st selections. Among the responses: Metallica, AC/DC and endorsement of his recent use of a song by the group Disturbed. At age 59, with 36 years of Army service after graduating from West Point, Dempsey comes across as energetic and athletic. Last year he underwent treatment for what his spokeswoman, Lt. Col. Alayne Conway, said Sunday was "head and neck cancer that presented itself as a tumor on the base of his tongue." She said his doctors have given him a clean bill of health. The story of Dempsey's rise to the top job in the military is remarkable, not least because just a month ago it was widely presumed that Marine Gen. James Cartwright was a lock for the post. Dempsey had just been sworn in for a four-year term as the Army's chief of staff, an assignment he clearly relished. A cup of coffee later, Dempsey is a Senate vote away from taking a much different job, one that will make him the senior military adviser to Obama. Cartwright's stock fell after the public release of a Pentagon investigation into claims of misconduct with a young female aide. The Pentagon's inspector general cleared Cartwright of the most serious claims, which suggested he'd had an improper relationship with the woman. But the investigation found that he mishandled an incident in which the aide was drunk and either passed out or fell asleep in his hotel room, where he was working. This would not be the first time Dempsey has changed course suddenly. When he was serving in 2008 as deputy commander at U.S. Central Command, which oversees U.S. military operations in the greater Middle East, Dempsey was picked to become the Army's top general in Europe. But he never made the move because the Central Command's top leader, Adm. William J. Fallon, resigned suddenly and unexpectedly. Dempsey took over as the acting commander until Gen. David Petraeus was confirmed for the job several months later. Dempsey then was given command of the Army's Training and Doctrine Command, at Fort Monroe, Va., where he developed the Army's thinking on how to prepare for future wars. There he preached "the gospel of adaptation" — a conviction that uncertain times demand that soldiers and their leaders be versatile, flexible and open to new ways of doing things. Dempsey, who grew up in New Jersey and New York, received a master's degree in English from Duke University in 1984 and then taught English at West Point. He also earned master's degrees from the Army's Command and General Staff College in 1987 and from the National War College in 1995. He has a reputation for embracing change. Peter Mansoor, who served under Dempsey in Iraq as a brigade commander in the 1st Armored Division, wrote in his book, "Baghdad at Sunrise," that Demps