Mammography, the X-ray of the breast, can detect breast cancer when it can still be cured -- virtually 100 percent, the experts say, by simply removing it, with no further treatment. And you know how doctors are -- they don't say 100 percent unless it's pretty certain that it's 100 percent.

Mammography can picture a lesion only a few millimeters across, deep inside even the most ample breast, long before it can be felt by a physician or detected by the women herself. (By that time, it may be too late to prevent the cancer's spread.)

New equipment, used exclusively for breast examination, produces so little radiation that, said Dr. Dixie Melillo, the risk associated with the mammogram itself is "comparable to smoking three quarters of one cigarette, of traveling 400 miles by air, of living 20 minutes as a man of 60, with all his accumulated risks."

Melillo is a surgeon at Pasadena Bayshore Medical Center in Houston specializing in breast cancer. She is as active in its prevention as its treatment. She testified last week at hearings chaired by Sens. Barbara A. Mikulski (D-Md.) and Brock Adams (D-Wash.) in support of Mikulski's legislation that would extend Medicare coverage to routine screening mammograms, a procedure that can cost as much as $200.

Currently, Medicare pays for mammograms only when they are used to diagnose something already large enough to be suspicious. ::

"Only God could feel that little thing," my surgeon, Dr. Jerome Canter, told me three months ago after looking at the late autumn mammogram I have every year.

And although this "thing's" size (about 4 millimeters) suggested that even if it were something, even if it were malignant, it still probably would be nothing. I spent the ensuing weeks acutely conscious that it was there, deep in my right breast. I felt it burning, growing in my mind's eye. It was always at the edge of my consciousness, if not right smack in the middle.

Canter and Dr. Leonard M. Glassman, chairman of the radiology department at Columbia Hospital for Women, took the mammogram -- my first on the latest state-of-the-art equipment -- along with the mammograms for the last 10 years or so and "enhanced" the older ones electronically.

Whatever it was, had been there as far back as 1982 but didn't show up on the older, unenhanced mammograms. The new look at the old films showed that it had grown somewhat between 1982 and 1985 but had not changed since then.

That was not an indication that it was or was not cancer. Breast cancers tend to be very slow growing, especially as a woman grows older. But as a woman grows older, the risk of breast cancer increases rapidly. I was growing older. ::

As Sen. Mikulski noted in her opening remarks at the hearing of the Senate Labor and Human Services Committee Thursday, of the 40,000 women who died of breast cancer last year, 28,000 were over 65. Of the approximately 130,000 cases of breast cancer reported in 1987, half were in women over 65. The American Cancer Society estimates that there will be 142,000 new cases this year.

Dr. Charles R. Smart, chief of the early detection branch of the National Cancer Institute, told the senators: "If modern mammography were applied broadly in the United States to the population of women over 40, there is good reason to believe that mortality from breast cancer would decrease by 30 to 40 percent, and where applied to older age groups the benefits would be even greater."

There are some 16 million American women over 65. Yet only a fraction of their cancers are discovered in time for a cure rate better than 50-50.

"The object of screening for breast cancer is to discover those among the apparently well who are in fact suffering from disease," testified Dr. Philip Strax, oncologist and radiologist at the University of Miami School of Medicine and author of the pioneering study that showed in the 1960s that routine screening could reduce breast cancer mortality.

"It is bizarre and ironic," testified Rose Kushner, medical consumer activist and breast cancer survivor, "that the Medicare program, specifically designed to improve the health and prolong the lives of our country's senior citizens . . . fails to cover the cost of mammography to detect this potentially fatal disease when it is early and more likely to be cured."

And actress Jill Ireland said, "It seems to be a social crime . . . that women who lack funds are being denied the chance to be spared from suffering." Ireland, 51, is the author of "Life Wish," an account of her life and loves as well as her own 4-year-old battle with breast cancer. She is married to actor Charles Bronson. She had a radical mastectomy in 1984 and a long, painful course of chemotherapy. Her cancer had already begun to spread when it was discovered on a routine mammogram. Still, she credits that mammogram with saving her life. ::

The hearing on the Mikulski bill was held two days after Dr. Canter excised the thing in my right breast -- it was too small to be characterized as a lump, or even a lesion. There was too little tissue to prepare a frozen section for a preliminary biopsy, so I sat and listened to the testimony last week with another 36 hours to go before I would find out that it wasn't cancerous.

By this time, the burning feeling was out of my mind's eye and into reality. I still had pain from the biopsy on Tuesday, and, of course, I imagined the worst.

The really good news about the so-called non-palpable (not able to be felt) kind of thing I had is its almost certain curability, no matter what it turns out to be. What hasn't quite caught up with this kind of early detection, however, is the procedure for its removal.

It's better than the old days -- better than 10 years ago when I'd had a lump removed. That entailed an overnight hospital stay, a general anesthetic and the paralyzing uncertainty as to whether or not I'd wake up with a mastectomy. Thanks in large part to Rose Kushner's persistence, that one-step procedure has been almost entirely abandoned.

And the current procedure is better than, say, a root canal on an abscessed tooth.

It is done in two stages in the course of a long day as an in-and-out patient, in my case at Columbia Hospital for Women. First there is another mammogram. Then a local anesthetic is administered. The radiologist looks at the mammogram picture as he inserts a thin needle into the breast, then threads a wire through the needle to the suspicious spot. The needle is removed; the wire remains as a signpost for the surgeon. It's not fun, but, believe it, an injection into the gum is far worse.

The actual surgery is also done under a local anesthetic and takes approximately 40 minutes. It's still better than a root canal, but it's getting closer. (You can talk back when it hurts, for one thing, not just grunt.) There are about a half-dozen stitches.

When it is over, the nurses at Columbia -- efficient, professional and solicitous -- wrap you in an extraordinarily comforting heated blanket. Other nurses proffer graham crackers and juice, equip you with an icebag for later, and you leave. ::

Columbia has new, more accurate equipment developed in Sweden that will in most cases make that surgery unnecessary. Cells will frequently be removable through a needle. Glassman has just returned from his training at the Karolinska Institute in Stockholm, but the equipment won't be ready for use for a another month or two. We could have waited, Dr. Canter said, but for the "apprehension factor."

If I didn't appreciate that before, I certainly did as I listened to the testimony on the Mikulski bill. Compared to the thousands of brave women with breast cancer, the little emotional angst and slight discomfort I faced last week was trivial. Yet I heard the testimony with new comprehension, a new and sharper and very personal empathy.

It is estimated that covering annual screening would cost Medicare an additional $150 million a year. Mikulski is suggesting they be covered every other year, reducing that cost somewhat.

"Many times" that amount, said activist Kushner, is spent every year to treat women with advanced breast cancer.