IT'S ALWAYS possible to come up with a new variation on an old theme. Hospital dramas are so commonplace, they all seem to be done by the numbers. But ''The Doctor'' avoids that pitfall. This hospital drama is continually absorbing. It threatens, occasionally, to wallow in sentimentality but never does.
The film, starring William Hurt, was directed and produced by Randa Haines, who directed Hurt in ''Children of a Lesser God,'' and Laura Ziskin, who produced ''Pretty Woman'' and ''What About Bob?''
We can forgive Ziskin for "What About Bob"; ''The Doctor,'' which opens at area theaters today, is her redemption.
William Hurt plays the bright, professional, but remote heart surgeon Jack MacKee, who listens to rock 'n' roll as he works and jokes a lot.
He is almost arrogant, and would be completely so if he didn't have that sense of humor. His attitude changes, however, when he discovers that he has a malignant growth on his vocal chords.
When he visits the hospital at which he has worked, he is treated vTC like other patients, and he doesn't like it. He also doesn't like to think that this is the way hospitals are run. The experience causes him to reassess his position in the medical world.
He has a wife, but they have a now-you-see-me, now-you-don't arrangement. They're in love, but he gives more to his job than he does to her.
Christine Lahti is the doctor's wife, a patient and giving woman. Elizabeth Perkins is a woman who meets the doctor as both sit in a waiting room. She has a brain tumor.
It is illness that brings the two together, and thankfully, the situation doesn't go beyond this. That would have taken the film into an unnecessary area. These two are good friends, nothing more, and even the doctor's wife understands. The wife would prefer that her husband find solace in her rather than another woman, but she understands.
Understands to a point, that is. There is an end to the woman's patience, but this film is not a downer. There is a happy enough ending to "The Doctor."
The film plays very much like ''Regarding Henry.'' Both films are about professionals who are allowed the opportunity to change their lives.
''The Doctor'' is based on ''A Taste of My Own Medicine,'' written by Ed Rosenbaum, a physician. Haines has artfully directed the film, which takes place in the cold, steely innards of a new, high-tech hospitals.
Mandy Patinkin is one of the doctor's colleagues who is involved in a malpractice lawsuit. Adam Arkin is another colleague who suffers the satirical barbs that MacKee sends his way. He is there, however, when MacKee needs him.
''The Doctor'' is primarily about the efficient but unfeeling medical professional, but it is also about the hospital world, the mistakes, the indifference and bad judgment calls.
Some of this is excusable because it is human. Some of it is not, and that's what the film says, subtlely.
Hurt, Lahti and Perkins give excellent performances. Look for Academy Award nominations here.
''The Doctor'' **** An efficient but remote heart surgeon finds himself on the other side of the stethoscope when he is told he has cancer of the vocal chords.
CAST: William Hurt, Christine Lahti, Mandy Patinkin, Elizabeth Perkins, Adam Arkin
DIRECTOR: Randa Haines
RATING: PG-13 (language)
RUNNING TIME: 123 minutes