Qualitative age interactions in breast cancer studies: mind the gap

Breast density reduction as a predictor for prognosis in premenopausal women with estrogen receptor-positive breast cancer: an exploratory analysis of the updated ASTRRA study

BACKGROUND

While the relationship between mammographic breast density reduction (MDR) and endocrine therapy efficacy has been reported in estrogen receptor (ER)-positive breast cancer, it is still unclear in premenopausal women, especially in the case of adding ovarian function suppression (OFS) to antihormone therapy. The authors investigated the impact of MDR on prognosis stratified by treatment based on the updated results of the ASTRRA trial.

MATERIALS AND METHODS

The ASTRRA trial, a randomized phase III study, showed that adding OFS to tamoxifen (TAM) improved survival in premenopausal women with estrogen receptor-positive breast cancer after chemotherapy. The authors updated survival outcomes and assessed mammography before treatment and the annual follow-up mammography for up to 5 years after treatment initiation. Mammographic density (MD) was classified into four categories based on the Breast Imaging-Reporting and Data System. MDR-positivity was defined as a downgrade in MD grade on follow-up mammography up to 2 years after randomization, with pretreatment MD grade as a reference.

RESULTS

The authors evaluated MDR in 944 of the 1282 patients from the trial, and 813 (86.2%) had grade III or IV MD. There was no difference in the MDR-positivity rate between the two treatment groups [TAM-only group (106/476 (22.3%)) vs. TAM+OFS group (89/468 (19.0%)); P =0.217). MDR-positivity was significantly associated with better disease-free survival (DFS) in the TAM+OFS group (estimated 8-year DFS: 93.1% in MDR-positive vs. 82.0% in MDR-negative patients; HR: 0.37; 95% CI: 0.16-0.85; P =0.019), but not in the TAM-only group ( Pinteraction =0.039). MDR-positive patients who received TAM+OFS had a favorable DFS compared to MDR-negative patients who received only TAM (HR: 0.30; 95% CI: 0.13-0.70; P =0.005).

CONCLUSION

Although the proportion of MDR-positive patients was comparable between both treatment groups, MDR-positivity was independently associated with favorable outcomes only in the TAM+OFS group.

Influence of age as a continuous variable on the prognosis of patients with pT1-2N1 breast cancer

PURPOSE

To assess the influence of age as a continuous variable on the prognosis of pT1-2N1 breast cancer and examine its decision-making value for postmastectomy radiotherapy (PMRT).

METHODS

We retrospectively evaluated 5438 patients with pT1-2N1 breast cancer after mastectomy in 11 hospitals. A multivariable Cox proportional hazards regression model with penalized splines was used to examine the relationship between age and oncologic outcomes.

RESULTS

The median follow-up was 67.0 months. After adjustments for confounding characteristics, nonsignificant downward trend in locoregional recurrence (LRR) risk was observed with increasing age (P-non-linear association = 0.640; P-linear association = 0.078). A significant non-linear association was found between age and disease-free survival (DFS) and overall survival (OS) (P-non-linear association <0.05; P-linear association >0.05, respectively). The DFS and OS exhibited U-shaped relationships, with the hazard ratios (HRs), reaching a nadir at 50 years old. A decreased risk of LRR with PMRT vs. no PMRT (HR = 0.304, 95% CI: 0.204-0.454) was maintained in all ages. The HR of PMRT vs. no PMRT for DFS and OS gradually increased with age. In patients ≤50 years old, PMRT was independently associated with favorable LRR, DFS, and OS, all P < 0.05). In patients >50 years old, PMRT was independently associated with reduced LRR (P = 0.004), but had no effect on DFS or OS.

CONCLUSIONS

Age was an independent prognostic factor for pT1-2N1 breast cancer; PMRT provided survival benefits for patients ≤50 years old, but not for patients >50 years old.

Impact of Molecular Profiling of Breast Cancer on the Rate of Locoregional Recurrence in Young Versus Old Female Patients

Background

Breast cancer (BC) is diverse regarding its natural history and treatment responses. The traditional histopathological classification is unable to confine this diverse clinical heterogeneity. Classically, prognosis and treatment response are influenced by factors including histological grade, lymph node status, and tumour size. Recently, research has diverted from histological classification towards molecular classification.

We aim to analyse the locoregional recurrence of breast cancer incidence following surgery across the different molecular subtypes as well as relation to age.

Materials and methods

Female patients diagnosed with a locoregional recurrence of breast carcinoma in 2012-2014 were identified from our centre histology department. We only included stage I-III patients who were previously treated with surgery achieving negative surgical margins and later developed locoregional recurrence during our study period. These patients were subdivided by age into old (≥40 years old) and young (<40 years old) groups according to their initial diagnosis age. Furthermore, they were categorised according to the molecular subtype of their primary tumour.

