The relationship between age and incidence of breast cancer. Population and screening program data

Mammary stem cells and progenitors: targeting the roots of breast cancer for prevention

Breast cancer prevention is daunting, yet not an unsurmountable goal. Mammary stem and progenitors have been proposed as the cells-of-origin in breast cancer. Here, we present the concept of limiting these breast cancer precursors as a risk reduction approach in high-risk women. A wealth of information now exists for phenotypic and functional characterization of mammary stem and progenitor cells in mouse and human. Recent work has also revealed the hormonal regulation of stem/progenitor dynamics as well as intrinsic lineage distinctions between mammary epithelial populations. Leveraging these insights, molecular marker-guided chemoprevention is an achievable reality.

Change in mammographic density across birth cohorts of Dutch breast cancer screening participants

High mammographic density is a well‐known risk factor for breast cancer. This study aimed to search for a possible birth cohort effect on mammographic density, which might contribute to explain the increasing breast cancer incidence. We separately analyzed left and right breast density of Dutch women from a 13‐year period (2003–2016) in the breast cancer screening programme. First, we analyzed age‐specific changes in average percent dense volume (PDV) across birth cohorts. A linear regression analysis (PDV vs. year of birth) indicated a small but statistically significant increase in women of: 1) age 50 and born from 1952 to 1966 (left, slope = 0.04, p = 0.003; right, slope = 0.09, p < 0.0001); 2) age 55 and born from 1948 to 1961 (right, slope = 0.04, p = 0.01); and 3) age 70 and born from 1933 to 1946 (right, slope = 0.05, p = 0.002). A decrease of total breast volume seemed to explain the increase in PDV. Second, we compared proportion of women with dense breast in women born in 1946–1953 and 1959–1966, and observed a statistical significant increase of proportion of highly dense breast in later born women, in the 51 to 55 age‐groups for the left breast (around a 20% increase in each age‐group), and in the 50 to 56 age‐groups for the right breast (increase ranging from 27% to 48%). The study indicated a slight increase in mammography density across birth cohorts, most pronounced for women in their early 50s, and more marked for the right than for the left breast.

What's new?

Women with dense breast tissue are at increased risk of breast cancer. Here, changes in mammographic density were investigated across birth cohorts in women enrolled in a breast cancer screening program in the Netherlands. The findings reveal an increase in the average fraction of dense tissue in the breast across cohorts. In particular, greater breast density was observed in a higher proportion of women in later‐born than earlier‐born birth cohorts. The increase was most significant among women in their early 50s and may be linked to a reported shift toward older age at menopause among women in Europe.

Synthesis and antitumor activity of new D-seco and D-homo androstane derivatives

Starting from 3beta-hydroxy-17-oxo-16,17-secoandrost-5-ene-16-nitrile (1), the new 16,17-secoandrostane derivatives 4-9 were synthesized. On the other hand, 3beta-hydroxy-17-oxa-D-homoandrost-5-ene-16-one (10) yielded the new d-homo derivatives 12, 13 and 15. In vitro antiproliferative activity of selected compounds against three tumor cell lines (human breast adenocarcinoma ER+, MCF-7, human breast adenocarcinoma ER-, MDA-MB-231, prostate cancer AR-, PC-3, and normal fetal lung fibroblasts, MRC-5) was evaluated. Compounds 3 and 12 showed strong antiproliferative activity against PC-3 cells, the IC(50) values being 2 microM and 0.55 microM, respectively. Compounds 6 (10 microM) and 14 (9 microM) showed moderate activity against MDA-MB-231 cells. The synthesized compounds 1-3, 5-8, 10 and 12-15 were not toxic to normal fetal lung fibroblasts cells, MRC-5.

The epidemiology of arm and hand swelling in premenopausal breast cancer survivors

BACKGROUND

Breast cancer survivors suffer from lymphedema of the arm and/or hand. Accurate estimates of the incidence and prevalence of lymphedema are lacking, as are the effects of this condition on overall quality of life.

