In 1980 Billy Starr turned his passion for extreme bike rides into a pioneering event supporting cancer research. Starting from his dad's dining room table, Starr built the Pan-Mass Challenge bike-a-thon into the country's most successful athletic fundraiser and legacy-setter in sports philanthropy.

 In its first 33 years, the PMC raised $375 million for Boston's Dana-Farber Cancer Institute, with many of more than 9,000 participants reinvigorating their stake in the forging of new cures. Whether riding as many as 192 miles or helping out at water stops and hubs, PMC participants...