Radiation and cancer risk in atomic-bomb survivors

With the aim of accurately assessing the effects of radiation exposure in the Japanese atomic-bomb survivors, the Radiation Effects Research Foundation has, over several decades, conducted studies of the Life Span Study (LSS) cohort, comprising 93?000 atomic-bomb survivors and 27?000 controls. Solid cancer: the recent report on solid cancer incidence found that at age 70 years following exposure at age 30 years, solid cancer rates increase by about 35% Gy(-1) for men and 58%?Gy(-1) for women. Age-at-exposure is an important risk modifier. In the case of lung cancer, cigarette smoking has been found to be an important risk modifier. Radiation has similar effects on first-primary and second-primary cancer risks. Finally, radiation-associated increases in cancer rates appear to persist throughout life. Leukaemia: the recent report on leukaemia mortality suggests that radiation effects on leukaemia mortality persisted for more than 50 years. Moreover, significant dose-response for myelodysplastic syndrome was observed in Nagasaki LSS members even 40-60 years after radiation exposure. Future perspective: given the continuing solid cancer increase in the survivor population, the LSS will likely continue to provide important new information on radiation exposure and solid cancer risks for another 15-20 years, especially for those exposed at a young age.     

Breast cancer mortality and the change in fertility risk factors at menopause: a prospective study of 800,000 married Norwegian women

I examined breast cancer mortality in relation to fertility factors in a cohort of 800,814 married Norwegian women aged 25-74 years at the start of follow-up. Women aged 25-44 years with a first birth after the age of 35 years had a RR = 2.58 compared with women with a first birth before the age of 20 years. For women aged 45-74 years, the corresponding RR was 1.35. On the other hand, the rate differences between women with a late first birth (35+ years) and an early birth (less than 20 years) were similar for women of different ages. Small rate differences were found for premenopausal women between uniparous women and women with 6-7 children, but postmenopausal women with many children had lower rates of breast cancer mortality than uniparous women. For postmenopausal women the rate differences were stable over age categories. This study points toward a change in fertility risk factors at menopause.     

Breast cancer risk reduction: what do we know and where should we go?

Clinicians should be aware of the advances in breast cancer risk assessment and risk-reduction therapy. The modified Gail model is appropriate for predicting the risk of developing breast cancer within the next 5 years for most women between ages 35 and 75. Tamoxifen has been approved by the U.S. Food and Drug Administration (FDA) for reduction of breast cancer risk in women aged 35 and older who meet the threshold risk for breast cancer. Raloxifene is being compared with tamoxifen in the clinical trial, STAR (a Study of Tamoxifen and Raloxifene), which is now enrolling postmenopausal women aged 35 or older. The risks and benefits of therapy to reduce breast cancer risk are reviewed here. Processes for comparison of risks and benefits and for shared decision making are outlined.     

Risk factors for breast cancer in elderly women

As the population ages, an increasing fraction of women diagnosed with breast cancer will be elderly. Heterogeneity of breast cancer risk factors between pre- and postmenopausal women is recognized, but few studies have examined elderly women specifically. The authors describe the age-specific influence of risk factors for postmenopausal breast cancer, with emphasis on women aged 75 or more years. Among 36,658 members of the Iowa Women's Health Study (1986-2001), a population-based cohort study, 428 incident breast cancers were diagnosed in women aged 55-64 years, 1,297 in women aged 65-74 years, and 561 in women aged 75-84 years. Women with a body mass index (weight (kg)/height (m)(2)) in the highest versus the lowest quartile were at increased risk of breast cancer at age 75 or more years (adjusted hazard ratio = 1.44, 95% confidence interval (CI): 1.12, 1.84). Family history of breast cancer (hazard ratio = 1.54, 95% CI: 1.24, 1.93 for a first-degree family history vs. none) and an older age at menopause (p(trend) = 0.07) conferred increased risk for women aged 75 or more years, and a high number of livebirths was protective (hazard ratio = 0.67, 95% CI: 0.51, 0.88 for five or more births compared with one or two). Obesity, a modifiable risk factor, remained positively associated with breast cancer for all age groups of postmenopausal women.     

