Suraj Venna, MD, is board certified in dermatology. He is the medical director of the Inova Melanoma and Skin Cancer Center. Dr. Venna specializes in detecting and treating skin cancer. Read Dr. Venna’s profile.
The 39th president of the United States is doing well! Former President Jimmy Carter was diagnosed in August with metastatic melanoma in the brain and liver. On Sunday, November 29, he revealed to his congregation that he is cancer-free. Carter has been able to continue his weekly sermons to his congregation and resume his activities with Habitat for Humanity.
Since his diagnosis, his treatments have included:
- Partial liver resection
- Radiation to the brain lesions
- Immunotherapy medication called pembrolizumab (Pembro)
Melanoma: Immune Cells Under Attack
The programmed cell death molecule, known as PD-1, plays an important role in regulating our immune system. Under normal conditions, the PD-1 receptor, located on the surface of T-cells, acts as a “checkpoint,” preventing the immune system and T-cells from becoming overactive. This is called self-tolerance. Without this checkpoint, our bodies would succumb to serious autoimmune conditions.
The PD-1/PD-L1 pathway is one of the key checkpoints for melanoma cells. These melanoma cells block the T-cells from mounting a robust and sustained fight against the cancer cells that are roaming through the blood stream and infiltrating organs.
Pembro: The Latest in Melanoma Treatment
The PD-1 protein is on the surface of T-cells. The PD-L1 protein, however, is on the surface of the melanoma cancer cells. Immunotherapy, such as Pembro, a protein antibody, is known as a “checkpoint” inhibitor. It can bind to the T-cells and prevent the cancer cells from binding. This allows the T-cell to get turned on, so they can mount a response to the melanoma.
Is There an Age Limit for Pembro?
One question we get frequently is, “How old can a patient be to take Pembro?” In the clinical trials used to study Pembro, nearly 40 percent of patients were older than 65 years of age. Remarkably, we did not find any differences in effectiveness and safety when comparing its use in older or younger patients.
At this point, Carter will continue on the infusions of Pembro every three weeks for an indefinite period. We are guardedly optimistic about his future success.