Hormone Replacement Therapy After Breast Cancer. Is it Safe? Part 1

“Psychologists have amply documented the human difficulty of changing our minds when the evidence says it is time to do so. The challenge for physicians is to recognize when we are stuck in an outdated paradigm, admit it, and move ahead.”

Estrogen Replacement Therapy (ERT) is Dangerous and Linked to Cancer

This controversial, polarizing statement affecting all women perpetuates today as the truth, but is it the truth?

The controversy is fueled by historical incorrect data interpretations and misleading assumptions.  For one week, I asked all women if they believed this statement to be true.  100% answered yes without hesitation.

Conversations about estrogen should always start with the study that rocked the world, the Women’s Health Initiative (WHI), with the media’s announcement in 2002 that hormone replacement therapy (HRT) caused increased breast cancer, cardiovascular disease and stroke. The results implanted fear into the minds of doctors and women concerning the dangerous use of estrogen still felt today.  HRT was abruptly discontinued, precipitating moderate to severe withdrawal effects.  HRT was no longer offered readily and may have led to increased health risks in patients who were being or would have been helped by hormone therapy.

Is the risk of HRT too great for Postmenopausal Breast Cancer Survivors?

The following blog is a summary of an article entitled, “Hormone Replacement Therapy After Breast Cancer: It Is Time, by medical oncologist, Avrum Bluming, MD. 

Dr Bluming was a clinical professor of medical oncology at University of Southern California.  He spent four years as a senior investigator for the National Cancer Institute.  For over 20 years, he has studied the benefits and risks of HRT administered to women with a history of breast cancer.  His co-authored book, Estrogen Matters is a must read for all women.  Dr Bluming is an avid supporter of the use of Premarin alone and in combination with natural progesterone.  He does not write or comment on the use of Bioidentical Estrogen Hormone Replacement (BHRT).

Breast Cancer Morbidity and Mortality in Perspective with Other Diseases and HRT

Among women experiencing perimenopause and menopause, estrogen replacement therapy (ERT) with Premarin has been reproducibly found to improve quality of life in 80% of women. No other treatment comes close to that of ERT in the great majority of patients and yet, this treatment is currently not widely offered to women even with no history of breast cancer.

Over 300,000 US women, or 1 out of 5 women, died of heart disease per year, equating to more than 7 times the number who die of breast cancer.  More women die of heart disease than breast cancer in every decade of life older than 40 years. Newly diagnosed breast cancer has an approximate cure rate of 90% and thus breast cancer survivors are at far greater risk of dying of heart disease than breast cancer.

More reliable than statins, estrogen decreases the risk of heart disease by 40-50%.

The number of US women who die each year due to breast cancer is similar to the number of women who die during the first year following hip fracture. Long-term ERT is more effective than bisphosphonates, zoledronate and denosumab, decreasing the risk of hip fracture by 30-50%.

The cure rate for Alzheimer’s is 0% and annually affects twice as many women as does breast cancer. While trials tracing the course of dementia are difficult to measure, estrogen is the most effective available preventive therapy for Alzheimer’s, with a 45-70% decreased risk in uncontrolled studies. This is not supported by all studies at this time.

ERT reduces the risk of and improves the prognosis of women with colon cancer. It has also been reported to reduce diabetes risk. Women on ERT have been projected to live an additional 3-4 years compared to those not on ERT.

Even “the study that rocked the world” reported women randomized to postmenopausal ERT were less likely to die of breast cancer and all causes after breast cancer diagnosis compared to the placebo group.  Read this statement again!

The Risks of ERT

One of the most cited risks of ERT is a twofold increased risk of venous thrombosis and pulmonary embolism (PE) in which most events occur within the first year of HRT and decrease thereafter. Given this risk, many have concluded the risks outweigh the benefits. Looking at the absolute numbers, in women aged 50-60, a baseline risk of PE is 10 to 20 events/100,000 woman-years.

Therefore, a twofold increased risk would be 40 events/100,000, a risk lower than that of normal pregnancy (60/100,000). This risk is not suggested to occur in women receiving transdermal estrogen according to clinical studies.

These statistics apply to women who have never had breast cancer which leads us to ponder how we should think about treating the high percentage of breast cancer survivors, many of whom experience debilitating symptoms of menopause secondary to chemotherapy. Should they be denied the benefits of ERT? Prior to the misleading dissemination of the WHI results, many investigators thought it was time to consider and study the effects of estrogen in breast cancer survivors.

“The categorical refusal [to prescribe HRT] is a double-edged sword…because it also denies these women all the indisputable health benefits HRT provides…This refusal is not, however, supported by the observational data available so far on this question, because HRT has not increased the risk for breast cancer recurrence.”

Conclusion

ERT:

• Decreases the risk of cardiovascular disease by 40-50%. Cardiovascular disease kills 1/5 women.
• Decreases the risk of hip fracture by 30-50%, more than medications currently being given for osteoporosis.
• Decreases the risk of Alzheimer’s by 45-70%
• Decreases the risk of and improves outcome of colon cancer.
• Increases the risk of venous and pulmonary thrombosis 40 events/100,000, less than a normal pregnancy.
• Increases life span by an additional 3-4 years.
• No studies have shown ERT increases risk of breast cancer

Part II, next week, will go over studies using HRT and ERT in breast cancer survivors.

Have an awesome day!  Dr D