The 65-year-old actor who is the son of Hollywood icon Kirk Douglas will undergo an eight-week course of chemotherapy and radiotherapy and had said that he is optimistic of a full recovery.
But sources close to the family say that the actor has a locally advanced cancerous growth and if the 'synchronous' therapy does not work out, he will have to undergo surgery, which would leave him with a changed voice, or no voice at all, reported Daily Mail online.
The 'Wall Street' star had decided to consult a doctor some weeks ago after his voice became hoarser and he started having trouble in swallowing.
The actor who was a smoker for decades, will begin the treatment in New York and reports indicate it is due to start this week.
Douglas's camp has let it be known that his doctors think that, although the situation is frightening, he will make a full recovery. Douglas himself released a statement saying, "I am very optimistic".
There is also no word yet on how the treatment will affect his work schedule, as Douglas has a lot on his plate, including promotion for his return to the character Gordon Gekko in 'Wall Street: Money Never Sleeps' which opens in September.
The actor has been enjoying a new high in a career that spanned four decades and cult films like 'Fatal Attraction', 'Basic Instinct' and 'Traffic'.
Douglas has been married since 2000 to the 'Mask of Zorro' actress Catherine Zeta-Jones and they have two young children together.