Improving Chemotherapy Response Rates for Melanoma Patients: Case Study Provides Possible Clue

Sunday, May 6, 2012 - 8:54pm
Section Chief, Soft Tissue and Melanoma & Director, IL-2 Program, Department of Medicine

Over the last year, we have made great progress in melanoma research. This research has provided us with a better understanding of this deadly disease and has also led to new treatments.

The drug ipilimumab, which was approved in March 2011 by the Food and Drug Administration (FDA), is one of these research discoveries. Ipilimumab is a form of immunological therapy, meaning it helps to boost a person’s immune system by priming it to target and help fight the melanoma cells. Though the drug has only about a 10% response rate, similar to other available melanoma chemotherapy agents, it has demonstrated a long-term effect on controlling the disease in those patients who do show a response.

So that leaves us with our next important research challenge: how do we improve the response rate of immunotherapies like ipilimumab? In other words, what do we have to do to increase the number of patients who respond to the drugs?

A recent paper published in The New England Journal of Medicine may provide some insight into one possible solution.

The paper reported a single case study about a young woman with stage IV melanoma whose disease was progressing despite treatment with ipilimumab. The tumor had begun to grow near the spine, which put her at major risk of paralysis, so her doctors began radiation treatment to the tumor. Throughout her radiation treatment, she also continued receiving ipilimumab.

Her doctors began to notice that other tumors in her body, although not targeted with radiation, began to shrink. This effect, not unheard of but rarely documented, is known as the abscopal effect, or when localized radiation therapy causes tumors outside the field of radiation to shrink or disappear completely.

To explore why this occurred, the doctors then looked at the tumor tissue to check for the NY-ESO protein. It has been shown that immunity to the NY-ESO protein may be a predictor to a response from ipilimumab.

Although the paper reported on a single patient only, it paves the way for further investigation into the effect of combination treatment with radiation and chemotherapy, and, it is hoped, future breakthroughs in melanoma treatment.