Results

Our study included 184 patients (124 designated to the old age group, 60 to the young age group). In the young group, recurrence occurred after a mean of 4.3 years and the range was one to 23 years, while in the old group, the mean was 3.8 years, and the range was one to 14 years. The most primary cancer subtype recorded was triple-negative (41.85%): 50 old patients and 27 young. Next was the Her-2/neu enriched subtype (27.72%): 35 old patients and 16 young, following this was luminal A subtype (21.19%): 27 old and 12 young. Last was the luminal B subtype (9.24%): 12 old patients and five young.

Conclusions

To conclude, in our series, the most common molecular subtype found in the recurrent cases was the luminal negative subtypes, with a relatively similar pattern across both age groups. The results of this study can be used as a basis for large prospective studies in our centre to further analyse the effect of molecular subtyping on the recurrence rates of BC.

Breast cancer by migrant background in Belgium: Lower risk, but worse survival in women of non-European origin

Foreign and native populations differ in terms of breast cancer outcomes. Studies rarely distinguish between premenopausal and postmenopausal breast cancer, although the risk profile is different; nor between migrants of the first and second generation (FG and SG), which is crucial to examine genetic and environmental influences on breast cancer. This research fills these gaps by investigating patterns in breast cancer incidence and survival in different migrant groups by menopausal and migrant generational status, taking various risk factors into account. To this end, individually linked data from the 2001 census, the Belgian Cancer Registry and the Crossroads Bank for Social Security are used. Age-standardised incidence rates and incidence rate ratios are calculated by migrant background group, stratified according to ages 30-50 (premenopausal) and 50-70 (postmenopausal). Incidence rate ratios are examined with and without taking reproductive factors and socioeconomic position (SEP) into account. Relative survival percentages and relative excess risks of dying among premenopausal and postmenopausal patients are computed with and without controlling for the stage at diagnosis and SEP. Premenopausal breast cancer is further examined by migrant generational status. Breast cancer incidence is lower among non-European migrants compared to Belgians. Keeping SEP and known risk factors constant reduces much, but not all of the observed discrepancies. A risk convergence between SG migrants and Belgians for the development of premenopausal breast cancer is observed. Premenopausal breast cancer survival is worse among Moroccan patients due to a higher stage at diagnosis. This disadvantage is concentrated in the FG.

Precision Medicine and Radiogenomics in Breast Cancer: New Approaches toward Diagnosis and Treatment

Precision medicine is medicine optimized to the genotypic and phenotypic characteristics of an individual and, when present, his or her disease. It has a host of targets, including genes and their transcripts, proteins, and metabolites. Studying precision medicine involves a systems biology approach that integrates mathematical modeling and biology genomics, transcriptomics, proteomics, and metabolomics. Moreover, precision medicine must consider not only the relatively static genetic codes of individuals, but also the dynamic and heterogeneous genetic codes of cancers. Thus, precision medicine relies not only on discovering identifiable targets for treatment and surveillance modification, but also on reliable, noninvasive methods of identifying changes in these targets over time. Imaging via radiomics and radiogenomics is poised for a central role. Radiomics, which extracts large volumes of quantitative data from digital images and amalgamates these together with clinical and patient data into searchable shared databases, potentiates radiogenomics, which is the combination of genetic and radiomic data. Radiogenomics may provide voxel-by-voxel genetic information for a complete, heterogeneous tumor or, in the setting of metastatic disease, set of tumors and thereby guide tailored therapy. Radiogenomics may also quantify lesion characteristics, to better differentiate between benign and malignant entities, and patient characteristics, to better stratify patients according to risk for disease, thereby allowing for more precise imaging and screening. This report provides an overview of precision medicine and discusses radiogenomics specifically in breast cancer. ^© RSNA, 2018.

Genetic and environmental factors and serum hormones, and risk of estrogen receptor-positive breast cancer in pre- and postmenopausal Japanese women

Breast cancer incidence in Japanese women has more than tripled over the past two decades. We have previously shown that this marked increase is mostly due to an increase in the estrogen receptor (ER)-positive, HER2-negative subtype. We conducted a case-control study; ER-positive, HER2-negative breast cancer patients who were diagnosed since 2011 and women without disease were recruited. Environmental factors, serum levels of testosterone and 25-hydroxyvitamin D, and common genetic variants reported as predictors of ER-positive breast cancer or found in Asian women were evaluated between patients and controls in pre- and postmenopausal women. To identify important risk predictors, risk prediction models were created by logistic regression models. In premenopausal women, two environmental factors (history of breastfeeding, and history of benign breast disease) and four genetic variants (TOX3-rs3803662, ESR1-rs2046210, 8q24-rs13281615, and SLC4A7-rs4973768) were considered to be risk predictors, whereas three environmental factors (body mass index, history of breastfeeding, and hyperlipidemia), serum levels of testosterone and 25-hydroxyvitamin D, and two genetic variants (TOX3-rs3803662 and ESR1-rs2046210) were identified as risk predictors. Inclusion of common genetic variants and serum hormone measurements as well as environmental factors improved risk assessment models. The decline in the birthrate according to recent changes of lifestyle might be the main cause of the recent notable increase in the incidence of ER-positive breast cancer in Japanese women.

