Earlier Detection for High-risk Women

Women who have a family history of breast cancer are at increased risk for developing the disease, and at a younger age than the general population. A new study in the European Journal of Cancer reports on the benefits of early screening for these high-risk women.

Researchers began surveillance of 678 women with a family history of breast cancer but no symptoms of the disease. A total of 294 women who were deemed to be at moderate risk for breast cancer were screened with an annual physical examination and annual mammography starting five years before the earliest onset of disease in the patient's family. Another 384 women judged to be at high risk were screened with physical examination every six months and annual mammography starting at age 25. Magnetic resonance imaging (MRI) was also performed for 109 women in the high-risk group with dense breast tissue. All the women were instructed in how to perform breast self-examinations and encouraged to do so monthly.

Twenty-six breast cancers were detected in the women under surveillance. During the study period, 24 breast cancers were found in patients with a family history who had symptoms of the disease and were not under surveillance. The breast cancers detected under surveillance were found at a significantly earlier stage than those identified in non-surveillance patients. Further, the stage of detection was just as favorable for women younger or equal to age 50 as it was for those over age 50.

The authors conclude that starting screening of women with a high risk for breast cancer years before the youngest age of onset in the family may result in high detection rates.

Source: European Journal of Cancer. March 2000. Volume 36, pp. 514-519

Extent of Surgery and Breast Cancer Recurrence

A study published in the Journal of Clinical Oncology finds a strong association between the extent of surgery for breast cancer and the likelihood of breast cancer recurrence after eight years.

Data for 533 patients with early breast cancer (stage I or II) were included in the study. Each patient underwent lumpectomy (surgical removal of the tumor and surrounding tissue) followed by radiation therapy. Researchers analyzed the surgical margins of the lumpectomy surgery and classified the margins into one of four categories. The margin was termed "negative" if there were no tumor cells and more than 1 mm of normal tissue was removed around the tumor, while a "close" margin showed no tumor cells but less than 1 mm of normal tissue. "Focally positive" margins had microscopic evidence of tumor cells, and "extensively positive" margins revealed tumor cells in several areas.

After eight years, 7% of patients with "negative" and "close" margins had a local breast cancer recurrence. Patients with "focally positive" margins had a local recurrence rate of 14%, and those with "extensively positive" margins had a recurrence rate of 27%.

Forty-five of the patients with "focally positive" margins received chemotherapy. Among these patients, the local recurrence rate was 7%. The authors suggest that women with focally positive margins who undergo chemotherapy are good candidates for breast-conserving surgery. However, patients with "extensively positive" margins should undergo further surgery--either removal of more tissue or mastectomy (removal of the entire breast).

Source: Journal of Clinical Oncology. April 8, 2000. Volume 18, No. 8, pp. 1668-1675

Pregnancy and Breast Cancer Risk

It is known that early age at first pregnancy offers some protection against the development of breast cancer. One of the largest studies ever published on this topic confirms this finding and offers new information about the effect of subsequent pregnancies. The study was published in the American Journal of Epidemiology.

Researchers analyzed data for 9,891 women aged 20 to 79 years with breast cancer and 12,271 control women of similar ages who were randomly selected. Complete information on reproductive history and a number of risk factors for breast cancer was available for the women with breast cancer; telephone interviews were conducted for the women in the control group to obtain this information.

Even when other risk factors for breast cancer were taken into account, an early age at first full-term pregnancy was still inversely related to breast cancer risk. Age at subsequent full-term pregnancies did not affect this finding. Further, the study found that closer birth spacing is associated with a reduced breast cancer risk.

Age at other pregnancies after the first did not significantly affect breast cancer risk. This finding supports the theory that changes in mammary cells that take place with a first pregnancy, making them less susceptible to abnormal growth, are sustained throughout life.

Researchers believe that pregnancy causes maturation of mammary cells that confers protection against breast cancer. In addition, pregnancy causes long-term hormonal changes that may offer further protection.

Source: American Journal of Epidemiology. April 1, 2000. Volume 151, No. 7, pp. 715-722

Older Women With Breast Cancer

A woman's risk for breast cancer increases with age. As the overall population of the U.S. ages, the number of elderly women with breast cancer is increasing. A recent study seeks to understand the characteristics of the disease, typical treatment, and survival of older women with invasive breast cancer.

Researchers analyzed data for breast cancer patients aged 55 and older from two large databases--35,154 in one group and 171,424 in the other. They found that increasing age at diagnosis of breast cancer was associated with more favorable tumor characteristics that generally point to a better outcome.

Older women were less likely than younger women to receive chemotherapy and radiation therapy. They were also less likely to undergo extensive surgery than younger patients. However, they were just as likely as younger patients to receive hormonal therapy, such as tamoxifen.

Survival of breast cancer patients was compared with survival of age-matched women in the general population. The women with breast cancer had similar survival rates to women in the general population, regardless of disease status. In older patients with small tumors or no cancer involvement of the lymph nodes, survival was almost identical to that of the population in general.

The similarity in survival of breast cancer patients with the general population might be related to the increased medical attention that breast cancer patients receive. Other serious medical problems, such as hypertension and diabetes, may be more often identified and treated in breast cancer patients. This could reduce the number of deaths attributed to medical problems other than breast cancer.

The authors conclude that the favorable outcome of older women with breast cancer should be taken into consideration when decisions regarding treatment are made. Source: Journal of the National Cancer Institute. April 5, 2000. Volume 92, No. 7, pp. 550-556

Mortality Among Women with DCIS

Researchers report that women diagnosed with ductal carcinoma in situ (DCIS), breast cancer detected at a very early stage, have very low breast cancer mortality rates. Findings were published in the Archives of Internal Medicine.

The analysis included 7,072 black and white women with DCIS who were age 40 and older. The study authors compared death rates for women diagnosed from 1978 to 1983, before mammography was commonly used for breast cancer screening, and women diagnosed from 1984 to 1989, when screening mammography became common. Of those who were diagnosed in the earlier time period, 1.5% died of breast cancer within five years and 3.4% within 10 years. In the later time period, 0.7% died of breast cancer within five years and 1.9% within 10 years. The researchers note that fewer women died of breast cancer in the later time period despite decreasing use of mastectomy (removal of the breast) to treat DCIS.

Women diagnosed with DCIS between 1984 and 1989 were less likely than women in the general population to have died of cardiovascular disease or all causes of death combined. The authors speculate that women diagnosed with DCIS may represent a subgroup of the population that is healthy overall. Most cases of DCIS are detected with mammography, and women who have regular mammography screening may have healthier lifestyles than women who do not. Further, women who have mammography screening may be more likely to use hormone replacement therapy, which has been associated with a reduced risk of cardiovascular disease.

Source: Archives of Internal Medicine. April 10, 2000. Volume 160, No. 7, pp. 953-958

[Table of Contents] [Archived Issues / Search] [The Breast Center]