A recently published paper has evaluated colorectal cancer risk associated with the duration and recency of specific menopausal hormone therapy formulations viz. unopposed estrogen versus estrogen combined with continuously or sequentially administered progestin among 56,733 postmenopausal women participating in the Breast Cancer Detection Demonstration Project (BCDDP) follow-up study [1]. There were 960 women who were identified to have developed colorectal cancer over a mean follow-up period of 15 years and mean age at commencement of follow-up of 55.7 years. Current use of estrogen (relative risk (RR), 0.75; 95% confidence interval (CI), 0.54–1.05) and duration of use of > 10 years (RR, 0.74; 95% CI, 0.56–0.96) were associated with the largest reduction of risk compared to non-users. Estrogen with sequentially administered progestin for < 15 days per cycle (RR, 0.64; 95% CI, 0.43–0.95) was more protective than continuous combined estrogen and progestin therapy.
Author(s)
-
Farook Al-Azzawi
Menopause Research Unit, University Hospitals of Leicester, Leicester, UK
Citations
-
Johnson JR, Lacey JV Jr, Lazovich D, et al. Menopausal hormone therapy and risk of colorectal cancer. Cancer Epidemiol Biomarkers Prev 2009;18:196-203. Published January 2009.
http://www.ncbi.nlm.nih.gov/pubmed/19124498 -
Anderson GL, Limacher M, Assaf AR, et al. Effects of conjugated equine estrogen in postmenopausal women with hysterectomy: the Womens Health Initiative randomized controlled trial. JAMA 2004;291:1701-12.
http://www.ncbi.nlm.nih.gov/pubmed/15082697 -
Chlebowski RT, Wactawski-Wende J, Ritenbaugh C, et al. Estrogen plus progestin and colorectal cancer in postmenopausal women. N Engl J Med 2004;350:991-1004.
http://www.ncbi.nlm.nih.gov/pubmed/14999111 -
English MA, Kane KF, Cruickshank N, Langman MJ, Stewart PM, Hewison M. Loss of estrogen inactivation in colonic cancer. J Clin Endocrinol Metab 1999;84:2080-5.
http://www.ncbi.nlm.nih.gov/pubmed/10372714 -
English MA, Hughes SV, Kane KF, Langman MJ, Stewart PM, Hewison M. Oestrogen inactivation in the colon: analysis of the expression and regulation of 17beta-hydroxysteroid dehydrogenase isozymes in normal colon and colonic cancer. Br J Cancer 2000;83:550-8.
http://www.ncbi.nlm.nih.gov/pubmed/10945506 -
Slattery ML, Samowitz WS, Holden JA. Estrogen and progesterone receptors in colon tumors. Am J Clin Pathol 2000;113:364-8.
http://www.ncbi.nlm.nih.gov/pubmed/10705816 -
Foley EF, Jazaeri AA, Shupnik MA, Jazaeri O, Rice LW. Selective loss of estrogen receptor beta in malignant human colon. Cancer Res 2000;60:245-8.
http://www.ncbi.nlm.nih.gov/pubmed/10667568 -
Cedar H. DNA methylation and gene activity. Cell 1988;53:3-4.
http://www.ncbi.nlm.nih.gov/pubmed/3280142 -
Issa JP, Ottaviano YL, Celano P, Hamilton SR, Davidson NE, Baylin SB. Methylation of the oestrogen receptor CpG island links ageing and neoplasia in human colon. Nat Genet 1994;7:536-40.
http://www.ncbi.nlm.nih.gov/pubmed/7951326 -
Horvath G, Leser G, Karlsson L, Delle U. Estradiol regulates tumor growth by influencing p53 and bcl-2 expression in human endometrial adenocarcinomas grown in nude mice. In Vivo 1996;10:411-16.
http://www.ncbi.nlm.nih.gov/pubmed/8839787 -
Jiang SY, Jordan VC. Growth regulation of estrogen receptor-negative breast cancer cells transfected with complementary DNAs for estrogen receptor. J Natl Cancer Inst 1992;84:580-91.
http://www.ncbi.nlm.nih.gov/pubmed/1556769