Do Breast Cancer Risk Factors Affect the Survival of Breast Cancer Patients in Southern Sri Lanka?

Background:

Breast cancer continues to be a major cause of morbidity among women in Sri Lanka. Possible effects of etiological risk factors on breast cancer specific survival (BCSS) of the disease is not clear. This study was designed to explore the impact of breast cancer risk factors on the BCSS of patients in Southern Sri Lanka.

Method:

This retro-prospective study included all breast cancer patients who had sought immunohistochemistry services at our unit from May 2006 to December 2012. A pre-tested, interviewer-administered questionnaire was used to gather information on risk factors. BCSS was estimated using the Kaplan-Meier model. Univariate Cox-regression analysis was performed with 95% confidence intervals using the SPSS statistical package.

Results:

A total of 944 breast cancer patients were included. Five year BCSS was 78.8%. There was a statistically significant difference between the patients who had a family history of breast cancer and no family history of any cancer in terms of the presence/absence of lymph node metastasis (p=0.011) and pathological stage (p=0.042). The majority of the premenopausal patients had associated DCIS (p<0.001) and large tumours (p=0.015) with positive lymph nodes (p=0.016). There was no statistically significant association between hormone receptor subtypes and hormone related risk factors. Univariate analysis revealed that breast cancer risk factors had no significant effect on the BCSS.

Conclusion:

Even though family history of breast cancer and premenopausal status are associated with poor prognostic features, they, in line with the other breast cancer risk factors, appear to have no significant effect on the BCSS of patients in Southern Sri Lanka.

How could breast cancer molecular features contribute to locoregional treatment decision making?

Systemic treatments are tailored to breast cancer (BC) heterogeneity, which is not yet taken into account for radiotherapy (RT) personalization. The primary objective of this review is to summarize existing data suggesting BC subtypes and genetic assays are prognostic and predictive biomarkers useful for RT decision-making and to provide implications for their incorporation into future translational and clinical research. The evidence suggesting that BC subtypes also exhibit distinct "locoregional recurrence (LRR)" patterns is retrospective but consistent and validated in over fifteen studies. The HER-2 positive and triple negative subtypes are the most susceptible to locoregional failure. The high risk of the HER-2 positive subtype can be reversed with trastuzumab administration. Very little is known on the subtypes' intrinsic radiosensitivity properties. Genetic assays have assessed retrospectively signatures' prognostic and predictive value in patients' cohorts (several coming from prospective studies) for LRR risk and radiotherapy (RT) benefit. Further confirmation is needed before their introduction into clinical routine. Evidence on the use of molecular biomarkers for adjuvant RT tailoring is emerging but needs validation and introduction into prospective studies. The plethora of modern RT options (partial breast irradiation, hypofractionation), as well as recent evidence pointing towards more extensive radiotherapy, demand introduction of biological features into clinical trials to improve therapeutic decisions. Open questions, such as tailoring of irradiation after neo-adjuvant chemotherapy in complete responders and the understanding of the interplay between local control, systemic recurrence and survival given modern systemic treatments, need to be addressed under the prism of biology within this heterogeneous disease. Intrinsic radiobiological properties within this heterogeneity need to be highlighted in order to further improve outcomes.

The clinical prognostic value of molecular intrinsic tumor subtypes in older breast cancer patients: A FOCUS study analysis

INTRODUCTION

It was recently proposed that the molecular breast tumor subtypes are differently distributed in the elderly breast cancer patients, and also lack prognostic value. Given the limited number of elderly patients in previous studies, the aim of this study was to determine the prognostic effect of the molecular intrinsic subtypes in a large older breast cancer population.

MATERIAL AND METHOD

Older breast cancer patients with invasive, non-metastatic breast cancer with tumor material available for immunohistochemical determination of Ki67, EGFR, CK5/6 and HER-2 were included. ER and PR expression was retrieved from the pathology report. Molecular subtypes were: Luminal A, Luminal B, ERBB2, Basal-like and Unclassified. Primary endpoint was Relapse Free Period (RFP), taking into account the competing risk of mortality, and adjusted for the most important patient, tumor and treatment characteristics. Secondary endpoint was Relative Survival (RS).

