He is gaunt. His voice is raspy. And he has a new, undisclosed type of cancer that will require him to step away from the leadership of the federal New Democrats just months after the party achieved unprecedented electoral success.
But Jack Layton told reporters on Monday that his absence from politics will be temporary and he plans to return to work in September.
"I'm going to fight this cancer now, so I can be back to fight for families when Parliament resumes," he said. "I am hopeful and optimistic about the personal battle that lies before me in the weeks to come."
Mr. Layton, 61, had already been fighting prostate cancer. The news of this most recent turn of health is a devastating blow not only to him personally but to a party that is settling into the job of Official Opposition for the first time in its 50-year history - a stunning political achievement that most New Democrats lay at the feet of the man who has been their Leader for the past eight years.
He began experiencing stiffness and pain during the final days of the spring parliamentary session and underwent a battery of tests at Toronto's Princess Margaret Hospital. After the results came back last week, Mr. Layton spent several days consulting with his family and his chief of staff, Anne McGrath, before deciding to allow an interim leader to take charge, if only for a couple of months.
Brian Topp, the president of the federal New Democrats, said he emerged from a canoe trip in Algonquin Park on Sunday to find dozens of messages on his cellphone, many of them marked urgent. He called Mr. Layton immediately.
By that time, "he was quite clear in his mind about what he wanted to do. He wanted the decks cleared so he could take on this new challenge," said Mr. Topp who, like other senior officials in his party, was clearly dispirited by the news.
But Mr. Layton stepped aside reluctantly. He believes he is just a step away from the Prime Minister's Office and does not want to be deterred, said Mr. Topp.
"He spent some time searching his heart asking himself what he wanted to do," he said. "He has told me quite clearly, 'I want to continue this work, I want to continue being the Leader, I want to continue doing the work we have been doing together of trying to replace the Conservative government with something better.'"
Mr. Layton's illness is a serious situation for the New Democrats and a tough test for the caucus, said Mr. Topp. "Life is unfair sometimes and this is very unfair," he said.
When he was diagnosed with prostate cancer a year and a half ago, the NDP Leader was forthcoming about the disease. This time he is keeping the exact nature of his affliction private. It is not prostate cancer, he said. He added that his prostate cancer is no longer a problem.
Princess Margaret Hospital released a statement saying only that "recently, new tumours were discovered which appear to be unrelated to the original cancer and Mr. Layton is now being treated for this cancer."
If this is an entirely new disease, his chances for recovery are better than if the prostate cancer has spread to other parts of his body.
Mr. Layton took over the party after it had slumped to 8.5 per cent of the popular vote in 2000. He set the NDP finances on solid footing as he increased the party's presence in the House.
The recent election took the New Democrats from a paltry 37 seats in the Commons to 103 - and shocked pundits with a jaw-dropping surge in Quebec, where the NDP had wallowed on the political fringe since its inception.
The NDP is relevant because of Mr. Layton, said former NDP spokesman Ian Capstick.
"This is what is most brutally and viscerally painful. This should be his time to make it a reality at a very critical time," Mr. Capstick said. "And instead his body has forced him to hand over the reins."
The news of Mr. Layton's illness brought words of support and concern from all parts of the political spectrum. The social networking site Twitter immediately lit up with messages from well-wishers in every party.
Prime Minister Stephen Harper issued a statement saying he was deeply saddened and wished his political opponent a speedy recovery. "We are all heartened by Jack's strength and tireless determination, which with Mr. Layton will never be in short supply," said Mr. Harper.
Liberal Leader Bob Rae said he knows Mr. Layton to be a resilient man. "I hope," said Mr. Rae, "that taking a break from politics will give him the time and energy he needs to make a full recovery and continue his contributions to public life."
Mr. Layton recommended that Hull-Aylmer MP Nycole Turmel, a former union leader who was unanimously elected caucus chair, take over as temporary leader of the party until he can return. The caucus and the federal council will also be consulted before a final decision is made.
In choosing Ms. Turmel, a rookie, Mr. Layton bypassed both of his deputy leaders - Libby Davies, a long-time Vancouver MP; and Thomas Mulcair, the man who established a beachhead for the NDP in Quebec by winning a Montreal seat in a by-election in 2007.
Mr. Layton's health concerns were always visible during the spring election campaign, as he carried a cane to act as support after breaking his hip in late February. By late April, near the end of the campaign, the cane, which he described as a little extra security rather than a strictly needed support, seemed more a symbol of triumph than pain: He thrust it over his head in speeches to chanting crowds.
"People that go through serious illness, you can either go one way or the other. You can either become despondent about it all," Mr. Layton told The Globe and Mail at the time. "Or it kind of rejuvenates you, makes you focus on what's important,"
With reports from Lisa Priest in Toronto
and The Canadian Press