Be afraid. Be very afraid:

If Mr. McCain’s 2000 left-temple melanoma was a metastasis, as the Armed Forces pathologists’ report suggested, it would be classified as Stage III. The reclassification would change his statistical odds for survival at 10 years from about 60 percent to 36 percent, according to a published study. The greatest risk of recurrence of melanoma is in the first few years after detection. His age, his sex and the presence of the melanoma on his face increase the risk. The fact that Mr. McCain has had no recurrence for eight years is in his favor. But cancer experts see the 10th anniversary as an important statistical benchmark, and that would not occur until 2010.

In May, his dermatologist at the Mayo Clinic, Dr. Suzanne M. Connolly, said in the teleconference that though there was no way to predict with certainty Mr. McCain’s chance of a recurrence, she judged it to be less than 10 percent. But melanoma is known to be quirkier than most cancers; doctors cite occasional cases in which melanomas come back after 15 or 20 years.

Melanomas can spread to various areas in the body, including the skin and any internal organ. In general, such spreading means the melanoma would not be curable. Treatment would depend in part on what organ or tissues are involved and could include additional surgery, chemotherapy, biologics, vaccines and radiation. Many such treatments can be debilitating and impair an individual’s physical and mental stamina. If the patient was the president, the location of a recurrence and its treatment could raise the need to invoke the 25th Amendment, elevating the vice president to president, at least temporarily.

God save us all. Or vote Obama.

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