A small tumor had been removed from his liver during an operation on August 3, but scans had found four other small “spots” of the cancer, each about 2 millimeters in diameter, in his brain, he said. He was to begin radiation treatment later that day, he added, and had already begun taking an immune-system-boosting drug approved only last year for the treatment of advanced melanoma.
Carter, who will turn 91 in October, did not talk about his prognosis,whereas he described his diagnosis and treatment as “a new adventure.”
Melanoma is a type of skin cancer. It originates in pigment-producing cells, called melanocytes, in the basal (innermost) layer of the skin. The precise cause of the disease is unknown, but exposure to ultraviolet rays from the sun (and from tanning beds) is believed to be a major trigger of the DNA damage that leads to the cancer’s formation.
According to the National Cancer Institute, melanoma accounts for 4.5 percent of all new cancers in the United States. About 73,000 new cases will be diagnosed this year, and almost 10,000 people will die from the disease.
To learn more about melanoma, MinnPost spoke with Dr. Peter Lee, a dermatologic surgeon and associate professor at the University of Minnesota Medical Center. A lightly edited version of that discussion follows.
MinnPost: We think of melanoma as skin disease, not as a cancer that appears first in internal organs, such as the liver and brain. How would that happen?
Peter Lee: Melanoma is the deadliest form of the skin cancers that we treat. It’s usually caused by extensive sun exposure, although not all the time. In most circumstances, if caught early and if it’s just on the skin — and if you remove that portion surgically — then that’s typically a cure. But if the melanoma has invaded significantly and has travelled, via either the lymphatic [system] or the bloodstream, it can travel to other parts of the body, like the liver, like the brain, like the lung. It can then be fatal if not treated.
MP: It can also occur in the eye, correct?
PL: Yes. You can get melanoma on the surface of the eye or on the retina, in the back of the eye.
MP: Is that also caused by sun exposure?
PL: Usually, the ones on the surface of the eye are caused by sun exposure. But the ones on the retina, they can be from a preexisting mole. Those are probably not caused by the sun.
We do see a certain percentage of patients — actually quite a few — for whom we never find out what the source was. They present with metastatic disease. They have a seizure or headache or abdominal pain, and the next thing you know they have a melanoma on the inside of their body, and they’ve never had a history of anything being removed from their skin. And, on examination of their skin, there’s nothing that looks like a melanoma.
MP: Will President Carter’s age be a factor in his treatment and prognos?
PL: President Carter is 90 years old. But I would say that age is not a factor in how you treat melanoma patients. It’s really all about their overall health. He’s healthy. He’s a vibrant person. I think they should do what’s necessary to try and eradicate his tumors. I have seen miracles happen with this disease, especially with the newer drugs that are out there.