|
|
|
|
|
|
|
|
Blogger's Notes: WHI/post-WHI studies indicated that HRT had a protective effect on colorectal cancer (info needs to be updated) eg. estrogen
abstract
Background
The
development of colorectal cancer is influenced by hormonal factors.
Oophorectomy alters endogenous levels of sex hormones, but the effect on
colorectal cancer risk is unclear. The aim of this cohort study was to
examine colorectal cancer risk after oophorectomy for benign
indications.
Methods
Women
who had undergone oophorectomy between 1965 and 2011 were identified
from the Swedish Patient Registry. Standard incidence ratios (SIRs) and
95 per cent confidence intervals for colorectal cancer risk were
calculated compared with those in the general population. Stratification
was carried out for unilateral and bilateral oophorectomy, and
hysterectomy without specification of whether the ovaries were removed
or not. Associations between the three oophorectomy options and
colorectal cancer risk in different locations were assessed by means of
hazard ratios (HRs) and 95 per cent confidence intervals calculated by
Cox proportional hazards regression modelling.
Results
Of
195 973 women who had undergone oophorectomy, 3150 (1·6 per cent) were
diagnosed with colorectal cancer at a later date (median follow-up 18
years). Colorectal cancer risk was increased after oophorectomy compared
with that in the general population (SIR 1·30, 95 per cent c.i. 1·26 to
1·35). The risk was lower for younger age at oophorectomy (15–39 years:
SIR 1·10, 0·97 to 1·23; 40–49 years: SIR 1·26, 1·19 to 1·33; P for trend < 0·001). The risk was highest 1–4 years after oophorectomy (SIR 1·66, 1·51 to 1·81; P
< 0·001). In the multivariable analysis, women who underwent
bilateral oophorectomy had a higher risk of rectal cancer than those who
had only unilateral oophorectomy (HR 2·28, 95 per cent c.i. 1·33 to
3·91).
Conclusion
Colorectal cancer risk is increased after oophorectomy for benign indications.
0 comments :
Post a Comment
Your comments?
Note: Only a member of this blog may post a comment.