When Michael Douglas announced last August that he was being treated for late-stage throat cancer, many fans took that to mean he'd received a death sentence. But the Oscar-winning actor told TODAY's Matt Lauer that he's got cancer "beat."
An upbeat but rather thin Douglas said heavy doses of chemotherapy and radiation have vanquished his tumor.
"It’s great news that they can’t see any cancer," said Dr. Bert W. O’Malley, a professor and chairman of the department of otorhinolaryngology-head and neck surgery at the University of Pennsylvania Medical Center. "He’s over the first hurdle. The next is what happens over the next three years."
Three years is considered the benchmark for deeming such a patient truly cancer-free.
These days, the outcomes for patients like Douglas can be very good, doctors report. But it often depends on the type of tumor, noted O’Malley.
If the tumor was caused by infection with the human papillomavirus (HPV), then the odds are much better than they would be if it were related to other factors, such as smoking and alcohol consumption, O’Malley said, explaining that the HPV virus that causes some throat cancers is the same one that has been linked to cervical cancer in women.
While the overall survival rate for patients with late-stage throat cancers is about 50 percent to 60 percent, that number rises to 80 percent in patients with HPV-related tumors, O’Malley said.
It's not clear which form of the cancer, Douglas, 66, has been battling. HPV-related tumors make up about 40 percent to 45 percent of throat cancers, said Dr. Salvatore Caruana, director of the division of head and neck surgery at New York-Presbyterian/Columbia Medical Center. And many of the cancers that occur in the tonsils or on the tongue are related to HPV, he added.
No one knows exactly why HPV-related tumors are easier to cure than others, Caruana said. But experts think it’s because the cancer targets a small set of genes, while many genes are damaged by the other types of throat cancer, he said.
Ultimately, Douglas’ situation may be pretty typical, experts said.
Don't miss these Health stories
More women opting for preventive mastectomy - but should they be?
- Larry Page's damaged vocal cords: Treatment comes with trade-offs
- Report questioning salt guidelines riles heart experts
- CDC: 2012 was deadliest year for West Nile in US
- What stresses moms most? Themselves, survey says
- More women opting for preventive mastectomy - but should they be?
There was a big brouhaha over the fact that Douglas’ cancer wasn’t diagnosed till it hit stage IV, but that’s a very common scenario, said Dr. Robert Ferris, a professor of otolaryngology and chief of head and neck surgery at the University of Pittsburgh Medical Center.
“The symptoms can be very non specific — maybe just a little trouble swallowing,” Ferris said. “Tumors like this can get pretty big, up to 2 to 3 inches, before they are detected because they grow at the base of the tongue near the throat.”
And because this part of the tongue is normally lumpy, people often aren’t aware of the tumor for a long while, Ferris said.
Even with the tumor gone, recurrence is a major concern so it’s important for Douglas to have regular check ups, experts said. Around 85 percent to 90 percent of recurrences are within the first two years, Ferris said. By three years, that number goes up to 90 to 99 percent.
“That’s why each anniversary is a very momentous sort of thing for head and neck cancer patients,” Ferris said.
For patients who do make it past that all important third anniversary, there may still be some unpleasant long term side-effects to deal with, experts said.
Douglas told TODAY that he's been "eating like a pig" to try to put back on the 32 pounds he lost from radiation treatments.
Douglas' famous voice still sounds strong, but he explained his salivary ducts have been shut down as result of the radiation — and may remain out of commission for a year or two — so he struggles with a very dry mouth.
As a result of the anti-cancer treatments, people can completely lose the ability to swallow and eventually have to depend on a feeding tube for nourishment, Ferris said.
“Swallowing is one of those daily activities we take for granted,” he added.
© 2013 msnbc.com. Reprints