METHODS

Six hundred twenty-two breast cancer survivors (age, <or=45 years at diagnosis) were followed with semiannual questionnaires for 36 months after surgery to determine the incidence of lymphedema, prevalence of persistent swelling, factors associated with each, and quality of life.

RESULTS

Of those contacted and eligible for the study, 93% agreed to participate. Fifty-four percent reported arm or hand swelling by 36 months after surgery, with 32% reporting persistent swelling. Swelling was reported to occur in the upper arm (43%), the hand only (34%), and both arm and hand (22%). Factors associated with an increased risk of developing swelling included having a greater number of lymph nodes removed [hazards ratio (HR), 1.02; P < 0.01], receiving chemotherapy (HR, 1.76; P = 0.02), being obese (HR, 1.51 versus normal weight; P = 0.01), and being married (HR, 1.36; P = 0.05). Factors associated with persistent swelling were having more lymph nodes removed (odds ratio, 1.03; P = 0.01) and being obese (odds ratio, 2.24 versus normal weight; P < 0.01). Women reporting swelling had significantly lower quality of life as measured by the functional assessment of cancer therapy-breast total score and the SF-12 physical and mental health subscales (P < 0.01 for each).

CONCLUSIONS

Lymphedema occurs among a substantial proportion of young breast cancer survivors. Weight management may be a potential intervention for those at greatest risk of lymphedema to maintain optimal health-related quality of life among survivors.

Retrospective study of the effect of comorbidity on use of adjuvant chemotherapy in older women with breast cancer in a tertiary care setting

Use of adjuvant chemotherapy for breast cancer decreases with increasing age. We examined the effect of comorbidity on adjuvant chemotherapy use in older women (age >55 years) in a tertiary care Oncology Clinic. Clinic charts of new, early stage breast cancer patients over age 55 were reviewed. Multivariate analysis was used to determine the effect of age (55-64 versus > or =65 years), tumor stage, and comorbidity (Charlson score) on management. Two hundred and seventy-three charts were reviewed. Older women had a greater mean Charlson comorbidity score (0.72 versus 0.21; p<0.001). Tamoxifen use was similar in both groups (82.8% versus 81.1%, p=0.72). Chemotherapy was less frequently used in older women, regardless of nodal status: overall, 13.1% versus 45.6%, p<0.001; node-negative, 8.2% versus 32.1%, p<0.001; and node-positive, 25% versus 83.8%, p<0.001. In a multivariate analysis, lower stage, older age, and higher comorbidity were predictive of less frequent use of adjuvant chemotherapy. Though higher comorbidity was associated with less use of adjuvant chemotherapy, it did not totally account for the low use of chemotherapy in older compared to younger women. More work should be planned to dissect out specific reasons for differences in treatment by age.

Potent CYP19 (Aromatase) 1-[(Benzofuran-2-yl)(phenylmethyl)pyridine, -imidazole, and -triazole Inhibitors: Synthesis and Biological Evaluation

The synthesis of a series of novel 1-[(benzofuran-2-yl)phenylmethyl]-pyridine, -imidazole, and -triazole derivatives is described. All the compounds were evaluated in vitro for inhibitory activity against aromatase (P450(AROM), CYP19), using human placental microsomes. The 6-methoxy- and 6-hydroxy-substituted benzofuran derivatives were shown to be potent CYP19 inhibitors (IC(50) = 0.01-1.46 microM) with activity greater than that observed for the unsubstituted parent compounds and inhibitory activity comparable with or greater than the reference compound arimidex (IC(50) = 0.6 microM). Six of the benzofuran derivatives were subjected to in vitro cytotoxicity assays, using rat liver hepatocytes with cytotoxicity determined from alteration in cell morphology and lactate dehydrogenase enzyme retention over a period of 24 h, and selectivity (CYP17, 17beta-HSD types 1 and 3, CYP24, and CYP26) determination; negligible inhibitory activity was observed, suggesting a good selectivity for CYP19. The pyridine benzofuran 4a containing the 4-fluorophenyl group was the most promising (IC(50) = 44 nM; LC(50) >100 microM) compared with arimidex (IC(50) = 600 nM; LC(50) > 200 microM).