RESULTS

Overall, 1362 patients were included. Patients with a Luminal A subtype had the lowest risk of recurrence (11% at 5 yrs). Patients with a Basal (24% at 5yrs) or ERBB2 (34% at 5yrs) molecular breast tumor subtype had the highest risk of recurrence. The ERBB2 subtype had the worst prognosis in terms of RFP (SHR 2.07, 95% CI 1.35-3.20; p = 0.001). The worst RS was again observed for the ERBB2 subtype (48% at 10 yrs). In multivariable analyses, the relative excess risk of death for all molecular subtypes was significantly worse compared to the Luminal A subtype.

CONCLUSION

Molecular intrinsic breast tumor subtypes have significant prognostic value in the elderly population, even after taking competing mortality into account.

Clinicopathological factors predicting early and late distant recurrence in estrogen receptor-positive, HER2-negative breast cancer

BACKGROUND

Most studies analyzing prognostic factors for late relapse have been performed in postmenopausal women who received tamoxifen or aromatase inhibitors as adjuvant endocrine therapy for estrogen receptor (ER)-positive breast cancer.

METHODS

A total of 223 patients (108 premenopausal and 115 postmenopausal) with early distant recurrence and 149 patients (62 premenopausal and 87 postmenopausal) with late distant recurrence of ER-positive, HER2-negative breast cancer who were given their initial treatment between 2000 and 2004 were registered from nine institutions. For each late recurrence patient, approximately two matched control patients without relapse for more than 10 years were selected. Clinicopathological factors and adjuvant therapies were compared among the three groups by menopausal status and age.

RESULTS

Factors predicting early recurrence in premenopausal women were large tumor size, high lymph node category and high tumor grade, whereas predictors for late recurrence were large tumor size and high lymph node category. In postmenopausal women under 60 years of age, factors predicting early recurrence were bilateral breast cancer, large tumor size, high lymph node category, low PgR expression and high Ki67 labeling index (LI), while predictors for late recurrence were large tumor size and high lymph node category. On the other hand, in postmenopausal women aged 60 years or older, factors predicting early recurrence were bilateral breast cancer, large tumor size, high lymph node category, high tumor grade, low ER expression and high Ki67 LI, whereas predictors for late recurrence were high lymph node category, low ER expression and short duration of adjuvant endocrine therapy.

CONCLUSION

Predictors of early and late distant recurrence might differ according to menopausal status and age.

The characteristics of breast cancer subtypes: implications for treatment guidelines and individualized treatment strategies in China

This study aimed at investigating the characteristics of invasive breast cancer among molecular subtypes. Patients with invasive breast cancer, with complete information on the expressions of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor-2 (HER2), were recruited. χ tests and an unconditional logistic regression model were used for statistical analysis. The percentages of luminal A, luminal B, HER2/neu, and triple-negative subtypes were 54.2% (1639/3021), 14.0% (422/3021), 8.9% (269/3021), and 22.9% (691/3021), respectively. Differences among molecular subtypes (P<0.05) in tumor size, stage, pathologic type, and lymph node status were observed. The HER2/neu, luminal B, and triple-negative subtypes were more aggressive compared with the luminal A subtype in tumor stage, lymph node status, or pathologic type (P<0.05), when the findings were adjusted for age. Molecular subtypes were distributed differently between both age groups and regional groups on the basis of the socioeconomic status (P<0.05). In conclusion, luminal A and triple-negative subtypes were the 2 main subtypes of invasive breast cancer in China. The variations of molecular subtypes in pathology, age, and regional distribution may give some suggestions for updating treatment guidelines and individualized treatment strategies in China.

Association of TGF-β2 levels in breast milk with severity of breast biopsy diagnosis

PURPOSE

TGF-β plays a dual role in breast carcinogenesis, acting at early stages as tumor-suppressors and later as tumor-promoters. TGF-β isoforms are expressed in breast tissues and secreted in milk, suggesting that analysis of levels in milk might be informative for breast cancer risk. Accordingly, we assessed TGF-β2 levels in milk from women who had undergone a breast biopsy and related the concentrations to diagnosis.

METHODS

Milk donated by women who had undergone or were scheduled for a breast biopsy was shipped on ice for processing and testing. Breast cancer risk factors were obtained through a self-administered questionnaire, and biopsy diagnoses were extracted from pathology reports. TGF-β2 levels in milk, assessed as absolute levels and in relation to total protein, were analyzed in bilateral samples donated by 182 women. Linear regression was used to estimate relationships of log-transformed TGF-β2 levels and TGF-β2/ total protein ratios to biopsy category.

