[Is the clinical profile of women treated with tibolone similar to that of women receiving a classical estrogen-progestogen therapy? Data from a nationwide survey in France].

OBJECTIVES

To compare the pre-existing risk profiles for breast or endometrial cancer of menopaused women receiving tibolone or another hormone replacement therapy in France, with a view to examining the possibility of biases of selection of patients and of detection of these cancers in the Million Women Study.

PATIENTS AND

METHODS

Nationwide survey conducted in France among a representative sample of 153 gynaecologists. The particulars of the last two consulting menopaused women treated with tibolone (N = 306) and of the last two treated with a classical estrogen-progestogen therapy (N = 306) were collated then analysed.

RESULTS

Compared to those treated with a classical estrogen-progestogen therapy, more women receiving tibolone were aged 60 years or over (40 vs 31%; P < 0.01). More of them had risk factors for breast cancer (history of mastodynia or mastopathy, elevated mammographic breast density) (6 vs 50%; P < 0.01). More of them had a history of uterine investigation or exploration or of irregular bleeding (61 vs 53% of women with a history of irregular bleeding; P < 0.05). Overall, 84% of women treated with tibolone had at least one risk factor for breast or endometrial cancer vs 75% of those receiving a classical estrogen-progestogen therapy (P < 0.01).

DISCUSSION AND

CONCLUSION

Owing to its specific properties, tibolone is generally prescribed to women with a higher risk profile for breast or endometrial cancer than those receiving a classical estrogen-progestogen therapy, which may entail patient selection and cancer detection biases in non-randomised, open-label, observational studies.