Review: postmenopausal hormone replacement therapy is associated with a decreased risk of colorectal cancer
QUESTION: Is postmenopausal hormone replacement therapy associated with a decreased risk of colorectal cancer in women?
English language studies were identified by searching Medline (1966 to September 1998) using the subject headings for colorectal, colon, and rectal neoplasms or the textwords “colorectal, colon, and rectal cancer” and the subject headings “estrogen, estrogen replacement therapy” or the textwords “hormone replacement therapy, postmenopausal hormones, or non contraceptive hormones”. Bibliographies were also reviewed.
Studies were selected if they provided estimates of the risk of colon or rectal cancer in relation to postmenopausal hormone use.
Data were extracted on study design, cases of colon cancer, categories of hormone use (ever use, current use, and duration of use), odds ratios, relative risks (RRs), and 95% confidence intervals (CIs).
18 studies (9 prospective, 8 case control, and 1 clinical trial) …