16-week prehabilitation program that included supervised exercise sessions twice weekly during their chemotherapy phase, extending into the period leading up to surgery. The remaining patients received standard care without additional exercise interventions.

Post-surgical analysis of tumor samples revealed marked differences in immune cell infiltration, particularly an increase in CD8+ T cells and natural killer cells—both crucial for attacking cancer cells—in patients who participated in the exercise regimen. Gene expression profiling supported these findings, showing heightened activity in immune-related pathways. Additionally, participants who improved their aerobic fitness during the program demonstrated even stronger immune responses within their tumors.

Dr. Nicola Annels highlighted that, to their knowledge, this is the first human trial to demonstrate that structured exercise during chemotherapy can positively alter tumor immune microenvironments. The results suggest that prehabilitation may be a valuable strategy to bolster the effectiveness of cancer treatments by enhancing immune surveillance.

Building on these promising outcomes, the ongoing OPTIMUS trial aims to enroll 50 patients scheduled for surgery following neoadjuvant chemotherapy. Participants will be randomized into different exercise intensity groups to evaluate whether more vigorous activity could further amplify immune benefits. Early cases within this trial have shown remarkable tumor regression, with some tumors becoming undetectable during surgery, and patients experiencing improved fitness levels that facilitate surgical procedures and recovery.

Experts emphasize that these findings reinforce the importance of physical activity as a supportive therapy in cancer care, potentially leading to better treatment outcomes and quality of life. Patients interested in participating are encouraged to discuss this option with their medical teams or contact the researchers directly.

Source: https://medicalxpress.com/news/2025-06-chemotherapy-immune-cells-cancer.html