When deciding who to choose for President, voters have to weigh a lot of factors: Who’s on the “right” side of pivotal issues; who’s most likely to remain calm, focused and decisive in times of strife; and even whether a candidate is likely to survive his term in office. The last is something that many people have been discussing with regard to John McCain. If he wins the Presidential election in a little more than a week, he’d be the oldest incoming commander-in-chief.

Age, however, is no reliable gauge of life expectancy. Many people die in their 20s of accidents or even the occasional cancer. On the other hand, one of my grandmothers died at 88, the other at 100, and both of my grandfathers lived into their 90s. So the fact that John McCain is 72 does not indicate whether he’ll outlive Barack Obama (25 years his junior) much less the Republican candidate’s 44-year-old running mate, Sarah Palin. Indeed, working in McCain’s favor are good genes: His 96-year-old mom is still around to vote for him.

However, an individual’s medical history can point to special vulnerabilities. And McCain has one that his opponent does not: a history of cancer.

In the Oct. 25 Lancet, internist John Alam reviews what has been publicly released about the lesion removed from McCain eight years ago. It was melanoma, an especially malignant form of skin cancer. And at 2.2 millimeters thick, he says, McCain’s cancer fell into a “higher risk” category, based on something known as a Schuchter scale. Indeed, Alam writes, the Arizona senator’s predicted 10 year survival at the time of diagnosis was only 24 percent,” owing to his age at that point, his gender, and the fact that the cancer developed on the main part of his body — not an extremity.

Findings from another study that Alam cited would indicate that melanoma survivors who had initially developed a lesion as thick as McCain’s could expect to face a 12 percent risk of cancer recurrence in the ninth and the tenth years following surgery (as in 2009 and 2010) — a risk that would not be expected to decline for several years thereafter.

However, Alam points out, most such long-term-risk estimates derive from data compiled before melanoma patients were routinely biopsied for signs that their cancer had spread to lymph nodes. McCain’s lymph nodes were biopsied and showed no evidence of metastasis. So, Alam concludes, the Republican candidate’s prognosis “should be better than for the overall population in the Schuchter model.”

Two studies have focused on short-term prognosis of cancer recurrence for lymph-node-negative melanoma survivors (based on a median three-year follow-up of patients in each study). These investigations indicated that death rates from cancer recurrence in such patients were only half of that seen in melanoma survivors whose cancers had spread to lymph nodes.

Extrapolating these preliminary estimates to long-term survival, Alam says, would suggest that “McCain’s mortality risk due to melanoma is better but not eliminated, remaining at 6 percent per year.”

Is that a big deal? Well, McCain will probably have significantly better medical surveillance and care than the rest of us, should he reach the Oval Office. And early detection greatly increases an individual’s chances of survival. So I’m not too concerned that melanoma poses a huge risk.

Indeed, I would expect that for any President, stresses associated with the job — especially coping with crises such as running a war, countering threats of domestic terrorism, and reviving a devastated financial system — would pose a far greater risk of heart attack or stroke.

So why did Alam raise the issue of McCain’s melanoma? One can only guess. For what it’s worth, the Cambridge, Mass.-based physician acknowledges that “I have made voluntary contributions to the Democratic party and [Obama], but otherwise declare that I have no conflict of interest.”

Janet Raloff

Janet Raloff is the Editor, Digital of Science News Explores, a daily online magazine for middle school students. She started at Science News in 1977 as the environment and policy writer, specializing in toxicology. To her never-ending surprise, her daughter became a toxicologist.

More Stories from Science News on Health & Medicine

From the Nature Index

Paid Content