Tumor Blood Flow After Physical Exercise in Breast Cancer and Lymphoma Patients (Exetumor3 Study)

In regards to cancer, it would be reasonable to assume that also cancer behaves like all other inactive tissues in a body during exercise, meaning that also blood flow in the tumor environment is reduced particularly when exercise intensity increases. However, recent pre-clinical studies suggest that due to dysfunctional vasculature and blunted sympathetic constriction in the tumor, tumor blood flow is increased even by 200% compared to resting values (6; 18; 19) as increased cardiac output and blood pressure enhance perfusion pressure in the tumor. This improves its oxygenation (6; 18; 19), which is important as tumor hypoxia negatively affects the efficacy of treatment (27). Tumor hypoxia is promoted by heterogeneous blood flow in the tumor, but according to these pre-clinical studies exercise reduces the heterogeneity of tumor perfusion. However, it is not currently known if this is the case in patients, and it might be that tumor perfusion is actually decreased during exercise, but increased post-exercise, but this has never been addressed in clinical patients and is therefore the aim of the present study. Importantly, advanced imaging methods are available to investigate whether these pre-clinical findings can be extended to humans to serve as an evidence based proof-of-concept for the possible inclusion of exercise in the treatment of cancer during chemotherapy.

OBJECTIVES AND PURPOSE

The most important objective of this directly translatable and highly inter- disciplinary imaging, physical activity, health and medical research in the acute exercise study setting is:

To investigate whether acute moderate intensity exercise increases tumor blood flow

-It is hypothesized and expected that exercise increases tumor blood flow, documented as perfusion increase after acute exercise