Cutting the televised fundraiser back from 22 1/2 hours will increase its potential audience and revenue, MDA Vice President Jim Brown said in a Chicago Tribune report.
Lewis, 84, has been a fixture on the show for decades, and his role in 2011 will remain important, but it may not be as its host, the newspaper reported.
"He'll definitely be asked to play a key role in our 2011 telethon," Brown said Friday. "Jerry will be asked to play a key role. And when I say 'key role,' 'key' is key."
The 2010 telethon broadcast from South Point Hotel in Las Vegas raised nearly $59 million in pledges and contributions to advance the MDA's research and service programs.
"I will be here as long as I breathe," Lewis vowed on the air this year; the fundraiser concluded its 2010 efforts on Sept. 6. Lewis is the MDA's national chairman.
"Key" doesn't necessarily mean host, Brown said.
"Again, we're in the process right now of figuring out what will make the best six hours," Brown said. "We'll be announcing talent, Jerry's role and other things later."
Brown said he didn't know how Lewis reacted to the decision to shorten the show.
'SNL': 'Anchorman 2' cast, One Direction sing 'Afternoon Delight' [VIDEO]
Exploding whale video goes viral on Internet