Progesterone and progestogens cause breast cancer Re: Use of hormone replacement therapy and risk of breast cancer: nested case-control studies using the QResearch and CPRD databases
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Use of hormone replacement therapy and risk of breast cancer: nested case-control studies using the QResearch and CPRD databases
Progesterone and progestogens cause breast cancer Re: Use of hormone replacement therapy and risk of breast cancer: nested case-control studies using the QResearch and CPRD databases
Dear Editor
Dr Peter Lewis responds that progestogens increase the risk of breast cancer but not "natural" progesterone. He ignores the fact that both act by stimulating progesterone receptors and that oral progesterone is micronized to aid alimentary absorption and double its progestogenic potency. Also he ignores the fact that The Collaborative Group on Hormonal Factors in Breast Cancer reviewed "all the available relevant randomised evidence” and found risks did not generally differ between different progestagenic constituents. In fact, micronized progesterone and oestrogen significantly doubled the risk of breast cancer (RR 2.05 (1.38-3.56). [1]
It should never be forgotten that in 1896 Colonel Sir George Thomas Beatson discovered that oophorectomy, which stopped the endogenous secretion of both oestrogens and progesterone from functioning ovaries, remitted metastatic breast cancers. Beatson is considered the father of anti-hormonal treatment of breast cancer as oophorectomy became the standard treatment for advanced breast cancer.
Women are still being overwhelmed by HRT promotions, although there is irrefutable evidence that falls in HRT use lowers both breast cancer incidence and mortality. [1,2]
1 Collaborative Group on Hormonal Factors in Breast Cancer (2019) Type and timing of menopausal therapy and breast cancer risk individual participant meta-analysis of the worldwide epidemiological evidence. Lancet 394: 1159-1168.
2 Beral V, Peto R, Pirie K, Reeves G. Menopausal hormone therapy and 20-year breast cancer mortality. Lancet Published Online August 29, 2019 http://dx.doi.org/10.1016/ S0140-6736(19)32033-12
Rapid Response:
Progesterone and progestogens cause breast cancer Re: Use of hormone replacement therapy and risk of breast cancer: nested case-control studies using the QResearch and CPRD databases
Dear Editor
Dr Peter Lewis responds that progestogens increase the risk of breast cancer but not "natural" progesterone. He ignores the fact that both act by stimulating progesterone receptors and that oral progesterone is micronized to aid alimentary absorption and double its progestogenic potency. Also he ignores the fact that The Collaborative Group on Hormonal Factors in Breast Cancer reviewed "all the available relevant randomised evidence” and found risks did not generally differ between different progestagenic constituents. In fact, micronized progesterone and oestrogen significantly doubled the risk of breast cancer (RR 2.05 (1.38-3.56). [1]
It should never be forgotten that in 1896 Colonel Sir George Thomas Beatson discovered that oophorectomy, which stopped the endogenous secretion of both oestrogens and progesterone from functioning ovaries, remitted metastatic breast cancers. Beatson is considered the father of anti-hormonal treatment of breast cancer as oophorectomy became the standard treatment for advanced breast cancer.
Women are still being overwhelmed by HRT promotions, although there is irrefutable evidence that falls in HRT use lowers both breast cancer incidence and mortality. [1,2]
1 Collaborative Group on Hormonal Factors in Breast Cancer (2019) Type and timing of menopausal therapy and breast cancer risk individual participant meta-analysis of the worldwide epidemiological evidence. Lancet 394: 1159-1168.
2 Beral V, Peto R, Pirie K, Reeves G. Menopausal hormone therapy and 20-year breast cancer mortality. Lancet Published Online August 29, 2019 http://dx.doi.org/10.1016/ S0140-6736(19)32033-12
Competing interests: No competing interests