Is there a reduced risk of breast cancer among women with hip fractures?

French recommendations on strategies for preventing and treating osteoporosis induced by adjuvant breast cancer therapies

Standard adjuvant therapies for breast cancer such as chemotherapy or aromatase inhibitor and LH-RH agonist hormone therapy are associated with significant survival gains but also induce bone loss by aggravating the estrogen deprivation. The bone loss may be substantial, notably during early treatment, and occurs regardless of the baseline bone mineral density values. The objective of developing these recommendations was to achieve a practical consensus among various scientific societies, based on literature review, about osteoporosis prevention and treatment in these patients. The following scientific societies contributed to the work: Société Française de Rhumatologie (SFR), Groupe de Recherche et d'Information sur les Ostéoporoses (GRIO), Groupe Européen d'Etudes des Métastases Osseuses (GEMO), Association Francophone pour les Soins Oncologiques de Support (AFSOS), Société Française de Sénologie et de Pathologie Mammaire (SFSPM), Société Française de Radiothérapie Oncologique (SFRO). Drug prescription and reimbursement modalities in France were taken into account. These recommendations apply to postmenopausal women taking systemic chemotherapy and/or aromatase inhibitor therapy, non-postmenopausal women taking LH-RH agonist therapy, and non-postmenopausal women with persistent amenorrhea 1 year after chemotherapy completion. All women in these three categories should undergo an evaluation of bone health and receive interventions to combat risk factors for bone loss. Patients with a history of severe osteoporotic fracture and/or a T-score value <-2.5 should receive osteoporosis drug therapy. The FRAX® score should be used to guide treatment decisions in patients whose T-score is between -1 and -2.5. General osteoporosis prevention measures should be applied in patients without criteria for osteoporosis drug therapy, who should undergo bone mineral density measurements 18-24 months later if the baseline T-score is<-1 and 3-5 years later if the baseline T-score is>-1. The anti-tumor effect of bisphosphonates and denosumab was not considered when establishing these recommendations.

The relationship between breast density and bone mineral density after menopause

[Purpose] The purpose of this study was to analyze the relationship between breast density and bone mineral density after menopause. [Subjects and Methods] The subjects were 130 patients who participated in a bone densitometry test and had a mammogram taken between January 1st, 2013 to October 1st, 2014. The mammograms were scored breast imaging-reporting and data system. Grade 1 indicates almost only fat, Grade 2 indicates fibroglandular densities, Grade 3 indicates heterogeneously dense tissue, and Grade 4 indicates an extreme density. Correlation analysis was carried out to investigate the relationship between breast density grades and bone mineral densities by age and body mass index. [Results] Breast density had a close relationship with age (−0.59), Body mass index (−0.39), and T-score (0.29). The results indicate that as age and body mass index increase, the grade of the breast density decreases, and as the T-score increases, the grade increases. [Conclusion] A precise evaluation of the of breast cancer risk associated with breast density should be conducted as a large scale prospective study for women in Korea.

Fracture risk in women with breast cancer: a population-based study

A positive association has been reported between greater bone density and higher breast cancer risk, suggesting that these women could be at reduced risk of fracture. To estimate fracture risk among unselected community women with breast cancer and to systematically assess associations with various risk factors including breast cancer treatments, we conducted a population-based historical cohort study of 608 Olmsted County, MN, USA, women with invasive breast cancer first diagnosed in 1990 to 1999 (mean age 61.6 ± 14.8 years), who were followed for 5776 person-years. Altogether, 568 fractures were observed in 270 women (98 per 1000 person-years). Overall fracture risk was elevated 1.8-fold, but the absolute increase in risk was only 9%, and 56% of the women did not experience a fracture during follow-up. Excluding pathologic fractures (15%) and those found incidentally (24%), to allow for ascertainment bias, the standardized incidence ratio was 1.2 (95% confidence interval [CI] 0.99 to 1.3) for total fracture risk and 0.9 (95% CI 0.7 to 1.2) for osteoporotic fracture risk alone. Various breast cancer treatments were associated with an increased risk of fracture, but those associations were strongest for pathologic fractures, which were relatively more common among the women who were premenopausal when their breast cancer was diagnosed. Moreover, underlying clinical characteristics prompting different treatments may have been partially responsible for the associated fracture outcomes (indication bias). These data thus demonstrate that breast cancer patients in general are not at greatly increased risk of fracture but neither are they protected from fractures despite any determinants that breast cancer and high bone density may have in common.

