Influence of different HRT regimens on mammographic density

The epidemiologic factors associated with breast density: A review

In recent years, some studies have evaluated the epidemiologic factors associated with breast density. However, the variant and inconsistent results exist. In addition, breast density has been proved to be a significant risk factor associated with breast cancer. Our review summarized the published studies and emphasized the crucial factors including epidemiological factors associated with breast density. In addition, we also discussed the potential reasons for the discrepant results with risk factors. To decrease the incidence and mortality rates for breast cancer, in clinical practice, breast density should be included for clinical risk models in addition to epidemiological factors, and physicians should get more concentrate on those women with risk factors and provide risk-based breast cancer screening regimens.

Heparanase Promotes Syndecan-1 Expression to Mediate Fibrillar Collagen and Mammographic Density in Human Breast Tissue Cultured ex vivo

Mammographic density (MD) is a strong and independent factor for breast cancer (BC) risk and is increasingly associated with BC progression. We have previously shown in mice that high MD, which is characterized by the preponderance of a fibrous stroma, facilitates BC xenograft growth and metastasis. This stroma is rich in extracellular matrix (ECM) factors, including heparan sulfate proteoglycans (HSPGs), such as the BC-associated syndecan-1 (SDC1). These proteoglycans tether growth factors, which are released by heparanase (HPSE). MD is positively associated with estrogen exposure and, in cell models, estrogen has been implicated in the upregulation of HPSE, the activity of which promotes SDC expression. Herein we describe a novel measurement approach (single-sided NMR) using a patient-derived explant (PDE) model of normal human (female) mammary tissue cultured ex vivo to investigate the role(s) of HPSE and SDC1 on MD. Relative HSPG gene and protein analyses determined in patient-paired high vs. low MD tissues identified SDC1 and SDC4 as potential mediators of MD. Using the PDE model we demonstrate that HPSE promotes SDC1 rather than SDC4 expression and cleavage, leading to increased MD. In this model system, synstatin (SSTN), an SDC1 inhibitory peptide designed to decouple SDC1-ITGαvβ3 parallel collagen alignment, reduced the abundance of fibrillar collagen as assessed by picrosirius red viewed under polarized light, and reduced MD. Our results reveal a potential role for HPSE in maintaining MD via its direct regulation of SDC1, which in turn physically tethers collagen into aligned fibers characteristic of MD. We propose that inhibitors of HPSE and/or SDC1 may afford an opportunity to reduce MD in high BC risk individuals and reduce MD-associated BC progression in conjunction with established BC therapies.

Factors Associated with Mammographic Density in Postmenopausal Women

Objectives

Breast density increases the risk of breast cancer, but also in the interpretation of mammography is also important. This study examine the risk factors affecting breast density in postmenopausal women.

Methods

Between January 2013 and January 2014, 215 patients admitted to The Clinics of Gynecology and Obstetrics with complaints of menopause were taken. According to the results of mammography, Group I (non-dense, n = 175) and Group II (dense, n = 40) were created. The informations of the caseswere analyzed retrospectively.

Results

In Group I, body mass index (BMI), number of pregnancies, parity were significantly higher than group II (P < 0.05). In group II, the withdrawal period of menstruation and progesterone levels were significantly higher (P < 0.05). In logistic regression analysis, BMI for dense breasts and number of pregnancies were found to be an independent risk factor (P < 0.05).

Conclusion

Increased BMI, pregnancy and parity, result of reduction in density , but longer duration of menopause and increased progesterone cause an increase in density. BMI and the number of pregnancy was found to be independent risk factors for reducing breast density.

Mammographic breast density in women with premature ovarian failure: a prospective analysis

OBJECTIVE

This study aims to compare breast density between two mammograms in women with premature ovarian failure (POF).

METHODS

A cohort study evaluated 56 women with POF. Two mammograms performed at least 2 years apart were analyzed. Mammogram films were digitalized, and images were assessed using a computer-assisted method; the percentage of breast image that is radiologically dense is referred to as the percentage of mammographic density (PMD). Age at menarche, age at onset of POF, length of POF, length of estrogen-progestin therapy (EPT), body mass index (BMI), pregnancy, and age at the time of each mammogram were evaluated.

RESULTS

The mean (SD) age at POF diagnosis was 32.35 (5.95) years. In the first mammogram, the mean (SD) age, BMI, and length of POF were 37.58 (3.72) years, 26.79 (4.86) kg/m, and 5.25 (4.61) years, respectively. EPT had been used for a mean (SD) of 2.71 (3.12) years. In the second mammogram, the mean (SD) age, BMI, and length of POF were 43.23 (4.98) years, 27.6 (5.39) kg/m, and 10.5 (5.11) years, respectively. EPT had been used for a mean (SD) of 7.25 (4.6) years. The mean (SD) interval between mammograms was 5.25 (3) years, and the mean (SD) PMD decreased from 27.78% (21.04%) to 17.53% (15.71%) (P = 0.007). Comparing PMD between women taking EPT and those not taking EPT, we observed no significant differences. In both instances, multiparous women had lower PMD than nulliparous women (P < 0.05). BMI, length of POF, and pregnancy were negatively correlated with PMD.

