5. Mario Lemieux
In 1993, the Penguins were two-time defending Stanley Cup champions, thanks largely to the play of their superstar center, Lemieux. That January, he was on pace to challenge Wayne Gretzky's season record of 215 points when he announced he'd been diagnosed with Hodgkin's disease. He left the team for two months to undergo radiation treatment. When Lemieux returned to the ice on March 2 -- the same day he received his last radiation treatment -- he posted a goal and assist against the Flyers, and Philadelphia fans gave him a standing ovation.
34. Mario Lemieux
Super Mario led the league with 122 points in 1996-97, but injuries (particularly to his back) caused him to retire after the season. With that, the NHL lost one of its marquee players. After three seasons off the ice -- during which time he became a partial owner of the Penguins -- Lemieux laced up his skates again in 2000 at age 35. In his first season back, the Pens made it all the way to the conference finals. It was the franchise's best finish since winning consecutive Stanley Cups in 1991 and '92.