Tumor-Directed Therapy and the Immune Response
Melanoma researchers at Mayo Clinic are evaluating the use of specific radiation techniques to overcome cancer-mediated immune evasion mechanisms.
The immune system in patients with disseminated melanoma (stage IV) is in a dysfunctional homeostasis of chronic inflammation, analogous to the way in which pregnancy leads to the suppression of immune effector cells and the polarization of the Th1/Th2 axis toward Th2.
In addition, the constant turnover of growing cancer cells may provide the immune system with a steady, low-concentration exposure to cancer antigens, producing immune tolerance in a manner similar to how allergy shots can be used to train the immune system to increase tolerance to certain allergens.
One possible way to overcome immune evasion in melanoma may be through the use of stereotactic body radiotherapy.
An observational study of immune responses following stereotactic body radiotherapy in oligometastatic melanoma
Sean S. Park, M.D., Ph.D.
Stereotactic body radiotherapy (SBRT) is a unique radiotherapy strategy that has been demonstrated to elicit a tumor-directed immune response in preclinical in vivo melanoma studies without the concomitant use of immunomodulating agents.
To better understand the effects of high doses of radiation delivered to tumors with modern SBRT technology, researchers at Mayo Clinic are looking at patients undergoing SBRT for oligometastatic disease for both tumor ablative effects and immunogenicity.
This is an observational study in which patients are followed with serial blood draws at predetermined intervals for various immune-related assays. Patients are also followed clinically for outcomes related to the SBRT.