An overlooked connection: serotonergic mediation of estrogen-related physiology and pathology

BACKGROUND

In humans, serotonin has typically been investigated as a neurotransmitter. However, serotonin also functions as a hormone across animal phyla, including those lacking an organized central nervous system. This hormonal action allows serotonin to have physiological consequences in systems outside the central nervous system. Fluctuations in estrogen levels over the lifespan and during ovarian cycles cause predictable changes in serotonin systems in female mammals.

DISCUSSION

We hypothesize that some of the physiological effects attributed to estrogen may be a consequence of estrogen-related changes in serotonin efficacy and receptor distribution. Here, we integrate data from endocrinology, molecular biology, neuroscience, and epidemiology to propose that serotonin may mediate the effects of estrogen. In the central nervous system, estrogen influences pain transmission, headache, dizziness, nausea, and depression, all of which are known to be a consequence of serotonergic signaling. Outside of the central nervous system, estrogen produces changes in bone density, vascular function, and immune cell self-recognition and activation that are consistent with serotonin's effects. For breast cancer risk, our hypothesis predicts heretofore unexplained observations of the opposing effects of obesity pre- and post-menopause and the increase following treatment with hormone replacement therapy using medroxyprogesterone.

SUMMARY

Serotonergic mediation of estrogen has important clinical implications and warrants further evaluation.

Reduced mammographic screening may explain declines in breast carcinoma in older women

OBJECTIVES

To examine whether declines in breast cancer in the oldest-old women correspond with declines in the use of cancer testing.

DESIGN

Cross-sectional evaluation of three databases.

SETTING

Public access data.

PARTICIPANTS

Cases recorded in the California Registry and the Surveillance, Epidemiology, and End Results Program between 1988 and 1997. The study also included respondents to the 2002 Centers for Disease Control and Prevention Behavioral Risk Factor Surveillance System.

MEASUREMENTS

Cancer incidence and self-reported mammography within the previous 2 years.

RESULTS

Most previous analyses have combined all individuals aged 75, 80, or 85 and older. Creating separate categories for age ranges 85 to 89, 90 to 94, 95 to 99, and 100 and older suggests different incidence patterns for a variety of cancers, including mammary carcinoma in situ (CIS). Between the ages of 40 and 74, there is a significant rise in CIS. Beginning at age 75, there is a significant decline in CIS through the highest age categories. The use of mammographic screening increases between the ages of 40 and 60. Beginning at age 75, there is a significant decline in the use of mammography that parallels the decline in incident cases of CIS.

CONCLUSION

There may be a substantial reservoir of undiagnosed CIS in the population. Surveillance bias might explain the decreasing incidence of CIS with advancing age in the oldest age groups. Autopsy studies are needed to estimate the true prevalence of CIS in older women.

Incidence of Invasive Breast Cancer and Ductal Carcinoma In situ in a Screening Program by Age: Should Older Women Continue Screening?

Objective: The evidence for the effectiveness of screening is strongest for women ages 50 to 69 years; however, there is variation in the target age group for screening programs between different countries. In particular, there is uncertainty over whether women should continue screening once they reach age 70. We therefore investigated incidence rates for invasive and in situ breast cancer by age as well as prognostic features of tumors within a screening program. Methods: We studied 474,808 women who attended BreastScreen Victoria from January 1, 1993 to December 31, 2000. Of these women, 5,301 were diagnosed with invasive cancer and 1,127 were diagnosed with ductal carcinoma in situ. We used generalized additive models to model age-incidence rates for invasive cancers and ductal carcinoma in situ separately by users and nonusers of hormone replacement therapy at most recent screen. Nonparametric trends for ordered groups and regression methods were used to investigate trends in size, grade, and nodal involvement for invasive tumors by type of attendance and time since previous negative screen for age group. Results: The incidence of ductal carcinoma in situ among women with a previous negative screen clearly declined after age 70 irrespective of hormone replacement therapy use. At subsequent screen, the age-incidence curve for invasive breast cancer flattened at ages 60 to 75 years and then increased only for women taking hormone replacement therapy. Tumor size at diagnosis declined with age at both first round (P = 0.15) and subsequent round (P = 0.08). The proportion of poorly differentiated tumors also decreased with age, with the smallest proportion of grade III tumors diagnosed in women ages ≥75 years (P = 0.09 for first screen and P = 0.05 for subsequent screen). The presence of positive nodes at diagnosis declined with age (P &lt; 0.001) for both first and subsequent screening rounds. Conclusion: Older age is associated with more favorable prognostic tumor features and a lower incidence of ductal carcinoma in situ among subsequent attenders of screening. When making decisions regarding continuing screening, older women and their physicians should also consider the presence of other comorbid conditions that may mitigate any impact of screening on mortality.