Influence of exercise activity on quality of life in long-term breast cancer survivors

Background: Behavioral and lifestyle factors may influence quality of life (QOL) outcomes in breast cancer survivors. Methods: Information on QOL (Short Form-36, SF-36), lifestyle and survivorship was collected during telephone interviews with 374 breast cancer patients, diagnosed between 1983 and 1988 at ages 40 years or younger and interviewed, on average 13.2 years following diagnosis. These women previously participated in a case-control study soon after their diagnoses, providing information on breast cancer risk factors including exercise activity. We examined the impact of changes in exercise activity (comparing pre- to post-diagnosis levels) on the SF-36 mental and physical health summary scales using regression analyses. Results: A positive change in exercise activity was associated with a higher score on the SF-36 physical health summary scale at follow-up (p= 0.005). Change in exercise activity was not associated with the SF-36 mental health summary scale score. Patients who increased their activity levels did not differ from those who did not in terms of medical or demographic characteristics. Conclusion: This study provides one of the longest follow-up periods of breast cancer survivors to date among studies that focus on QOL and is unique in its focus on women diagnosed at a young age. Our results confirm high levels of functioning and well-being among long-term survivors and indicate that women whose exercise activity increased following diagnosis score higher on the SF-36 physical health summary scale. These findings suggest a potential role for exercise activity in maintaining well-being after a cancer diagnosis.     

Differences in the timeliness of diagnosis, breast and cervical cancer, San Francisco 1974-85.

Cancer registry data for San Francisco (1974-85) were used to identify women at greater risk of late diagnoses for breast and cervical cancers by age and ethnicity. For breast cancer, Black women were at greater risk for late diagnoses. For cervical cancer, women of all ethnic groups ages 50-69 years and Japanese and Filipino women were at greater risk for late diagnoses.     

Anthropometric variables in relation to risk of breast cancer in middle-aged women

BACKGROUND: Many epidemiological studies have assessed the relationships between anthropometric variables and breast cancer risk. However, methodological approaches for analysing these factors differ appreciably. Also, age when maximum height is achieved has been identified as a potential risk factor for breast cancer in premenopausal women, but this issue has not been studied in postmenopausal women. METHODS: The participants in this population-based case-control study were postmenopausal women 50-64 years of age from the general female population of western Washington State. It included 479 women with incident primary breast cancer and 435 controls. RESULTS: This study found that: (i) women who gained over 70 pounds since age 18 had an increased risk of breast cancer relative to those who stayed within 10 pounds of their weight at age 18 (odds ratio [OR] = 2.7; 95% CI: 1.5-4.9), (ii) women with body mass indices (BMI) below what is considered healthy had a decreased risk (OR = 0.4; 95% CI: 0.2-1.1) while women with a BMI in the obese range had an increased risk of breast cancer (OR = 1.4; 95% CI: 1.0-2.1), and (iii) women who reached their maximum height at or after the age of 18 had a decreased risk of breast cancer compared to women who reached their maximum height at age 13 or younger (OR = 0.7; 95% CI: 0.5-1.0). CONCLUSIONS: By examining various anthropometric variables using clinically relevant strata, a clearer picture of how these variables relate to postmenopausal breast cancer risk was developed. Similar to younger women, postmenopausal women who reached their maximum height at later ages had a decreased risk of breast cancer.     

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.     

Breast cancer in two populations with different levels of risk for the disease

Caucasian women in Hawaii have a higher risk for breast cancer than women of Japanese ancestry. In order to determine to what extent known risk factors account for the difference in risk between the two groups, a case-control study was done from 1975 to 1980. A total of 183 Japanese and 161 Caucasian breast cancer cases were interviewed along with their respective controls. The findings suggested that a positive history of benign breast disease, a family history of breast cancer, late menopause, late age at first childbirth and early age at menarche did not fully account for the difference in breast cancer risk between Caucasian and Japanese women in Hawaii. Attention needs to be focused on other factors that are under environmental influence.     