Bone mass density, subsequent risk of colon cancer and survival in postmenopausal women

OBJECTIVES

To test the hypothesis that high bone mass density (BMD), a potential marker for cumulative exposure to endogenous estrogen, calcium and vitamin D intake, is associated with a lower risk of colon cancer, and that women with a lower BMD are likely to develop a more aggressive form of colon cancer, as defined by mortality.

STUDY DESIGN AND SETTING

BMD was measured in three different sites (Ward's triangle, trochanter, femoral neck) in 1,471 women 60 years of age. All incident cases of colon cancers were identified through record-linkage of cancer registry. The women were followed for a mean of 9.5 years.

RESULTS

Overall 31 cases of colon cancer were observed among 28.6 expected (standardized incidence ratio (SIR) = 1.09, 95% confidence interval: 0.79-1.25). The SIR decreased with increasing BMD showing a significantly decreasing risk of 20% for women who were at the higher BMD comparatively to women who were at the lower BMD in all the skeletal sites. The 10-year survival rates showed that survival was increasing with increased BMD, but not significantly.

CONCLUSION

The findings suggest that postmenopausal women with lower BMD have an increased risk of colon cancer. The biological mechanisms linking bone mass to colon cancer risk are not clear.

Risks of cancer among a cohort of 23,935 men and women with osteoporosis

Low hormone levels among persons with osteoporosis may decrease risk of some cancers. Other osteoporosis risk factors, such as smoking and alcohol consumption, however, may increase risk. As these deleterious factors are more often associated with osteoporosis diagnosed prior to age 70 years, cancer risk may be higher in these younger persons than in the general population. To examine this hypothesis, a cohort study of 23,935 persons with osteoporosis was conducted in Denmark. Patients hospitalized with osteoporosis between 1978 and 1993 were identified in the Danish Inpatient Register. Linkage to the Danish Cancer Registry identified all cancer outcomes through 2003. Standardized incidence ratios (SIR) and 95% confidence intervals (95%CI) were calculated to compare cancer incidence in the cohort with that in the general population. Persons diagnosed prior to age 70 years were at increased cancer risk (women: SIR = 1.11, 95%CI = 1.04-1.19; men: SIR = 1.31, 95%CI = 1.13-1.50) due, in part, to increased risks of cancers of the buccal cavity, esophagus, liver, pancreas and lung. Persons diagnosed at ages 70 and older were at decreased risk (women: SIR = 0.91, 95%CI = 0.87-0.96; men: SIR = 0.89, 0.77-1.01) due, in part, to decreased risks of breast, endometrial, colon, rectal and brain cancers in women and prostate cancer in men. These results suggest that risk factors associated with earlier onset osteoporosis may be associated with increased risk of cancer. Conversely, factors associated with later onset osteoporosis may be related to a decreased risk of cancer.