CONCLUSIONS

Breast density in young women with POF decreases across a period of 5 years, regardless of EPT use. Further studies may elucidate how this result will correlate with decision-making in clinical therapeutics and breast cancer risk in POF.

Endogenous sex hormones and breast density in young women

BACKGROUND

Breast density is a strong risk factor for breast cancer and reflects epithelial and stromal content. Breast tissue is particularly sensitive to hormonal stimuli before it fully differentiates following the first full-term pregnancy. Few studies have examined associations between sex hormones and breast density among young women.

METHODS

We conducted a cross-sectional study among 180 women ages 25 to 29 years old who participated in the Dietary Intervention Study in Children 2006 Follow-up Study. Eighty-five percent of participants attended a clinic visit during their luteal phase of menstrual cycle. Magnetic resonance imaging measured the percentage of dense breast volume (%DBV), absolute dense breast volume (ADBV), and absolute nondense breast volume (ANDBV). Multiple-linear mixed-effect regression models were used to evaluate the association of sex hormones and sex hormone-binding globulin (SHBG) with %DBV, ADBV, and ANDBV.

RESULTS

Testosterone was significantly positively associated with %DBV and ADBV. The multivariable geometric mean of %DBV and ADBV across testosterone quartiles increased from 16.5% to 20.3% and from 68.6 to 82.3 cm(3), respectively (Ptrend ≤ 0.03). There was no association of %DBV or ADBV with estrogens, progesterone, non-SHBG-bound testosterone, or SHBG (Ptrend ≥ 0.27). Neither sex hormones nor SHBG was associated with ANDBV except progesterone; however, the progesterone result was nonsignificant in analysis restricted to women in the luteal phase.

CONCLUSIONS

These findings suggest a modest positive association between testosterone and breast density in young women.

IMPACT

Hormonal influences at critical periods may contribute to morphologic differences in the breast associated with breast cancer risk later in life.

Breast density in women with premature ovarian failure or postmenopausal women using hormone therapy: analytical cross-sectional study

CONTEXT AND OBJECTIVE

Studies on postmenopausal women have reported increased risk of breast cancer relating to the type and duration of hormone therapy (HT) used. Women with premature ovarian failure (POF) represent a challenge, since they require prolonged HT. Little is known about the impact of prolonged HT use on these women's breasts. This study aimed to evaluate the effects of one type of HT on the breast density of women with POF, compared with postmenopausal women.

DESIGN AND SETTING

Cross-sectional study at the Department of Obstetrics and Gynecology, Universidade Estadual de Campinas (Unicamp).

METHODS

31 women with POF and 31 postmenopausal women, all using HT consisting of conjugated equine estrogen combined with medroxyprogesterone acetate, and matched according to HT duration, were studied. Mammography was performed on all subjects and was analyzed by means of digitization or Wolfe's classification, stratified into two categories: non-dense (N1 and P1 patterns) and dense (P2 and Dy).

RESULTS

No significant difference in breast density was found between the two groups through digitization or Wolfe's classification. From digitization, the mean breast density was 24.1% ± 14.6 and 18.1% ± 17.2 in the POF and postmenopausal groups, respectively (P = 0.15). Wolfe's classification identified dense breasts in 51.6% and 29.0%, respectively (P = 0.171).

CONCLUSION

There was no difference in breast density between the women with POF and postmenopausal women, who had used HT for the same length of time. These results may help towards compliance with HT use among women with POF.

Rationale for low-dose systemic hormone replacement therapy and review of estradiol 0.5 mg/NETA 0.1 mg

The menopausal transition is associated with several symptoms, for which both non-pharmacological and pharmacological measures are available to provide relief. However, present knowledge indicates that the former is not highly effective, and that the latter, in terms of systemic oestrogen and progestogen-based hormone replacement therapy (HRT), although being effective (e.g. on vasomotor symptoms, bleeding control, bone mineral density, vaginal atrophy and quality of life), can be associated with some caveats. Amongst these are an increased risk for coronary heart disease, breast cancer, venous thromboembolism and stroke. In recent years, literature has indicated a dose dependency for HRT on some of the caveats, hence authorities (Food and Drug Administration, and the European Medicines Agency) and menopause societies (International Menopause Society and North American Menopause Society) now recommend that women deemed in need of HRT should receive the lowest possible dose without compromising the effect of symptom relief. Estradiol 0.5 mg/norethisterone acetate (NETA) 0.1 mg, despite being a lower dose than conventional hormones, is a compound, among a few other low-dose options, that can be used in such therapy. As a first-line oral option, it has demonstrated its effectiveness (which seems comparable to other compounds), with high tolerability and, apparently, no safety concerns, in a 6-month study. Further long-term clinical trials and observational studies are mandatory in order to capture any potential harm as well as to elucidate this compound's full potential. Following a thorough literature search using PubMed and MEDLINE from the earliest publication dates through to January 2008, including results from various types of clinical trials and statements on HRT, we review the rationale for these recommendations. We also review the effects and safety of a novel 'ultra-low-dose' oral continuous combined HRT tablet, estradiol 0.5 mg/NETA 0.1 mg.

