The clinical scenario is as follows: A 62-year-old woman comes to see me for a new diagnosis of grade 1 endometrial cancer. She has a normal body mass index of 24 kg/m2, a history of four prior full-term pregnancies, no family history of malignancy, and no medical comorbidities. She is otherwise a specimen of good health, and has no clear identifiable risk factors for this malignancy. She then reports that she transitioned through menopause at age 52 years and developed severe hot flashes with sleep and mood disturbance. She did not wish to take conventional hormone replacement therapy (HT) because she had heard it causes cancer. She subsequently researched the Internet and found a provider who has been prescribing compounded bioidentical hormone therapy (CBHT) for her for the past 10 years. She submits saliva for testing of her estrogen levels, and the provider uses this data to compound the appropriate doses of “natural” estrogens and testosterone for her which she applies via vaginal or transdermal creams. She has been prescribed a progesterone suppository, but she doesn’t always take that because she doesn’t notice that it has any effect on how she feels.
My answer is, of course, I don’t know. Cancer is a complex disease with a complex array of causative and promoting factors. However, we do know that taking estrogen unopposed with adequate progesterone can cause the development of uterine cancer and its precursor state.1 If those bioidentical estrogens were effective at controlling her menopausal symptoms, they likely were effective at stimulating her endometrium at the same time.
What are compounded bioidentical hormones?
The term “bioidentical” refers to having the same molecular structure as that which is found in the human body. Examples of bioidentical estrogens include 17-beta-estradiol, estrone, and estriol – which are produced from yams and soy. Micronized progesterone is an example of a bioidentical progesterone. Many of these drugs are approved by the Food and Drug Administration, and prescribed and dispensed by conventional pharmacies.
An alternative, and increasingly popular, version of bioidentical hormones are CBHs. It should be recognized that this is a marketing, and not a scientific, term. These products utilize hormones, in some cases FDA-approved bioidentical hormones, that are broken down and blended by specialized pharmacies and reconstituted (compounded) into different, and sometimes “customized,” dosing and delivery methods (such as capsules, patches, gels, creams, lozenges, suppositories). Frequently used compounded products utilize multiple formulations of estrogens in doublets and triplets as well as progesterone, testosterone, and dehydroepiandrosterone.
How do they differ from synthetic hormones?
Distributors of CBHs state that they differ from conventional HT (synthetic and bioidentical) because of the customization process from which they promise greater efficacy and a sense of personalized medicine. The distributors frequently utilize assays from saliva, blood, vaginal secretions, and urine to measure a woman’s hormone levels, and titrate her compounded formulation based on those results. It should be noted that there is no data to support that titration of hormones to blood, salivary, or urine levels is efficacious or ensures greater safety than titration based on symptom management.