President Jimmy Carter was diagnosed with melanoma in the summer of 2015. While melanoma usually begins on the skin, it can sometimes develop in other parts of the body. President Carter’s melanoma first showed up on his liver. When doctors removed the tumor on his liver and a portion of his liver in early August 2015, they discovered that the cancer had spread. Four lesions were found on President Carter’s brain.
His treatment plan consisted of targeted radiation to his brain and a new medication called Keytruda - generically pembrolizumab. This medication is an immunotherapy drug that was approved for the treatment of melanoma in 2014.
Immunotherapy is different than chemotherapy. In chemotherapy, different drugs are used to kill the cancer cells but normally, there are many side effects, such as hair loss and stomach upset. Immunotherapy works by either boosting the immune system or enabling it to recognize and attack cancer cells. There are far fewer side effects to this type of treatment.
Some cancers, including some types of melanoma, “trick” the immune system. They disguise themselves as normal cells by producing a protein found in healthy cells. The immune system doesn’t see them as foreign and ignores them, allowing them to continue growing out of control.
President Carter was placed on a regimen of receiving Keytruda every three weeks. In trials, this medication was found to shrink tumors by as much as 90 percent. Between 30 and 40 percent of patients in the trials had a significant decrease in their tumors, with 5 percent achieving complete remission. When combined with other treatments, the percentage of people who had tumors significantly decrease was higher - between 50 and 60 percent. Other treatments could include additional immunotherapy drugs, chemotherapy or radiation, as President Carter received. Even after therapy ends, immunotherapy treatments continue to work. Clinical trials have found that between 70 and 80 percent of tumors continue to shrink.
President Carter is still receiving treatments. He has announced that he will still be receiving Keytruda treatments every three weeks.
President Carter credits Keytruda for helping him. In early December 2015, he announced in front of his Sunday School class that he was “cancer free.” Experts caution that this doesn’t mean he is cured. With immunotherapy, small cancer cells can remain hidden and some people experience a relapse in two to three years after treatment ends.
With Keytruda, President Carter, like others who took this medication, did not experience side effects. During treatment, he continued to work on humanitarian projects - including participating in building a house for Habitat for Humanity and working at the human rights foundation he founded, The Carter Foundation.
Keytruda is currently being tested on other types of cancer. It is approved for the treatment of melanoma, but may also help fight bladder, colon, kidney, breast, Hodgkin lymphoma, multiple myeloma (a type of blood cancer) and some types of head and neck cancer.