Updates in surgical oncology for elderly patients

Elderly patients affected by solid tumours are frequently encountered on the surgical ward. Prejudice regarding operative risks and long term outcomes may alter their surgical management. Large series of elderly cancer subjects have been analysed and conclusive data are now available, to better tailor their management. Specific epidemiological data are presented in this review, screening programs critically considered, treatment procedures discussed, and the effectiveness of follow-up protocols is analysed together with cost effectiveness issues. Quality of life issues should not be neglected, and a continuous educational endeavour targeted at specialists and general practitioners is desirable.

Breast cancer and aging. Clinical interactions

The incidence and mortality rates of breast cancer increase with age. As the geriatric population grows, the number of breast cancer cases will reach epidemic proportions. The number of coexisting medical conditions also increases with advancing age. The presence and severity of comorbid conditions influences an individual's ability to tolerate procedures and treatments and must be considered in making disease-management decisions. Screening mammography can potentially save lives in older women. Women whose life expectancy exceeds 5 years should continue annual screening mammography. Choices for local definitive therapy, systemic adjuvant therapy, and treatment of metastatic disease should be based on patient preference and ability to tolerate the planned procedure. In general, otherwise healthy older women should be offered the same treatment options given to younger, postmenopausal women. Alternative, less aggressive, or nonstandard approaches are warranted in women whose life expectancy is limited or who are unable or unwilling to undergo standard management procedures.

An overview of breast cancer

Breast cancer is a major health problem in many parts of the world. Its impact in Saudi Arabia will be more obvious when the national data is released from the National Cancer Registry (NCR) in the near future. It is the most common cancer referred to the King Faisal Specialist Hospital and Research Centre (KFSH&RC). This is a retrospective review of all female breast cancer cases treated at KFSH&RC over a 15-year period. Patients were divided into two groups at the time of their referral to KFSH&RC: metastatic and nonmetastatic. We describe the demographic data, cancer-related information and the treatments offered to all patients. Comparisons were made between Saudi and non-Saudi, and the Saudis were examined in relation to their region of referral and observed to see if any changes occurred during the study period. As well, we tried to compare our results with experience elsewhere. A total of 1584 female breast cancer patients were treated at KFSH&RC between 1975 and 1991. Early breast cancer (Stages I, II) represented 36%, while 64% presented with advanced or metastatic disease (Stages III, IV). The majority of patients were premenopausal (64%). For patients with Stages I-III (1005), mastectomy was performed in 85% and lymph node dissection in 93%. Only 30% had no pathologic lymph node involvement and in 49% of the patients, lymph node dissection was adequate (>/= 10 nodes removed). Estrogen and progesterone receptors were known in 30% of the patients. Sixty-two percent and 72% of patients referred from the central region and the northern region had Stages II and III, respectively. For the non-Saudis, we observed more premenopausal patients (76%) and fewer Stage III. At 15 years, the relapse-free survival in Stages I, II and III was 33%, 36% and 18%, and the overall survival was 80%, 64% and 45%, respectively. Breast cancer in this population affects younger patients (premenopausal) and a higher proportion present with metastatic or locally advanced disease. Management strategies should incorporate conservative surgery when appropriate, and adequate lymph node dissection. This should be coupled with increasing public awareness and education and institution of screening programs. Overall survival is clearly linked to the stage of the disease.

