Mammographic Breast Density in Infertile and Parous Women

Meggiorini Maria Letizia; Vestri Anna Rita; De Stefano Maria Grazia; Cipolla Valentina; Bellati Filippo; Maffucci Diana; Nusiner Maria Paola; Aragona Cesare; De Felice Carlo

Disclosures

BMC Womens Health. 2016;16(8) 

In This Article

Background

Infertility is defined as the failure to conceive after one year of regular unprotected intercourse, and prevalence is approximately 10 %-15 % in Western countries.[1] The demand for infertility services is steadily increasing, and so is the average age of women undergoing in vitro fertilization (IVF).[2,3] Infertility treatments implying medication and interventional procedures may modify the hormonal environment and be cofactors in cellular changes leading to cancer development.[4,5] However, few studies are reported on breast cancer risk in infertile women who have undergone IVF treatment.[6–8]

The association between breast cancer and infertility has not been consistently studied, but it may be explained by hormonal disorders linked to infertility, a different reproductive risk factor profile in infertile women, or by a combination of these two factors.

Two decades ago, Sellers et al. reported a significantly higher risk of developing breast cancer in nulliparous married women who tried and failed to become pregnant.[9] Weiss et al.[10] found that among women with a first full-term delivery at the age of 35 or older, fertility problems were associated with a two-fold increased risk of breast cancer. In contrast, Venn et al.[5] and Klip et al.[8] summarized the association between infertility and breast cancer and concluded that infertile women did not appear to be at higher risk for breast cancer. However, the possible influence of infertility itself on the risk of breast cancer occurrence should be taken into consideration.[11]

The Italian National Federation for Breast Cancer (FONCAM) guidelines 2005 recommend mammography starting at 35 years in women who undergo hormone therapy.[12]

At the Breast Unit of our institution (Policlinico Umberto I, Rome), all women undergoing fertility treatment are submitted to breast examination, and mammography is performed according to the FONCAM recommendations for women aged ≥35.

Mammographic breast density reflects the relative proportion of glandular and stromal tissue to fatty tissue in the breast. High breast density has been strongly associated with increased risk of breast cancer,[13–15] and this parameter could thus be a useful marker for breast cancer risk and be considered one of the strongest risk factors for breast cancer.[15] Breast density is often associated with reproductive and menstrual factors including serum estrogen and progesterone concentrations.[16] Furthermore, breast density is inversely correlated with the accuracy of mammography and therefore a measurement of density conveys information on the difficulty of detecting cancer in a mammogram.

In a previous study, we found that 68 % of women with primary infertility had dense breast tissue according to the BIRADS score compared with 37 % of premenopausal women in a general population.[17]

In the present study, two different systems, BIRADS and Boyd, were employed to evaluate mammographic breast density in two selected groups: a case group consisting of infertile women and a control group consisting of parous women. The results obtained in the two groups were subsequently compared.

processing....