With recent media attention devoted to a few small studies on the possible negative effects of using Breast Cancer Diagnosed Earlier, Easier to Treat in Women on Hormone Replacement Therapy (dateline April 11, 2000) | Breast Health News | Imaginis - The Women's Health & Wellness Resource Network

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Breast Cancer Diagnosed Earlier, Easier to Treat in Women on Hormone Replacement Therapy (dateline April 11, 2000)


With recent media attention devoted to a few small studies on the possible negative effects of using hormone replacement therapy (HRT), many women are questioning the benefits of HRT. While the majority of researchers believe that women who take HRT for a prolonged period of time (more than five years) could have a slightly higher risk for breast cancer , a new study published in the April issue of Obstetrics and Gynecology reveals that women who have been diagnosed with breast cancer while on HRT tend to be diagnosed earlier and have smaller, lower risk tumors than women with breast cancer who have not taken HRT. HRT is estrogen, synthetic progesterone, or a combination of the two hormones prescribed to many women to help alleviate several of the symptoms associated with menopause (such as hot flashes, vaginal dryness, and insomnia) and to prevent or treat osteoporosis, a degenerative bone disease.

The study compared 47 women who had developed breast cancer while on HRT with 455 post-menopausal women who had never taken HRT. According to lead researcher Paul Tartter, MD breast cancer was detected in an early stage by mammography significantly more often among the women on HRT than in the women who had not taken HRT. Researchers attribute this to the fact that women on HRT are more likely to receive annual screening mammograms .

A breast cancer diagnosis was also confirmed with the biopsy of a non-palpable lump (one that cannot be felt by hand) more often in the women on HRT while the majority of diagnoses among women who had not taken HRT were made on palpable lumps. When physicians are able to diagnose breast cancer before a lump can be felt, the diagnosis is usually made early and the cancer can typically be treated successfully with minimally invasive procedures.

The researchers were also less likely to see breast cancer in the axillary (underarm) lymph nodes of women on HRT than in the women who had never taken HRT. Again, the researchers say this indicates an earlier breast cancer diagnosis in women on HRT (before the cancer has spread out of the breast) and higher chances that patients will respond well to treatment.

Summary of Results: Women Diagnosed with Breast Cancer

Women on HRT at time of diagnosis Women who had never taken HRT
  • 57% of cancers detected by mammogram (earlier detection)
  • 52% of lumps biopsied were non-palpable (unable to be felt by hand, signals earlier diagnosis)
  • smaller invasive tumors (1.4 cm)
  • 19% of diagnoses involved lymph nodes
  • 82% of tumors were estrogen receptor-positive (could respond better to certain treatments, such as tamoxifen)
  • 67% of tumors were progesterone receptor-positive (could respond better to certain treatments)
  • 89% of tumors were small enough that breast conserving therapy (lumpectomy) could be performed instead of mastectomy
  • 38% of cancers detected by mammogram
  • 69% of lumps biopsied were palpable (felt by hand, signals later diagnosis than non-palpable)
  • larger invasive tumors (2.1 cm)
  • 29% of diagnoses involved lymph nodes
  • 65% of tumors were estrogen receptor-positive (could respond better to certain treatments, such as tamoxifen)
  • 50% of tumors were progesterone receptor-positive (could respond better to certain treatments)
  • 69% of tumors were small enough that breast conserving therapy (lumpectomy) could be performed instead of mastectomy

*This study is published in the April 2000 issue of Obstetrics and Gynecology

More estrogen-receptor (ER) and progesterone-receptor (PR) positive tumors were also found in women on HRT. ER and PR positive tumors tend to respond better to certain treatments, such as the drug tamoxifen.

Because most of the tumors in the women on HRT were small, the majority of women on HRT could be treated with breast conserving therapy ( lumpectomy), radiation therapy , and/or tamoxifen.  Women who had not used HRT were more likely to need mastectomy (breast removal) or chemotherapy. The researchers note that the five-year survival rate among the two groups of women did not differ significantly. Previous studies have shown that women on HRT are less likely to die of breast cancer than women who have never taken HRT.

Dr. Tartter noted that some of his patients who have survived breast cancer continue to take HRT to lessen menopausal symptoms and that none of them have experienced a recurrence (return) of breast cancer. Research has also shown that HRT may help with Alzheimer’s disease , type II diabetes (adult onset), colon cancer, urinary incontinence, and heart disease . HRT is also approved by the U.S. Food and Drug Administration (FDA) to prevent and treat osteoporosis, a degenerative bone disease affecting one in three women over age 50.

Recently, a handful of new studies have shown that HRT may increase breast cancer risk and may not prevent heart disease as originally thought. The results of these studies need to be confirmed in additional studies with a larger number of participants.

It is estimated that only 10% to 15% of menopausal women take HRT. According to physicians, the two most common reasons why women do not take HRT to alleviate menopausal symptoms are:

  • they do not want to menstruate again
  • they are afraid they will develop breast cancer

Women who are considering taking HRT should discuss the benefits and possible side effects and risks of the therapy with their physicians. Possible side effects of HRT include:

  • bloating
  • nausea
  • breast tenderness (during the first three to four months of treatment)
  • vaginal bleeding
  • fluid retention
  • weight gain
  • depression
  • possible increased risk for breast cancer (if taken for more than five years)

Interestingly, the majority of women who use HRT are women physicians or wives of physicians.