MEDICATIONS: HORMONE REPLACEMENT THERAPY DOES NOT APPEAR TO INFLUENCE BREAST CANCER DETECTION

September 18, 2002 — Taking hormone replacement therapy (HRT), does not diminish the ability to detect breast cancers or affect clinical outcomes for patients with breast cancer, according to an article published in the September issue of The Archives of Surgery, a journal of the American Medical Association.

Rodney Pommier, M.D., of Oregon Health and Sciences University in Portland, Oregon and colleagues looked at the records of 292 postmenopausal patients with breast cancer to determine whether taking HRT was associated with the detection of breast cancer using palpation (feeling for lumps) and mammography, and clinical outcome.

According to background information in the article, previous studies have indicated that taking HRT can increase the risk of developing breast cancer. Because HRT increases the density of breast tissue, researchers believe that breast cancers may be harder to detect in patients taking HRT, and that their tumors may be in more advanced stages when detected. Following this line of reasoning, breast cancers of patients taking HRT will more likely be detected though palpation when they are big enough to feel (after possibly being missed by mammography).

Pommier et al performed a retrospective study of the records of 292 postmenopausal patients diagnosed with breast cancer at Oregon Health and Science University (Portland, Oregon) between March 1994 and January 2002. One hundred forty-four women had received HRT at the time of diagnosis and 148 women had not received HRT. The average patient age was 66 years old and there was no significant difference in age at diagnosis between the two groups.

The researchers found that 84 HRT users' cancers were detected by mammography and 60 were detected by palpation. Among non-users, 63 cancers were detected by mammography and 85 were detected by palpation.

Twenty-three patients using HRT were diagnosed with ductal carcinoma in situ (DCIS) (an early form of breast cancer), and 14 were diagnosed with DCIS in the non-user group.

There was no significant differences in tumor size, number of positive nodes or incidence of stage IV tumors based on HRT status. The six-year survival rate for patients with mammographically detected tumors was 94 percent, compared with 78 percent whose tumors were detected by palpation.

"In this study, HRT had only beneficial and no discernable harmful effects on breast cancer detection or outcome. Fears of decreased mammographic detection of breast cancer in patients who received HRT prior to diagnosis were not substantiated in this study. In addition, concern that HRT induces aggressive tumor progression was refuted by improved survival rates. It is plausible that the beneficial effects of HRT on breast cancer could outweigh its reported risk of a slight increase in the incidence of the disease," write the authors.