An isopropanolic extract of black cohosh does not increase mammographic breast density or breast cell proliferation in postmenopausal women

OBJECTIVE

The aim of this study was to determine the effects of the isopropanolic extract of black cohosh (Remifemin) on mammographic breast density and breast epithelial proliferation in healthy, naturally postmenopausal women with climacteric symptoms.

DESIGN

This was a prospective, open, uncontrolled drug safety study in which baseline status was compared with status after 6 months of treatment by blinded observers. A total of 74 women were treated with 40 mg black cohosh daily, and 65 women completed the study. Mammograms were performed, and breast cells were collected by percutaneous fine needle aspiration biopsies at baseline and after 6 months. Mammographic density was quantified according to the Wolfe classification or a percentage scale. Breast cell proliferation was assessed using the Ki-67/MIB-1 monoclonal antibody. Safety was monitored by adverse event reporting, laboratory assessments, and measurement of the endometrium by vaginal ultrasound.

RESULTS

None of the women showed any increase in mammographic breast density. Furthermore, there was no increase in breast cell proliferation. The mean change +/- SD in proportion of Ki-67-positive cells was -0.5% +/- 2.4% (median, 0.0; 95% CI = -1.32 to 0.34) for paired samples. The mean change in endometrial thickness +/- SD was 0.0 +/- 0.9 mm (median, 0.0). A modest number of adverse events were possibly related to treatment, but none of these were serious. Laboratory findings and vital signs were normal.

CONCLUSIONS

The findings suggest that the isopropanolic extract of black cohosh does not cause adverse effects on breast tissue. Furthermore, our data do not indicate to any endometrial or general safety concerns during 6 months of treatment.

Effects of hormone replacement therapy regimens on mammographic breast density: The role of progestins

AIM

To evaluate the effects of different regimens of hormone replacement therapy (HRT) on mammographic breast density.

METHODS

Mammograms of 113 healthy postmenopausal women who were on different HRT regimens were evaluated retrospectively. All women had a baseline mammography and at least one mammogram after at least 12 months of HRT. Four parenchymal patterns were considered mammographically. Quantification of density changes that occurred on follow-up mammograms was done qualitatively and with reference to densities on baseline mammograms.

RESULTS

Sixty women were treated with a continuous estrogen-progestin combination; 16 with a cyclic estrogen-progestin combination and 37 were with estrogen only. Twenty-six women had increased mammographic density after HRT. Mammographic density increase was detected in 23 women (38.3%) of the continuous estrogen-progestin combination group, two women (12.5%) of the cyclic estrogen-progestin combination group and one woman (2.7%) of the estrogen-only group. Mammographic density increase was more common among women in the continuous estrogen-progestin combination group than the other groups and this difference was found to be statistically significant (P < 0.001). Breast density increase was observed in 18 of 30 women (60%) with higher doses of progestin compared to 5 of 30 women (16.7%) with lower dose (P < 0.05).

CONCLUSIONS

Postmenopausal HRT may increase mammographic breast density. Breast density appears to be mostly affected by higher doses and continuous administration of progestin.

The effect of low dose hormone therapy on mammographic breast density

OBJECTIVES

To evaluate the effect of two standard and one low dose continuous hormone therapy regimens on mammography.

METHODS

One hundred and thirty-two non-hysterectomized postmenopausal women were randomly allocated either to conjugated equine estrogens 0.625 mg plus medroxyprogesterone acetate 5 mg (CEE/MPA, n=38), 17beta-estradiol 2 mg plus norethisterone acetate 1 mg (E2/NETA, n=44) or 17beta-estradiol 1 mg plus norethisterone acetate 0.5 mg (low E2/NETA, n=50). Treatment was continuous and the study period lasted 12 months. Main outcome measures were the changes according to Wolfe classification between baseline and 12-month mammograms.

RESULTS

Five (13.2%) women in the CEE/MPA group showed an increase in breast density. Fourteen (31.8%) women on E2/NETA and 6 (12.2%) on low E2/NETA treatment revealed an increase in breast density. No woman exhibited an involution of fibroglandular tissue.

CONCLUSIONS

Different hormone therapy regimens have a variable impact on breast density probably depending on the steroid used. Low dose hormone therapy associates with significantly lesser increase in breast density.