Clinical management of osteoporosis in women with a history of breast carcinoma

Osteoporosis is a skeletal disorder that is characterized by low bone mass and compromised bone strength. Fractures are the clinically important consequence of osteoporosis and result not only in disability but also in excess mortality. Women who have a history of breast carcinoma may represent a unique population for whom screening and treatment for osteoporosis should be modified. A review of the English literature was performed that included original, review, consensus, and statement articles that were identified through Medline or National Institutes of Health-related links. According to the literature, osteoporosis constitutes a major public health problem. Approximately 55% of the U.S. population > or = 50 years of age has low bone mass (osteopenia or osteoporosis). Annually, > 200,000 women in the U.S. are diagnosed with breast carcinoma. Due to the high prevalence rates of both low bone mass and breast carcinoma in women, these two diseases commonly coexist in the same individuals. Women with a history of breast carcinoma may be at increased risk of developing bone loss and fragility fractures as a consequence of antineoplastic therapies. The majority of women treated for early-stage breast carcinoma do not develop recurrences, as a result of recent advances in therapy. Ensuring the diagnosis, prevention, and treatment of long-term toxicities and comorbid conditions like osteoporosis in breast carcinoma survivors is a serious concern and is of increasing importance. In this article, the authors address the evaluation and treatment of osteoporosis in women who have a history of early-stage breast carcinoma.

Low risk of hip fracture among elderly breast cancer survivors

PURPOSE

Prior research has shown that women with either osteoporotic fracture or low bone density are at a decreased risk of breast cancer. Little prior work has evaluated whether women with breast cancer are at a decreased risk of osteoporotic fracture.

METHODS

We used data from the National Cancer Institute's Surveillance Epidemiology and End Results (SEER)-Medicare program to study the risk of hip fracture among elderly female Medicare beneficiaries with and without histories of breast cancer. Using the SEER file, we identified elderly women survivors of stage 0, I, or II breast cancer (N=5980) diagnosed between the ages of 55 and 64 years; using the Medicare 5% file, we identified elderly women without histories of cancer (N=23,165) from SEER regions. Using Medicare claims from 1993 through 1998, we followed women for hospitalization for hip fracture or death until December 31, 1998.

RESULTS

We found the rate ratio of hospitalization for hip fracture for breast cancer survivors relative to comparison patients was 0.63 (95% CI: 0.43-0.94) after adjusting for age, race, socioeconomic status, geographic location, cohort entry year, and medical comorbidity.

CONCLUSIONS

We conclude that survivors of early stage post-menopausal breast cancer are at significantly lower risk of hip fracture than women who do not have histories of breast cancer.

Favorable cardiac risk among elderly breast carcinoma survivors

BACKGROUND

There are two reasons why women who survive breast carcinoma may be at a lower risk of developing coronary heart disease (CHD) compared with women without a history of breast carcinoma. First, estrogens may be etiologic in the development of breast carcinoma and protective of CHD. Second, a common therapy for breast carcinoma (tamoxifen) may be associated with cardiac protection.

METHODS

In this population-level cohort study, the authors analyzed data from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER)-Medicare program to study the cardiac risk of elderly female Medicare beneficiaries with and without a history of breast carcinoma. Using the SEER file, the authors identified elderly women survivors of Stage 0, I, or II breast carcinoma (n = 5980) diagnosed between the ages of 55 and 64. Using the Medicare 5% noncancer file, the authors also identified elderly women without a history of cancer (n = 23,165). They followed women from age 67 for up to 5 years for hospitalization for acute myocardial infarction (AMI) through a review of Medicare claims. The authors controlled the analyses for race, socioeconomic status, geographic location, cohort entry year, and medical comorbidity.

RESULTS

The hazard of hospitalization for AMI for breast carcinoma survivors relative to comparison patients was 0.66 (95% confidence interval, 0.49-0.88). This apparent cardioprotective effect of breast carcinoma survivorship was stronger in breast carcinoma survivors with documented cardiac risk factors.

CONCLUSIONS

Survivors of early-stage postmenopausal breast carcinoma are at a significantly lower risk of hospitalization for AMI than women who do not have a history of breast carcinoma. That survivors' risk varies with previous cardiac risk factors may be consistent with effects of selective estrogen receptor modulators. This phenomenon should be evaluated further with individual-level data containing information on patient cardiac risk factors and tamoxifen use to help clarify the mechanism behind the risk reduction.