RESULTS

Milk TGF-β2 levels from biopsied and non-biopsied breasts within women were highly correlated (r (2) = 0.77). Higher mean TGF-β2 milk levels (based on average of bilateral samples) were marginally associated with more severe breast pathological diagnosis, after adjusting for duration of nursing current child (adjusted p trend = 0.07).

CONCLUSIONS

Our exploratory analysis suggests a borderline significant association between higher mean TGF-β2 levels in breast milk and more severe pathologic diagnoses. Further analysis of TGF-β signaling in milk may increase understanding of postpartum remodeling and advance efforts to analyze milk as a means of assessing risk of breast pathology.

How many etiological subtypes of breast cancer: two, three, four, or more?

Breast cancer is a heterogeneous disease, divisible into a variable number of clinical subtypes. A fundamental question is how many etiological classes underlie the clinical spectrum of breast cancer? An etiological subtype reflects a grouping with a common set of causes, whereas a clinical subtype represents a grouping with similar prognosis and/or prediction. Herein, we review the evidence for breast cancer etiological heterogeneity. We then evaluate the etiological evidence with mRNA profiling data. A bimodal age distribution at diagnosis with peak frequencies near ages 50 and 70 years is a fundamental characteristic of breast cancer for important tumor features, clinical characteristics, risk factor profiles, and molecular subtypes. The bimodal peak frequencies at diagnosis divide breast cancer overall into a "mixture" of two main components in varying proportions in different cancer populations. The first breast cancer tends to arise early in life with modal age-at-diagnosis near 50 years and generally behaves aggressively. The second breast cancer occurs later in life with modal age near 70 years and usually portends a more indolent clinical course. These epidemiological and molecular data are consistent with a two-component mixture model and compatible with a hierarchal view of breast cancers arising from two main cell types of origin. Notwithstanding the potential added value of more detailed categorizations for personalized breast cancer treatment, we suggest that the development of better criteria to identify the two proposed etiologic classes would advance breast cancer research and prevention.

MicroRNA profile in very young women with breast cancer

Background

Breast cancer is rarely diagnosed in very young women (35years old or younger), and it often presents with distinct clinical-pathological features related to a more aggressive phenotype and worse prognosis when diagnosed at this early age. A pending question is whether breast cancer in very young women arises from the deregulation of different underlying mechanisms, something that will make this disease an entity differentiated from breast cancer diagnosed in older patients.

Methods

We performed a comprehensive study of miRNA expression using miRNA Affymetrix2.0 array on paraffin-embedded tumour tissue of 42 breast cancer patients 35 years old or younger, 17 patients between 45 and 65 years old and 29 older than 65 years. Data were statistically analyzed by t-test and a hierarchical clustering via average linkage method was conducted. Results were validated by qRT-PCR. Putative targeted pathways were obtained using DIANA miRPath online software.

Results

The results show a differential and unique miRNA expression profile of 121 miRNAs (p-value <0.05), 96 of those with a FDR-value <0.05. Hierarchical clustering grouped the samples according to their age, but not by subtype nor by tumour characteristics. We were able to validate by qRT-PCR differences in the expression of 6 miRNAs: miR-1228*, miR-3196, miR-1275, miR-92b, miR-139 and miR-1207. Moreover, all of the miRNAs maintained the expression trend. The validated miRNAs pointed out pathways related to cell motility, invasion and proliferation.

Conclusions

The study suggests that breast cancer in very young women appears as a distinct molecular signature. To our knowledge, this is the first time that a validated microRNA profile, distinctive to breast cancer in very young women, has been presented. The miRNA signature may be relevant to open an important field of research in order to elucidate the underlying mechanism in this particular disease, which in a more clinical setting, could potentially help to identify therapeutic targets in this particular set of patients.

Association between oestrogens receptor expressions in breast cancer and comorbidities: a cross-sectional, population-based study

Background

Breast cancer with oestrogen receptor expression is common in older women. Several factors, such as age and reproductive hormone exposure, have been associated with oestrogen receptor expression in breast cancer. However, the association between comorbidities and the oestrogen receptor expression has been poorly studied. We hypothesized that there was an association between burden comorbidity and breast cancer with oestrogen receptor expression in older women.

Objective

To determine whether oestrogen receptor expression in breast cancer was associated with burden comorbidity in community-dwelling women.

Methods

A total of 1,707 women with breast cancer registered on the list of a breast cancer registry were included. The recorded data included: age, Charlson Comorbidity Index score≥1, breast cancer characteristics (coded according to the International Classification of Diseases for Oncology), and breast cancer pathological stage (the pathological-tumour-node-metastasis, Scarff Bloom Richardson, and hormonal status of oestrogen receptor, progesterone receptor, and human epidermal growth factor receptor).

