Yacht "Oneida", 1895.

On July 1, 1893, under the headline "President Seeks Rest," the New York Times reported on President Cleveland leaving Pier A in lower Manhattan on his friend's yacht, the "Oneida," for a fishing trip to his summer home on Cape Cod. In fact, the relaxing trip was a ruse to cover for oral surgery the President would secretly undergo while at sea. The small cancerous tumor (with a couple teeth and a piece of the jaw) was removed through the mouth itself while on the open water by a team of six surgeons. Remarkably, the whole procedure was completed in only 90 minutes. Without a visible scar, and with the president's substantial mustache still in place, the incision was easy to hide. Cleveland worried that publicizing this health issues would lead to political and financial instability at a time when the country had just entered into a depression.

A few weeks after the trip a Philadelphia Press reporter named E.J. Edwards published a story about the surgery, which was flatly denied by the President; his staff went so far as launching a smear campaign to discredit the reporter. In 1917, long after the president's death, one of the doctors present published an article with the truth. Today the tumor can be seen at the Mütter Museum in Philadelphia.