More than 200,000 women are diagnosed with breast cancer every year in the US. Yet, in one out of 10 of these women, doctors may not find the cancer as early as they could, according to a report in the June 24 Archives of Internal Medicine (Vol. 162:1343-1358).

This new research was reported by William Goodson III, MD, and Dan Moore II, PhD, from the California Pacific Medical Research Institute. Goodson and Moore looked at the reasons for the delayed breast cancer diagnosis for 42 out of 435 women referred to a single surgeon for treatment from January 1992 through December 1999.

The authors looked at the women's medical records to find out if their breast cancer could have been diagnosed earlier. More importantly, the doctors looked at the reasons for the delays, so the women's experience could be shared with others to help them avoid similar problems.

As it turned out, looking at all the women in the study, the delays did not affect the size of their cancers, the presence or absence of cancer in the lymph nodes, or the types of surgery performed.

The reasons for the delays were many. Sometimes the doctor found a breast mass on an exam, but told the woman it was benign without performing a biopsy of the mass.

Other times, a fine needle aspiration (FNA) of the mass didn't reveal any cancer cells, while a follow-up aspiration of the same mass was positive for cancer. A fine needle aspiration is a simple test in which a thin needle is passed into the breast mass, and a sample of breast cells is removed. It can be done in a doctor's office.

There were other reasons for the delays in diagnosing breast cancer, including slides of breast cancer cells that were misread as benign when cancer was present, and mammograms that were read as negative for cancer, when in fact cancer was present.

For 9% of the women, there was an avoidable delay in the diagnosis of their breast cancer, according to the authors. Almost 60% of these women had delays greater than six months.

One common reason for delay was the doctor reassured the patient that the lump was benign without performing some type of biopsy, and it actually was cancer. Another common problem was the lack of experience in the doctor who performed the FNA. Without experience, a doctor might either not get cells from the mass or miss the cancer cells in the mass altogether.

Another problem was a benign mammography report — when a mass that could be felt turned out to be cancerous even though it didn't show on the mammogram. This is not surprising, experts say, because not all breast cancers can be seen on a mammogram. Hormone therapy in postmenopausal women also contributed to delay, probably because of the effects of the hormones on the breast tissue.

"Despite widespread screening mammography, inappropriate reassurance that a palpable (can be felt with the hand) mass is benign, without biopsy, remains the leading cause of physician delayed diagnosis of breast cancer, affecting 5% of patients in our series," noted the authors.

There also was a suggestion that doctors may pay less attention to breast masses women find on their own through self examination than those found by doctors or others who perform breast exams.

However, in most doctors' experience, women who do self-exams tend to find many masses that require evaluation and turn out to be benign. As a result, doctors place less emphasis on a self-diagnosed breast mass.

The authors said, "We believe that most delayed diagnoses reflect not failures by individuals, but, rather, the overall inadequacy of practices that are accepted, despite the fact that they fail even in experienced hands.

"Reducing delay will require collective changes in all clinicians' perception of whether to interpret CBE (clinical breast examination performed by a trained medical professional), the reliability of mammography, whether to demand that tests like FNA be performed well or simply performed, and possibly how to interpret the secondary effects of HRT (hormone replacement therapy)."

This study reminds doctors that it is important for them to take changes in the breast very seriously — and especially when a woman or a man is concerned about something they have found on their own.