Fruit and vegetable intake in relation to risk of breast cancer in the Black Women's Health Study

The authors prospectively examined the relation of fruit and vegetable intake to breast cancer risk among 51,928 women aged 21-69 years at enrollment in 1995 in the Black Women's Health Study. Dietary intake was assessed by using a validated food frequency questionnaire. Cox proportional hazards models were used to estimate incidence rate ratios and 95% confidence intervals, adjusted for breast cancer risk factors. During 12 years of follow-up, there were 1,268 incident cases of breast cancer. Total fruit, total vegetable, and total fruit and vegetable intakes were not significantly associated with overall risk of breast cancer. However, total vegetable consumption was associated with a decreased risk of estrogen receptor-negative/progesterone receptor-negative breast cancer (incidence rate ratio = 0.57, 95% confidence interval: 0.38, 0.85, for ≥2 servings/day relative to <4/week; P(trend) = 0.02). In addition, there was some evidence of inverse associations with breast cancer risk overall for cruciferous vegetable intake (P(trend) = 0.06) and for carrot intake (P(trend) = 0.02). Study findings suggest that frequent consumption of vegetables is inversely associated with risk of estrogen receptor-negative/progesterone receptor-negative breast cancer, and that specific vegetables may be associated with a decreased risk of breast cancer overall.     

A prospective cohort study of postmenopausal hormone use and risk of breast cancer in US women

The association between history of postmenopausal hormone use as of 1976 and breast cancer incidence during 1976-1980 was examined prospectively among 33,335 married, postmenopausal registered nurses aged 30-55 years at entry. Half the women reported postmenopausal hormone use, and one fourth had taken these drugs for over five years. During 1976-1980, 221 new cases of breast cancer were identified. The relative risk (RR) for those who had used postmenopausal hormones when compared with women who had never used them was 1.1 (95% confidence limits (CL) 0.8, 1.4); for current and past users, the relative risks were 1.0 (95% CL 0.7, 1.4) and 1.3 (95% CL 0.9, 1.8), respectively. These ratios were not substantially modified by whether or not a woman's ovaries had been removed or by other known breast cancer risk factors. No increase in breast cancer risk was apparent among women who had used postmenopausal hormones for less than five years (RR = 1.0, 95% CL 0.5, 1.6). An apparent effect among the subgroup of women who had used them for five to nine years (RR = 1.5, 95% CL 1.0, 2.2) was not present among the few women with longer-term use (RR = 0.9, 95% CL 0.4, 1.6). These findings are moderately reassuring, but since there are as yet few women in this cohort with long-term durations of use and, particularly, with long intervals since first use, continued follow-up of this and other cohorts will be required before firm conclusions can be drawn, especially among specific subgroups.     

Factors Related to Return to Work by Women with Breast Cancer in Northern France

Introduction Earlier diagnosis and better treatment have increased the survival rates of breast cancer patients. This warrants research on return to work of cancer survivors, especially about subjective factors because they affect the mental desire to return to work. Moreover, knowledge in this issue is very limited in France. Objectives This study aims to explore the objective and subjective factors that affect whether and when women with breast cancer return to work. Methods 379 women with breast cancer aged 18–60 years who were working at the time of diagnosis responded to a 45 item questionnaire. The questionnaire had personal characteristics, disease-related characteristics and work-related ones. Multivariate logistic regressions were run to determine the association of these factors and return to work and time until return to work. Results During a median follow-up of 36 months, 82.1% of the 379 women who had worked before their diagnosis returned to work after a median sick leave of 10.8 months. Older age, lower educational level, chemotherapy, radiotherapy, lymphoedema, psychological or organizational self-perceived constraints related to their former job, and the lack of moral support from work colleagues both limited and delayed return to work. Conclusion The resumption of work by women with breast cancer depends on many factors, not all of them medical. The self-perceived factors must be considered: first to help support these women during their sick leave, while taking into account elements that may hinder early return to work; second to initiate a work resumption support process which takes into account both the person and her environment.     

Effect of the Lifestyle,Exercise, and Nutrition (LEAN) Study on Long-Term Weight Loss Maintenance in Women with Breast Cancer

Lifestyle interventions among breast cancer survivors with obesity have demonstrated successful short-term weight loss, but data on long-term weight maintenance are limited. We evaluated long-term weight loss maintenance in 100 breast cancer survivors with overweight/obesity in the efficacious six-month Lifestyle, Exercise, and Nutrition (LEAN) Study (intervention = 67; usual care = 33). Measured baseline and six-month weights were available for 92 women. Long-term weight data were obtained from electronic health records. We assessed weight trajectories between study completion (2012–2013) and July 2019 using growth curve analyses. Over up to eight years (mean = 5.9, SD = 1.9) of post-intervention follow-up, both the intervention (n = 60) and usual care (n = 32) groups declined in body weight. Controlling for body weight at study completion, the yearly weight loss rate in the intervention and usual care groups was –0.20 kg (−0.2%/year) (95% CI: 0.06, 0.33, p = 0.004) and −0.32 kg (−0.4%/year) (95% CI: 0.12, 0.53, p = 0.002), respectively; mean weight change did not differ between groups (p = 0.31). It was encouraging that both groups maintained their original intervention period weight loss (6% intervention, 2% usual care) and had modest weight loss during long-term follow-up. Breast cancer survivors in the LEAN Study, regardless of randomization, avoided long-term weight gain following study completion.     

