Related Experiment Videos
Is a dense mammographic parenchymal pattern a contraindication to hormonal replacement therapy?
T M Salminen1, I E Saarenmaa, M M Heikkilä
1Tampere School of Public Health, University of Tampere, Finland. cstisa@uta.fi
Acta Oncologica (Stockholm, Sweden)
|February 24, 2001
Summary
Hormonal replacement therapy (HRT) did not affect breast cancer risk alone. However, women with dense mammographic patterns (DY) using HRT had a significantly higher risk of breast cancer.
Area of Science:
- Oncology
- Radiology
- Endocrinology
Background:
- Mammographic parenchymal patterns (MPP) are indicators of breast density and may influence breast cancer risk.
- Hormonal replacement therapy (HRT) use is widespread among postmenopausal women and its effect on breast cancer risk is debated.
- Potential interactions between HRP and genetic or environmental factors, such as MPP, require further investigation.
Purpose of the Study:
- To investigate whether mammographic parenchymal patterns modify the association between hormonal replacement therapy (HRT) and breast cancer risk.
- To identify specific mammographic patterns that may indicate increased breast cancer risk in HRT users.
Main Methods:
- A cohort study of 4163 Finnish women aged 40-47 years at entry, followed from 1982 to 1993.
- Mammographic parenchymal patterns (Wolfe's classification) were assessed at screening rounds between 1982 and 1990.
- Hormonal replacement therapy (HRT) use was recorded from 1984, and breast cancer diagnoses were ascertained until 1993.
- Poisson regression models were employed to analyze the data, adjusting for age.
Main Results:
- Hormonal replacement therapy (HRT) use alone was not significantly associated with breast cancer risk (RR = 0.7, 95% CI 0.4-1.4).
- Specific mammographic parenchymal patterns were significantly associated with breast cancer risk: P2 pattern (RR = 2.5, 95% CI 1.3-4.8) and DY pattern (RR = 4.9, 95% CI 1.6-15.1) compared to N1 pattern.
- Women with the DY mammographic pattern who used HRT exhibited a substantially increased risk of breast cancer (RR = 11.6, 95% CI 2.5-53.6) compared to women with the N1 pattern not using HRT, suggesting a synergistic effect.
Conclusions:
- Mammographic parenchymal patterns, particularly the DY pattern, are significant risk factors for breast cancer.
- The combination of HRT use and the DY mammographic pattern confers a substantially elevated risk of breast cancer.
- These findings highlight the importance of considering mammographic density in risk assessment for breast cancer in women using HRT.