As the 2008 presidential election draws to a close, questions have arisen regarding the health of Republican presidential nominee John McCain, and his widely known struggle with melanoma. Speculation heightened in May of this year, when the candidate released around 1,200 pages of medical records to a restricted group of journalists, who were given limited access. Their reports indicated that in August of 2000, McCain underwent surgery to remove a melanoma, and that subsequent tests of his lymph nodes indicated the cancer had not spread.
Since then, controversy concerning the 72-year-old candidate's recovery has abounded throughout the blogosphere and mainstream media. Doubts about his health have become so pervasive that 47 percent of respondents in a recent poll said they were concerned that McCain would not finish a single term as president in good health.
Last week, The New York Times ran a long article reporting on the lack of information provided by the presidential and vice-presidential candidates, and presenting evidence suggesting that McCain's cancer might have been worse than his campaign—and even his personal doctors—have publicly acknowledged.
But the Times article and other recent reports fail to directly address and answer the most important question regarding McCain's cancer, the one that voters should consider when casting a ballot: What does Senator McCain's skin cancer mean for his future health and his ability to serve as president?
According to the publicly available information—information that includes the Times revelations but is still incomplete—it seems that the probability that skin cancer will interfere with McCain's health in the next few years is very low: no more than a couple percent.
Melanoma is the most severe type of skin cancer, and is documented at a rate of around 60,000 cases a year in the U.S. Each melanoma that is diagnosed is classified into one of four stages of severity based on a scale defined by the American Joint Committee on Cancer—stage I is the most innocuous, stage IV the most deadly. Stages are based on the size and depth of the tumor, the number of regional lymph nodes affected, and the number of metastatic sites that exist. Stages II and III can also be subdivided into "A", "B" and "C" substages (from least to most dangerous), depending on how deeply the tumor has penetrated the skin and whether the primary melanoma is ulcerated, meaning the skin covering aportion of the tumor is not intact.
McCain has had four melanomas, including a lesion on his shoulder that was removed in 1993 and has not returned, as well as melanomas on his upper left arm in 2000 and his nose in 2002 that were of the least dangerous kind, or in situ. According to reports, the melanoma removed from McCain's left temple in 2000 was the most serious, measuring 2.2 millimeters deep at its thickest point, and had not spread to any lymph nodes; it was thus graded a stage IIA. However, the Times reports that the medical opinions are inconsistent regarding the severity of the Senator's melanoma.
In particular, a pathology report done by the Armed Forces Institute of Pathology in Washington, which was based on a biopsy of the removed melanoma, suggests it may have spread from another melanoma. If this is the case, it would bump the tumor removed from his temple to a stage III. The Times quotes the report as saying, "The vertical orientation of this lesion with only focal epidermal involvement above it is highly suggestive of a metastasis of malignant melanoma and may represent a satellite metastasis of S00-9572-A."
"If [the temple melanoma] spread from a previous primary melanoma, then it's a stage III," Dr. Mark Naylor, an associate professor of dermatology at University ofOklahoma Health Sciences Center in Tulsa and a prominent melanoma researcher, told DISCOVER in an interview. "That's a crucial difference. Stages I and II are treatable and curable. Stage III and IV are advanced and very serious."
The Times also questioned why McCain's doctors had performed such "extensive" surgery, including removing 30 of McCain's lymph nodes, if the melanoma was in fact a stage IIA. However, the number of lymph nodes removed in and of itself doesn't necessarily mean that the melanoma was more serious. "For melanomas on the head and neck, it's always touchier," says Naylor. "It could be just that [McCain's] surgeons were being extra careful to look for advanced disease."
Reclassification of the melanoma significantly changes someone's chances of surviving 10 years after the incidence, and the Times points out the stark difference: "The reclassification would change his statistical odds for survival at 10 years from about 60 percent to 36 percent, according to a published study."
But the Times underplays the most important single piece of information about the risk to McCain's health from skin cancer: the fact that he has already survived more than eight years without a recurrence, which means that his chances of suffering a recurrence now are very low. "If you've had melanoma, 99 percent of the time if you're going to have a recurrence it will be within 10 years," Dr. Darrell Rigel, melanoma expert and clinical professor of dermatology at New York University Medical Center, told DISCOVER. "If a patient is 8.5 years out, [the likelihood] of recurrence goes on a curve: It's 95 percent at five years after treatment, 99 percent at 10 years. So [McCain, at 8 years] is at somewhere around a 1.5 percent chance of recurrence, though it's probably closer to one percent."
Crucially, the curve that measures the probability of recurrence is similar for a stage II or a stage III melanoma. "If you have a thicker tumor, your chance of dying is greater overall, and your peak time of dying is earlier," says Rigel. "But once you're out five years, the recurrence rate is the same. Once you hit 10 years, 99 percent of the risk you had is gone, no matter what your stage."
Most experts on melanoma agree that the chances for recurrence 8.5 years after a melanoma like McCain's are very slim. "If he's more than five years out, he'd probably never have another problem," said Dr. Svetomir Markovic, melanoma specialist at the Mayo Clinic in Minnesota, in an interview. "If you have a stage IIA or a stage III, it would be a different survival curve. But any patient, no matter what stage of melanoma it is, if they're OK for that many [eight and a half] years out, the odds of relapse decrease dramatically, to just a few percentage points."
Neither Rigel nor Naylor nor Markovic have examined McCain's medical records in particular, and they said without such access they couldn't give a true medical prognosis—their opinions are based on a generic profile defined by the information that's publicly available about McCain.
Some other media and medical reports have claimed that McCain may be facing much greater risks. One group of nearly 3,000 physicians have signed an open letter requesting that the Republican candidate release his medical records in full, claiming his chance of recurrence "could be higher than 60 percent," according to NewScientist. While it's possible that McCain's records could contain any number of negative indicators for his health, there would have to be a fundamentally novel information to override the dominating fact that 8.5 years after a melanoma, the chance of recurrence is very slim.