"This is a very, very, very, good sign," says throat cancer expert Gady Har-El, MD, chair of head and neck surgery at New York's Lenox Hill Hospital. Har-El is not involved in Douglas's treatment.
Based on details Douglas made public in an interview with Today show host Matt Lauer, Har-El says Douglas has made the first step on the road to recovery: what doctors call a "complete response" to treatment.
"Obviously Mr. Douglas is not completely out of the woods because there is a chance of tumor recurrence," Har-El tells WebMD. "As time goes by, his odds get better. If he has no evidence of disease in the next three years, his chances of cure are extremely high."
As Douglas told Lauer, he will get physical exams every month. Every six to 12 months, the scans will be repeated.
Douglas appears to have had a large tumor -- too large to remove by surgery. His throat cancer, oropharyngeal cancer, had reached a dangerously late stage.
Unfortunately, oropharyngeal cancer is becoming more and more common. Smoking, and, to a lesser extent, drinking are risk factors for the disease. But the disease also is caused by HPV, the sexually transmitted virus that causes genital warts and cervical cancer. HPV-related oropharyngeal cancer, Har-El says, tends to be more readily curable.
The bad news, Douglas says, is that his salivary glands aren't working properly. Radiation treatment for oropharyngeal cancer kills the tumor but also blasts the salivary glands.
Har-El says Douglas' salivary-gland function likely will improve over time, but that it may never fully recover. Most people, he says, don't fully appreciate how difficult it is to be unable to salivate normally.
"How does it feel to swallow without saliva? Take a bagel, put butter on it, then dip it in beach sand and try to eat it," Har-El says. "It is very rough and has effects on the teeth, on swallowing, and on speech. It does get better with time, but in most cases doesn't go back to full recovery."