The phone rang at her home in Arlington, and the caller identified himself as a doctor. Was the lady's husband at home, please?

He's out of town on business, she said. Is there something I can do?

Well, the doctor said, hesitantly, it's about the test results. . . .

What test results?

Gee, said the doctor, I'd really like to tell you, but I can't. However, I can tell you that your husband was in here two weeks ago to have me check on a problem he was having.

Alarmed, the woman demanded that the doctor give her the bad news, if there was any.

Well, said the doctor, I don't usually do this, but since you're his wife, I think I can tell you. Your husband is dying of cancer of the prostate.

The woman had no reason to disbelieve the voice on the phone, and although she was extremely upset, she decided not to discuss the news with her husband until he returned home and they could deal with it face to face. For two days, she lived with the kind of mental strain that most of us can only imagine. As soon as she saw her husband, the woman told him she had gotten the awful news from the doctor.

"What doctor?" said the husband.

Followed soon by: "What tests?"

And: "What test results?"

It was all a monstrous fraud.

The couple called the Arlington County Police Department, which is investigating. But detectives there and elsewhere in the area tell me that fake doctor schemes are a growing problem. In Arlington County alone, detectives say, eight cases extremely similar to the one above have been reported since last spring.

"They're a new kind of obscene phone call," said one detective, who asked not to be quoted by name. "There's always some new way for a sickie to get his kicks, it looks like."

Frank Ferraraccio, executive vice president of the Medical Society of the District of Columbia, says his organization has not heard of such medi-fraud before. But he says it's easy to tell who's a doctor in these circumstances and who isn't:

* If a doctor doesn't know a wife well, he will not give her the results of tests performed on her husband, and he may not do so even if he does know her well, Ferraraccio says.

* If a person indicates that he or she doesn't know that tests were performed on his or her spouse, a doctor would not give out the results under any circumstances, Ferraraccio says.

* It's almost unheard of for a doctor to deliver such devastating news over the phone, either to victim or spouse. The usual scenario, says Ferraraccio, is for the doctor to tell the victim that he has the test results, and could you please come into the office to discuss them with me?

If you get a phone call from a "doctor" who seems a little too eager to pass along bad news, he's probably a phony. But you should alert the police in any case. It's quite possible that one nut is making all these calls. The sooner a judge locks him far from a phone and throws away the key, the better.