Results

Breast cancer with oestrogen receptor expression was identified in 1,378 patients (80·7%). The fully-adjusted logistic regression showed that oestrogen receptor expression was associated with Charlson Comorbidity Index score≥1 (odds ratio [OR] = 1·91,95%confidence interval [CI] = [1.01–3.61], P = 0·048), progesterone receptor expression (OR = 16·64, 95%CI = [11.62–23.81], P<0·001), human epidermal growth factor receptor (OR = 0·54, 95%CI = [0.34–0.84], P = 0·007), age (OR = 1.02, 95%CI = [1.00–1.03], P = 0.008), Scarff Bloom Richardson grade II and grade III (OR = 0·21with 95%CI = [0.10–0.44] and OR = 0·06 with 95%CI = [0.03–0.12], P<0·001).

Conclusion

Our findings provide new data showing an independent positive association between burden comorbidity and breast cancer with oestrogen receptor expression. This result confirms that evaluation of oestrogen receptor expression in breast cancer should not be limited to hormonal factors stratified by age.

Comparison of frequencies and prognostic effect of molecular subtypes between young and elderly breast cancer patients

PURPOSE

To compare the distribution and prognostic effect of the breast cancer molecular subtypes in young and elderly breast cancer patients.

PATIENTS AND METHODS

Our study population (n = 822) consisted of all early breast cancer patients primarily treated with surgery in our center between 1985 and 1996. A total of 142/822 fresh frozen tissues were available with good quality RNA and analyzed by gene expression microarray. Gene expression molecular subtypes were determined by correlation to the expression centroids of 534 "intrinsic" genes. Sections of a tissue micro array containing formalin-fixed paraffin-embedded tumor tissue of 714/822 patients were immunohistochemically (IHC) stained for Ki67, EGFR, CK5/6. Tumor expression of ER, PR, HER2 was previously determined. IHC molecular subtypes were defined based on expression of these markers: Luminal A: ER+ and/or PR+, HER2- and Ki67-; Luminal B: ER+ and/or PR+ and ki67+; ERBB2: ER-, PR- and HER2+; Basal-like: ER-, PR-, HER2- and EGFR+ and/or CK5/6+; Unclassified: ER-, PR-, HER2-, EGFR- and CK5/6-. IHC molecular subtypes were validated against gene expression defined molecular subtypes. Assessment of distribution and prognostic effect of molecular subtypes was stratified to age (<65 versus ≥65 years).

RESULTS

Validation of molecular subtypes determined by IHC against gene expression revealed a substantial agreement in classification (Cohen's kappa coefficient 0.75). A statistically significant association (p = 0.02) was found between molecular subtypes and age, where Luminal tumors were more often found in elderly patients, while ERBB2, basal-like and unclassified subtypes were more often found in young patients. Molecular subtypes showed a prognostic association with outcome in young patients concerning relapse-free period (RFP) (p = 0.01) and relative survival (RS) (p < 0.001). No statistically significant prognostic effect was found for molecular subtypes in elderly patients (RFP p = 0.5; RS p = 0.1). Additional analyses showed that no molecular subtypes showed a statistically significant difference in outcome for elderly compare to young patients.

CONCLUSION

We have shown that molecular subtypes have a different distribution and prognostic effect in elderly compared to young breast cancer patients, emphasizing the fact that biomarkers may have different distributions and prognostic effects and therefore different implications in elderly compared to their younger counterparts. Our results support the premise that breast cancer clinical behavior is significantly affected by patient age. We suggest that competing risks of death in elderly patients, ER-driven differences and micro-environmental changes in biology are underlying these age-dependent variations in patient prognosis.

The effect of local therapy on breast cancer mortality: is there an age-interaction?

There are no randomized trials comparing local therapy versus no therapy in patients with primary breast cancer, as such trials would be deemed unethical. Thus, the impact of local therapy on breast cancer mortality is poorly understood. However, an overview of clinical trials comparing various permutations in the local therapy of breast cancer suggests that inadequate local therapy increases the risk of local recurrences, and thereby increases breast cancer mortality. Yet, age-interactions are commonly reported in studies that have examined the etiology, prognosis, and treatment of breast cancer, and might be associated with the effect of local therapy as well. Moreover, the effect of local therapy on breast cancer mortality might be time-dependent. In cohorts of women with high-risk tumors (predominantly younger women) local therapy may adversely (but only transiently) perturb the natural history of breast cancer. In contrast, such an effect is not evident in cohorts of women with low-risk tumors (predominantly older women). For both groups of patients, local therapy appears to ultimately have a beneficial effect in reducing breast cancer mortality, but in patients with low-risk tumors the benefit is immediate, while in patients with high-risk tumors it is delayed. Evidence for such an age-interaction is derived from comparison of the breast cancer hazard curves in women with high-risk and low-risk tumors, and analysis of the mammography screening trials. Neo-adjuvant systemic therapy may eventually prove useful in modulating the effects of local therapy.