Mammographic screening: keeping women alive

Evaluation of: Tabár L, Vitak B, Chen TH et al. Swedish Two-County Trial: impact of mammographic screening on breast cancer mortality during 3 decades. Radiology 260(3), 658-663 (2011). In the 1980s, the periodic invitation of women aged 40-69 years for mammographic screening in the Swedish Two-County Trial showed a strong 30% reduction in breast cancer mortality. The result of 2-3-yearly mammographic examinations has persisted throughout the long follow-up of three decades. Through the richness of the collected and verified data, the trial has also demonstrated a substantial and absolute reduction in mortality risk. For each 414 women screened for 7 years (approximately four screening examinations), one breast cancer death was prevented. Transferring these outcomes to, for example, the national program of the UK, for every 1000 women aged 47-73 years attending the 3-yearly screenings (nine screening examinations) at least five to seven breast cancer deaths would be prevented. In recent follow-up papers by the Swedish trial group, the major human cost of screening (false-positive outcome, occurrence of interval cancer, overdiagnosis and radiation exposure) were judged to be in balance with the accurately demonstrated mortality benefit.     

Interaction between smoking and obesity and the risk of developing breast cancer among postmenopausal women: the Women's Health Initiative Observational Study

Obesity is a well-established risk factor for postmenopausal breast cancer. Recent studies suggest that smoking increases the risk of breast cancer. However, the effect of co-occurrence of smoking and obesity on breast cancer risk remains unclear. A total of 76,628 women aged 50-79 years enrolled in the Women's Health Initiative Observational Study were followed through August 14, 2009. Cox proportional hazards regression models were used to estimate hazard ratios and 95% confidence intervals. Over an average 10.3 years of follow-up, 3,378 incident cases of invasive breast cancer were identified. The effect of smoking on the risk of developing invasive breast cancer was modified significantly by obesity status among postmenopausal women, regardless of whether the obesity status was defined by body mass index (P(interaction) = 0.01) or waist circumference (P(interaction) = 0.02). A significant association between smoking and breast cancer risk was noted in nonobese women (hazard ratio = 1.25, 95% confidence interval: 1.05, 1.47) but not in obese women (hazard ratio = 0.96, 95% confidence interval: 0.69, 1.34). In conclusion, this study suggests that the effect of smoking exposure on breast cancer risk was modified by obesity among postmenopausal women. The modification effect did not differ by general versus abdominal obesity.     

Using a Delphi technique to determine the needs of African American breast cancer survivors

A qualitative study was designed in collaboration with the Sisters Network, Inc., the only nonprofit national Black breast cancer support group, to identify the needs of Black breast cancer survivors. This article describes the use of the Delphi technique as a methodological tool for listening to culturally different speakers and building consensus among members of a racial minority group regarding their most important needs as breast cancer survivors. The specific objective of the study was to determine if the seldom-used Delphi technique could serve as a tool for deriving consensus on a significant health care concern among members of a racial minority group. Sixty-two survivors from different geographical regions of the United States participated in the study. The Delphi technique proved to be a useful qualitative method for encouraging discussion among a group of women with a vested interest in a specific health issue.     

The independent associations of parity, age at first full term pregnancy, and duration of breastfeeding with the risk of breast cancer. Cancer and Steroid Hormone Study Group

