WASHINGTON (AP) - Potential presidential candidate Fred Thompson, known to millions of "Law & Order" viewers as a gruff district attorney, revealed on Wednesday that he was diagnosed with non-Hodgkin's lymphoma, a form of cancer, nearly three years ago.
Thompson, 64, said he is in remission, and never even felt ill, from a type of lymphoma that is very slow-growing and probably not life-threatening. The Tennessee Republican was prompted to make the disclosure on the Fox News Channel and ABC Radio because he is thinking about running for president.
"I know it's not a big deal, as far as my health is concerned, as much as a person can know about things like that," Thompson said.
"But other people have the right to look at it and weigh in, and I have a need to factor that into my decision in terms of the reaction that I get about it," he said.
Thompson's physician said he encourages such patients not to limit their activities, even if that includes a bid for the White House.
"They can lead a normal life. They can travel. They can work. They can possibly be president of the United States," Dr. Bruce Cheson, hematology chief at Georgetown University Hospital, told reporters at an afternoon news conference.
Former Senate Majority Leader Bill Frist, a heart surgeon who abandoned his own plans to seek the presidency, said Thompson's disclosure "indicates his seriousness as a potential candidate."
On his Web site, Frist, also a former Tennessee senator, urged supporters to post statements encouraging Thompson to run.
Thompson, who plays district attorney Arthur Branch on NBC's long-running drama "Law and Order," was diagnosed after a doctor found "a little bump in my neck" during a routine physical about 2 1/2 years ago, he said.
The bump, located under his left jaw, turned out to be an indolent form of non-Hodgkin's lymphoma, one that tends to respond well to treatment, he said.
Lymphoma is an immune-system cancer that strikes more than 71,000 people, killing more than 19,000 each year in the United States. Overall, the five-year survival rate for the non-Hodgkin's group of lymphomas is 63 percent, according to the American Cancer Society.
But patients with indolent lymphoma tend to live many years.
"The textbook answer for average survival in low-grade lymphoma is 10 years. I always tell patients that was for diagnoses 10 to 15 years ago," said Dr. Mitchell Smith, lymphoma chief at Fox Chase Cancer Center in Philadelphia.
The former senator said his cancer is "literally irrelevant in terms of my daily routine." He sometimes has 14-hour days, working out three times a week, often filling in for ABC Radio broadcaster Paul Harvey in the morning and taping "Law & Order" in the afternoon.
"So my life goes on as normal," he said. "Nobody knows about the future, of course, but as much as the doctors can tell ... it should not be a factor."
Thompson told Fox interviewer Neil Cavuto, who has battled Hodgkin's disease in the past and has multiple sclerosis, he has many friends in politics, some running for president, who have successfully dealt with cancer.
Republican Sen. John McCain has had three bouts with melanoma, the most aggressive form of skin cancer, and 2008 rival Rudy Giuliani battled prostate cancer. John Kerry, the 2004 Democratic nominee, and Bob Dole, the 1996 GOP nominee, also had prostate cancer.
And Democrat Paul Tsongas ran for president in 1992, six years after lymphoma forced an end to his Senate career. Tsongas had undergone a radical bone marrow transplant and later, after his disease recurred, died from a complication related to treatment.
Also, just weeks ago, Elizabeth Edwards, wife of Democratic presidential candidate John Edwards, announced that her cancer had returned, and White House spokesman Tony Snow recently had surgery for cancer that spread to his liver.
After being diagnosed, Thompson received radiation first. But then doctors noticed growth of additional lymph nodes and gave him Rituxan, the first in a new generation of drugs that over the last decade has revolutionized lymphoma care. Rituxan is made of monoclonal antibodies, cells engineered to hunt down the cancer - by recognizing an antigen on its surface - and kill it without doing the harm to surrounding tissue that chemotherapy would.
"Some lymphomas are very aggressive, but people with slow-growing types, like Senator Thompson's, more often die from natural causes associated with old age, rather than from the disease," said Cheson, who is examining him every few months to ensure that he remains in remission.
Indolent forms like Thompson's, which is known as "marginal zone lymphoma," are not curable. But they're easier to push into remission, repeatedly if need be, with doctors treating it as a chronic disease, Smith said.
Thompson was elected to the Senate in 1994 to fill the seat of Al Gore and easily won re-election in 1996, but after his daughter died of a heart attack in 2002, he announced he would not seek another term.
Thompson, who is divorced, married his second wife, Jeri Kehn, in 2002. Thompson has two young children at home, including a 4-month-old son, and has two older children.