A look at Lance Armstrong's impressive and controversy-laden career.
1991: Becomes U.S. national amateur cycling champion.
1993: Crowned U.S. national cycling champion.
Oct. 2, 1996: Diagnosed with testicular cancer. The disease later spreads through his whole body.
1997: Founds Lance Armstrong Foundation for Cancer.
1997: Declared cancer-free after brain surgery and chemotherapy.
July 1999: Claims first Tour de France title, winning four stages.
2000: Wins second Tour. Secures time-trial bronze medal at the Sydney Olympics and finishes 13th in the road race.
April 17, 2005: Confirms he will retire after the 2005 Tour de France.
July 24, 2005: Wins seventh Tour before retiring.
Sept. 6, 2005: Claims he is considering coming out of retirement after being angered by drug allegations against him.
Sept. 9, 2008: Announces he will will attempt to win his eighth Tour, in 2009.
July 2009: Armstrong finishes third in the Tour.
May 2010: Armstrong's former teammate Floyd Landis, who was stripped of the 2006 Tour title for doping, launches allegations at Armstrong.
June 2, 2010: Announces via Twitter that the 2010 Tour de France will be his last.
July 2010: Finishes final Tour in 23rd place.
Feb. 16, 2011: Retires for second time.
May 2011: Denies claims made by former teammate Tyler Hamilton that they took performance-enhancing drugs together.
June 30, 2012: The U.S. Anti-Doping Agency confirms it will file formal doping charges against Armstrong.
Aug 24, 2012: Armstrong announces he will not fight the doping charges filed against him, insisting he is innocent.
Oct. 10, 2012: USADA releases lengthy report accusing Armstrong of massive doping conspiracy.
Oct. 17, 2012: Steps down as Livestrong Foundation chairman; Nike drops sponsorship of him.