Divergent estrogen receptor-positive and -negative breast cancer trends and etiologic heterogeneity in Denmark

Long-term breast cancer trends in incidence in the United States (US) show rising estrogen receptor (ER)-positive rates and falling ER-negative rates. We hypothesized that these divergent trends reflect etiologic heterogeneity and that comparable trends should be observed in other countries with similar risk factor profiles. Therefore, we analyzed invasive female breast cancers in Denmark, a country with similar risk factors as the US. We summarized the overall trend in age-standardized rates with the estimated annual percentage change (EAPC) statistic (1993-2010) and used age-period-cohort models to estimate age-specific EAPCs, cohort rate ratios and projections for future time periods (2011-2018). In Denmark, the overall rate of ER-positive cancers rose between 1993 and 2010 by 3.0% per year (95% CI: 2.8-3.3% per year), whereas the overall rate of ER-negative cancers fell by 2.1% per year (95% CI: -2.5 to -1.6% per year). The ER-positive rate increased fastest among postmenopausal women and the ER-negative rate decreased fastest among premenopausal women, reflecting that cohorts born after 1944 were at relatively higher risk of ER-positive tumors and lower risk of ER-negative tumors. If current trends continue, ER-positive cancers will increase at least 13% by 2018 in Denmark, ER-negative cancers will fall 15% by 2018, and breast cancer overall will increase at least 7% by 2018. Divergent ER-specific trends are consistent with distinct etiologic pathways. If trends in known risk factors are responsible, the Danish and US experience may foreshadow a common pattern worldwide.

Postpartum remodeling, lactation, and breast cancer risk: summary of a National Cancer Institute-sponsored workshop

The pregnancy-lactation cycle (PLC) is a period in which the breast is transformed from a less-developed, nonfunctional organ into a mature, milk-producing gland that has evolved to meet the nutritional, developmental, and immune protection needs of the newborn. Cessation of lactation initiates a process whereby the breast reverts to a resting state until the next pregnancy. Changes during this period permanently alter the morphology and molecular characteristics of the breast (molecular histology) and produce important, yet poorly understood, effects on breast cancer risk. To provide a state-of-the-science summary of this topic, the National Cancer Institute invited a multidisciplinary group of experts to participate in a workshop in Rockville, Maryland, on March 2, 2012. Topics discussed included: 1) the epidemiology of the PLC in relation to breast cancer risk, 2) breast milk as a biospecimen for molecular epidemiological and translational research, and 3) use of animal models to gain mechanistic insights into the effects of the PLC on breast carcinogenesis. This report summarizes conclusions of the workshop, proposes avenues for future research on the PLC and its relationship with breast cancer risk, and identifies opportunities to translate this knowledge to improve breast cancer outcomes.

Clinico-pathological features of breast carcinoma in elderly Egyptian patients: a comparison with the non-elderly using population-based data

BACKGROUND

Breast cancer (BC) is a major worldwide health care problem that mostly afflicts the elderly population in the more developed countries. It is not known how common is breast cancer among elderly Egyptian patients and whether this differs from the disease in younger patients.

AIMS

To study the clinico-pathological features of BC in elderly Egyptian patients (⩾65years of age) among the population of an Egyptian Governorate, Gharbiah, and to compare these features with those of younger patients (<65years).

METHODS

This is a cross sectional study that compares elderly BC (EBC) and the non-elderly BC (NEBC) using the information from the Gharbiah Population-based Cancer registry (GPCR) during the years 1999-2007.

RESULTS

Out of 6078 BCs, 12% were EBCs and 88% were NEBCs. Between 1999 and 2007, the crude incidence rate (CIR, per 100,000 populations) of EBC increased from 47 to 71 and that of NEBC increased from 16 to 17. Compared to NEBC patients, EBC patients were more likely to have a positive family history and present with a distant disease and less likely to present with a localized disease. EBCs were more likely to have lung metastases and less likely to have liver metastases. Histology, grade, hormone and HER-2 receptor statuses were comparable in both groups. Apart from hormonal therapies, the elderly were less likely to receive surgery, radiotherapy or chemotherapy.

CONCLUSION

EBC patients in Egypt present with advanced disease and are less likely to receive surgery, radiotherapy or chemotherapy compared to NEBC patients.

