New York doctors are reporting a medical marvel, of sorts: A patient with metastatic cancer that had spread throughout his body was virtually cured after just one focused dose of radiation targeting only a single tumor.
Memorial Sloan Kettering Cancer Center specialists published their unique single-patient study in the New England Journal of Medicine and said it could help shed light on the immune system's role in fighting cancer
The phenomenon, known as the “abscopal effect,” is extremely rare, but has been observed in a few cases of melanoma, lymphoma and kidney cancer, according to the study. Researchers said it occurs when radiation therapy delivered to a single tumor in a patient with advanced cancer results in the disappearance of tumors elsewhere in the body that have not been zapped.
"We are excited about these results, and what we have seen in this one patient proves the principle that adding radiation therapy to immunotherapy may be a promising combination approach to treatment for advanced cancer," said senior researcher Dr. Jedd Wolchok. "What we think is happening here is that the immune system's cancer-fighting response is turned up a notch with the addition of focused radiation."
In the case study, Wolchok and colleagues reported treating a patient with advanced melanoma using an immunotherapy called ipilimumab, recently approved by the U.S. Food and Drug Administration. The patient's skin cancer had grown and spread to the spleen, lymph nodes and an area near the spine. Doctors treated the patient with localized radiation therapy to the tumor near the spine. But after the treatment, doctors noted the tumor shrank significantly, but other areas where the melanoma had spread also benefited – despite the fact that they were not directly targeted by the radiation. The patient continues to do well more than one year since receiving the radiation therapy.
Scientists can’t explain how the approach works, but suggested that radiation may help stimulate the immune system to fight cancer. Ipilimumab is an immunotherapy that exploits the body's own immune system to attack cancer.
Researchers said the study suggests that the combination of ipilimumab and radiation may be a promising approach for the treatment of melanoma.
The work was supported, in part, by the National Institutes of Health, the American Cancer Society and the Melanoma Research Alliance.