Hysterectomy and risk of breast, colorectal, thyroid and kidney cancer - an Australian data linkage study
Menée en Australie à partir de données portant sur 839 332 femmes, cette étude analyse l'association entre une hystérectomie pour des indications bénignes et le risque de cancer mammaire, colorectal, rénal et thyroïdien, selon l'âge au moment de la chirurgie et en fonction de la conservation des ovaires ou non
Background: This study aimed to investigate the associations between hysterectomy for benign indications and risk of breast, colorectal, kidney and thyroid cancer; and to explore whether these associations are modified by removal of ovaries at the time of surgery or age at surgery. Methods: We conducted a retrospective cohort study of the female population of Western Australia (n=839,332) linking data from electoral, hospital, births, deaths and cancer records. We used Cox regression to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the associations between hysterectomy and diagnosis of breast, colorectal, kidney and thyroid cancers. Results: Compared to no surgery, hysterectomy without oophorectomy (hysterectomy) and hysterectomy-BSO were associated with higher risk of kidney cancer (HR, 1.32; 95% CI, 1.11-1.56 and HR, 1.29; 95% CI, 0.96-1.73 respectively). Hysterectomy, but not hysterectomy-BSO, was related to higher risk of thyroid cancer (HR, 1.38; 95% CI, 1.19-1.60). In contrast, hysterectomy (HR, 0.94; 95% CI, 0.90-0.98) and hysterectomy-BSO (HR, 0.92; 95% CI, 0.85-1.00) were associated with lower risk of breast cancer. We found no association between hysterectomy status and colorectal cancer. Conclusions: The associations between hysterectomy and cancer varied by cancer type with increased risks for thyroid and kidney cancer, decreased risk for breast cancer and no association for colorectal cancer. Impact: As breast, colorectal and gynaecological cancers comprise a sizeable proportion of all cancers in women, our results suggest that hysterectomy is unlikely to increase overall cancer risk; however, further research to understand the higher risk of thyroid and kidney cancer is warranted.