Serum vitamin E level in patients with breast cancer

In this study, the serum vitamin E (total tocopherol) levels in patients with breast cancer (n = 100) and healthy controls (n = 70) were measured. The mean values for vitamin E were found to be 0.44 mg/100 ml in breast cancer patients and 1.108 mg/100 ml in controls. In the statistical evaluation, the vitamin E levels in breast cancer patients are significantly lower than in the controls (P < 0.05). The influence of factors such as suckling period, age of first gestation, smoking status and dietary habits were also studied.

Tumor suppressor p53 mutations and breast cancer: a critical analysis

Alterations in the tumor suppressor gene p53 are the most commonly identified changes in cancer, including neoplasia of the breast. The activity of p53 is regulated post-translationally. Phosphorylation state, subcellular localization, and interaction with any of a number of cellular proteins are likely to influence the function of p53. The exact effect of p53-mediated growth suppression seems to be cell-type specific but appears to be directly related to the ability of p53 to act as a specific transcriptional activator. The role that transcriptional repression plays in the function of WT p53 is less clear. It is also possible that p53 has a more direct activity in DNA replication and repair. Most documented p53 mutations result in single amino acid substitutions which may confer one or more of a spectrum of transforming abilities on the protein. Mutation may lead to nuclear accumulation of p53 protein; however, inactivation of p53 by nuclear exclusion and interaction with the mdm2 protein also appear to be important in tumorigenesis. Used in conjunction with other established factors, accumulation of cellular p53 may be a useful prognostic indicator in breast cancer. A syngeneic mouse model system yielded evidence that p53 mutations are important in the early, preneoplastic stages of mammary tumorigenesis. This murine system may provide the ability to investigate the functions of p53 in the early stages of breast cancer which are technically difficult to examine in the human system.

The relationship of breast cancer epidemiology to screening recommendations

The epidemiology of breast cancer involves several factors that may be useful in deciding to recommend breast cancer screening. Paramount among these factors is age. A family history of breast cancer may be a basis for modifying screening recommendations, but this may be appropriate only for a subset of women with breast cancer in a relative. Although there are several known risk factors for breast cancer, no single factor accounts for a large proportion of disease, and many patients with breast cancer have none of the recognized risk factors. A decision to forgo screening based on the absence of any single factor other than age may not be justified by current epidemiologic knowledge.

Toward a molecular understanding of human breast cancer: a hypothesis

A rate limiting step in most metastatic breast cancers is the development of unlimited proliferative potential by mammary epithelial cells. We describe mechanisms by which these cells can attain this state. The two independent mortality mechanisms controlling fibroblast senescence and immortalization (M1 and M2) are also found in human mammary epithelial cells. However, although both p53 and Rb are involved in the M1 mechanism of fibroblast cellular senescence, in human mammary epithelial cells only p53 is involved. The M1/M2 mechanisms may be induced by the gradual loss of telomere ends that occur as normal cells divide. Loss of telomere ends may result in genomic instability and in altered gene expression due to heterochromatin changes in subtelomeric regions. Events which can abrogate p53 functions are described, as is the current state of knowledge about the function of p53. All these factors are included in a molecular model for the onset of breast cancer.

Breast cancer risk factors. Contributions to planning breast cancer control

The analytic epidemiology of breast cancer has identified several risk factors that may be the bases for developing preventive interventions and refining screening guidelines. Breast cancer risk factors include both personal and environmental sources of risk. The available data, however, do not yet support the feasibility of large scale preventive interventions. Controlled trials will be needed to assess the effectiveness of those approaches. Knowledge of risk factors may be used by physicians to tailor their recommendations for individual patients. Risk factor data also may be used to modify screening recommendations for special populations. A family history of breast cancer may be a basis for modifying screening recommendations but this may be appropriate only for a subset of women with breast cancer in a relative.