Although the important influence of a woman's reproductive history on her risk of breast cancer is widely recognized, it is not clear whether this is wholly accounted for by the age at her first full-term pregnancy, or whether there are additional, independent influences of breastfeeding or number of children. To examine the respective contributions to the risk of breast cancer of these reproductive factors, we used logistic regression methods to analyze data from a multicenter case-control study, the Cancer and Steroid Hormone Study. Included in the analysis were 4599 women, 20-55 years of age, identified as having an initial diagnosis of breast cancer by one of eight collaborating population-based cancer registries. The 4536 controls were women of similar ages selected by random dialing of households with telephones in the same eight areas. As expected, age at first full-term pregnancy exerted a strong influence on the risk of breast cancer. However, after it and other potentially confounding factors had been controlled for, parity and duration of breastfeeding also had a strong influence on the risk of breast cancer. Compared with women of parity one, women of parity seven or greater had an adjusted relative risk of breast cancer of 0.59 (95% CL, 0.44-0.79). Compared with parous women who never breastfed, women who had breastfed for 25 months or more had an adjusted relative risk of 0.67 (0.52-0.85). These results do not support the supposed preeminent importance of age at first full-term pregnancy among the reproductive determinants of breast carcinogenesis. Resolution of this issue may have important implications for elucidating hormonal influences on breast cancer and for projecting future trends in the disease.     

Breast Cancer and Sexuality

Breast cancer is the most common form of cancer among women today. With early detection and advanced treatment options, survival rates are continuing to improve, but not without some long-term physical and emotional side effects. This article reviews the effects of breast cancer in general and breast cancer treatment specifically on sexuality in cancer survivors. How the cancer and its treatment may affect women at different ages is discussed. The psychological impact of cancer therapy on both the patient and her spouse are noted; and options for treatment interventions are reviewed.     

Obesity/Weight Gain and Breast Cancer Risk: Findings From the Japan Collaborative Cohort Study for the Evaluation of Cancer Risk

Background

We analyzed data from the Japan Collaborative Cohort Study (36 164 women aged 40–79 years at baseline in 1988–1990 with no previous diagnosis of breast cancer and available information on weight and height) to examine the association between baseline body mass index (BMI)/weight gain from age 20 years and breast cancer risk in a non-Western population.

Methods

The participants were followed prospectively from enrollment until 1999–2003 (median follow-up: 12.3 years). During follow-up, breast cancer incidence was mainly confirmed through record linkage to population-based cancer registries. A Cox proportional hazards model was used to calculate hazard ratios (HRs) and 95% CIs for the association between breast cancer risk and body size.

Results

In 397 644.1 person-years of follow-up, we identified 234 breast cancer cases. Among postmenopausal women, the adjusted HR increased with BMI, with a significant linear trend (P < 0.0001). Risk was significantly increased among women with a BMI of 24 or higher (HR: 1.50, 95% CI: 1.09–2.08 for BMI of 24–28.9, and 2.13, 1.09–4.16 for BMI ≥ 29) as compared with women with a BMI of 20 to 23.9. Weight gain after age 20 years and consequent overweight/obesity were combined risk factors for postmenopausal breast cancer risk. This combined effect was stronger among women aged 60 years or older. However, the HRs were not significant in premenopausal women.

Conclusions

Our findings support the hypothesis that weight gain and consequent overweight/obesity are combined risk factors for breast cancer among postmenopausal women, particularly those aged 60 years or older.Key words: breast cancer, obesity, weight gain, cohort study     

Using qualitative methods to elicit recall of a critical time period

The period during and after puberty seems to be important for breast cancer initiation. Because experiences during that time are likely to be influenced by a woman's cultural background, we conducted a pilot study among Hispanic and Caucasian women to elicit their memories of early life events. These data were used to design culture-specific questionnaire modules for the retrospective assessment of peripubertal breast cancer risk factors, using specific strategies to trigger accurate recall. Study subjects were volunteer breast cancer survivors or relatives of survivors. In carrying out this work, we took methods from the social sciences and applied them to a research question in chronic disease epidemiology. We found both qualitative and quantitative differences in recall of peripubertal exposures and experiences between Hispanic and Caucasian subjects. Our preliminary data indicate that in contrast to Caucasian women, Hispanic women consider the church rather than school a touchstone for recalling past events. Under the domain "body development," Hispanic women are more likely to mention menstruation than Caucasian women but less likely to recall changes in body hair and breast development. Caucasian women cited team sports as an important physical activity during the peripubertal period, whereas Hispanic women listed more sedentary games and housework as the main activities. Results of our pilot study support the view that to enhance the validity of retrospective data on peripubertal breast cancer risk factors, it is important to take account of cultural differences. Our experience using qualitative methods to elicit data of this kind in the context of a larger epidemiologic research effort suggests that such innovative approaches are valuable.