(Chemotherapy Advisor) – Patients with advanced stage melanoma may have promising combination therapy, a team of researchers from Memorial Sloan-Kettering’s Ludwig Center for Cancer Immunotherapy report. The combination therapy is the result of a rare phenomenon in radiotherapy, known as the abscopal effect. The study, which was published in the March 8 issue of The New England Journal of Medicine, and is titled “Immunologic Correlates of the Abscopal Effect in a Patient with Melanoma”, describes the abscopal effect in patients with melanoma treated with the immunotherapeutic agent ipilimumab (Yervoy) and radiotherapy.
The authors of the study define the phenomenon as follows: “The abscopal effect is a phenomenon in which local radiotherapy is associated with the regression of metastatic cancer at a distance from the irradiated site.” The authors write that this phenomenon may be mediated by activation of the immune system by the synergistic effects of radiotherapy and inhibition of an immunologic checkpoint on T-cells — cytotoxic T-lymphocyte-associated antigen 4 (CTL-4) — by treatment with ipilimumab. Despite being a rare phenomenon, the abscopal effect has been reported in several cancer types: kidney, melanoma, and lymphoma.
In this single patient case study, treatment with ipilimumab and radiotherapy resulted in “tumor shrinkage with antibody responses to the cancer-testis antigen NY-ESO-1, changes in peripheral-blood immune cells, and increases in antibody responses to other antigens after radiotherapy,” the study investigators write. The researchers concluded that the combination therapy could be a promising approach to treating advanced melanoma patients.