Channel 4 led its 11 p.m. newscast last night with a Steve Burton report that Kessel was in Massachusetts General Hospital and had been diagnosed with testicular cancer.
Rumors circulated all day that Kessel had been hospitalized for any number of reasons, including testicular cancer or depression.
Bruins general manager Peter Chiarelli, when reached by the Globe at approximately 9 p.m., dismissed the notion that Kessel's issues were drug- or alcohol-related, but when asked if he cared to address whether Kessel had been diagnosed with either testicular cancer or depression, Chiarelli offered only, "No, I don't."
Kessel did not travel with the team yesterday to Montreal, and he will not play tonight against the Canadiens.
"The only thing I can say is that he's not available for the trip," coach Dave Lewis said. "He's not coming on the trip and he won't play. I'm not going to talk about Phil much more than that."
Lewis didn't have any comment when asked if he could guess at the length of Kessel's absence. Chiarelli said the club will determine at a later date whether Kessel will be placed on injured reserve.
"I just want to make it clear that it's not drug- or alcohol-related," Chiarelli said. "But out of respect for the family's wishes, I can't say more. Hopefully, we'll get some clarity in short order, which could mean this week.
"We all were [surprised], personally and collectively. But this happens in all walks of life. Our thoughts and prayers are with Phil and his family. We'll support him along the way and work our way through it.
"There's a bunch of strong character guys on this team on and off the ice. Phil is a strong, young individual and he's got a strong family. All those will be factors in getting him through this."
Kessel, the fifth overall pick of the 2006 draft, is one of eight Bruins who played in all 27 games so far this season, alternating between wing and center. Kessel had five goals and four assists, scoring one power-play goal while drawing four penalty minutes.
He spent last year at the University of Minnesota as a freshman, collecting 51 points in 39 games.