Anti-oestrogenic chemoprevention of breast cancer-the need to progress

Clinical trials of the selective oestrogen receptor modulator (SERM), tamoxifen, have shown an early reduction in risk of breast cancer in healthy women of approximately 40%, but with associated risks and benefits to normal tissues. An overall clinical benefit and the identification of the women at risk of breast cancer who may gain benefit from tamoxifen has not been clearly established. The identification of those women at risk who are most likely to gain benefit, and the development of other SERMs and aromatase inhibitors which might be more active and have a more beneficial spectrum of activity on normal tissues in healthy women is essential, if the aim of preventing breast cancer in healthy women is to be achieved.

Anti-oestrogenic prevention of breast cancer--the make or break point

Clinical trials have shown that giving anti-oestrogens to healthy women can reduce the early incidence of breast cancer by approximately 40%. However, the large numbers of women treated, compared with the few who get breast cancer, together with the not insignificant toxicity and the unknown long-term clinical benefits and risks, makes this strategy of prevention versus treatment precarious. So how can we improve the odds for the successful use of endocrine chemoprevention?

High bone-mass density as a marker for breast cancer in post-menopausal women

Bone mass has been proposed as a marker of cumulative exposure to oestrogen in women. We have studied the association between bone mass and breast cancer in postmenopausal women. In 126 cases of breast cancers and 126 controls, the bone mineral density (BMD) of the lumbar spine (L2-L4), femoral neck, trochanter and Ward's triangle was measured by dual-energy X-ray absorptiometry. All cases of cancer were confirmed by pathological reports. A questionnaire including information on reproductive history and other variables was collected. BMD was significantly higher among breast cancer patients than controls at all sites, except at the femoral neck where BMD was increased in the cancer group, but not significantly. After adjustment for potential confounding factors, the estimated relative risk of breast cancer in the highest quartile of BMD compared to the lowest quartile ranged from 2.5 to 4.8 for various sites of measurement. These results confirm that bone-mass density is a strong predictor for breast cancer in postmenopausal women. Women in the lowest quartile of bone mass appear to be protected against breast cancer. The mechanisms underlying this relation may be explained by cumulative exposure to oestrogen.

Indicators of lifetime estrogen exposure: effect on breast cancer incidence and interaction with raloxifene therapy in the multiple outcomes of raloxifene evaluation study participants

PURPOSE

To test the hypothesis that risk factors related to lifetime estrogen exposure predict breast cancer incidence and to test if any subgroups experience enhanced benefit from raloxifene.

PATIENTS AND METHODS

Postmenopausal women with osteoporosis (N = 7,705), enrolled onto the Multiple Outcomes of Raloxifene Evaluation (MORE) trial, were randomly assigned to receive placebo, raloxifene 60 mg/d, or raloxifene 120 mg/d for 4 years. Breast cancer risk was analyzed by the following baseline characteristics indicative of estrogen exposure: previous hormone replacement therapy, prevalent vertebral fractures, family history of breast cancer, estradiol level, bone mineral density (BMD), body mass index, and age at menopause. Therapy-by-subgroup interactions were assessed using a logistic regression model.

RESULTS

Overall, women with the highest one-third estradiol levels (> or = 12 pmol/L) had a 2.07-fold increased invasive breast cancer risk compared with women with lower levels. Raloxifene significantly reduced breast cancer risk in both the low- and high-estrogen subgroups for all risk factors examined (P <.05 for each comparison). The women with the highest BMD and those with a family history of breast cancer experienced a significantly greater therapy benefit with raloxifene, compared with the two thirds of patients with lower BMD or those without a family history, respectively; the subgroup-by-therapy interactions were significant (P =.005 and P =.015, respectively).

CONCLUSION

The MORE trial confirms that increased lifetime estrogen exposure increases breast cancer risk. Raloxifene therapy reduces breast cancer risk in postmenopausal osteoporotic women regardless of lifetime estrogen exposure, but the reduction is greater in those with higher lifetime exposure to estrogen.