Age Interactions in Breast Cancer: An Analysis of a 10-Year Multicentre Study in China

OBJECTIVES: The effects of age at diagnosis on the clinical characteristics of breast cancer and trends over time were investigated in Chinese women. METHODS: Data from 4211 women with pathologically confirmed primary breast cancer collected between 1999 and 2008 for a multicentre retrospective study were analysed according to age at diagnosis. RESULTS: Age at diagnosis ranged from 21 to 86 years, with a mean of 48.7 years, and was shown to be significantly related to tumour size, lymph node status, hormone receptor status and human growth factor receptor-2 status, but not to pathological type or tumour, node, metastasis stage. The age-corrected proportion of patients aged 50 – 64 years at diagnosis increased significantly between 1999 and 2008. There was a significant difference in the age-corrected distribution of age at diagnosis in China compared with Western countries. CONCLUSIONS: Age at diagnosis is related to the clinical and pathological characteristics of breast cancer. The age at diagnosis in China increased over the decade from 1999 to 2008, but is still lower than in Western countries.

Association of time since last birth, age at first birth and parity with breast cancer survival among parous women: a register-based study from Norway

Reproductive factors that have a well-documented effect on breast cancer risk may also influence the prognosis of the disease, but previous studies on breast cancer survival have yielded conflicting results. We combined information from two population-based registries and obtained information on 16,970 parous women with invasive breast cancer. Cox regression analysis was used to assess breast cancer survival in relation to age at diagnosis, age at first birth, time since last birth and parity. We stratified the analyses by age at diagnosis (<50 and ≥ 50 years) as an approximation for menopausal age. In women diagnosed before 50 years of age, breast cancer survival was reduced with younger age at diagnosis (p for trend <0.001), whereas in women diagnosed at 50 years or later, survival was reduced with older age at diagnosis (p for trend 0.011). For breast cancer diagnosed before 50 years, survival was poorer in women with four or more births compared to women with one or two births (hazard ratio 1.3, 95% confidence interval 1.1-1.6). A short time since last birth was associated with reduced survival (p for trend 0.05), but adjustment for stage and grade attenuated the association. Among women diagnosed at 50 years or later, we found no association with survival for any of the reproductive factors. In summary, reproductive factors were associated with survival from breast cancer diagnosed before but not after age 50 years. Young women had a particularly poor prognosis throughout the study period.

Occurrence of breast cancer subtypes in adolescent and young adult women

Introduction

Breast cancers are increasingly recognized as heterogeneous based on expression of receptors for estrogen (ER), progesterone (PR), and human epidermal growth factor receptor 2 (HER2). Triple-negative tumors (ER^-/PR^-/HER2^-) have been reported to be more common among younger women, but occurrence of the spectrum of breast cancer subtypes in adolescent and young adult (AYA) women aged between 15 and 39 years is otherwise poorly understood.

Methods

Data regarding all 5,605 AYA breast cancers diagnosed in California during the period 2005 to 2009, including ER and PR status (referred to jointly as hormone receptor (HR) status) and HER2 status, was obtained from the population-based California Cancer Registry. Incidence rates were calculated by subtype (triple-negative; HR⁺/HER2^-; HR⁺/HER2⁺; HR^-/HER2⁺), and logistic regression was used to evaluate differences in subtype characteristics by age group.

Results

AYAs had higher proportions of HR⁺/HER2⁺, triple-negative and HR^-/HER2⁺ breast cancer subtypes and higher proportions of patients of non-White race/ethnicity than did older women. AYAs also were more likely to be diagnosed with stage III/IV disease and high-grade tumors than were older women. Rates of HR⁺/HER2^- and triple-negative subtypes in AYAs varied substantially by race/ethnicity.

Conclusions

The distribution of breast cancer subtypes among AYAs varies from that observed in older women, and varies further by race/ethnicity. Observed subtype distributions may explain the poorer breast cancer survival previously observed among AYAs.

Epidemiology of triple negative breast cancers

Triple negative (TN) breast cancers fail to express the three most common breast cancer receptors; i.e., estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2). Accumulating data demonstrate that epidemiological risk factor profiles also vary between TN (ER-PR-HER2-) and other breast cancers, especially the so-called Luminal A breast cancers (ER+PR ± HER2-) [1]. A more comprehensive understanding of the epidemiology of TN breast cancers has important public health implications for risk assessment [2], prevention and treatment. The epidemiology of TN breast cancers can be first understood in the age-related reproductive risk factor patterns for ER, PR, and HER2. For example, there is a clear and strong association between older age at diagnosis (and therefore postmenopausal status) and the development of ER positive, PR positive, and HER2 negative breast cancers. On the other hand, younger age at diagnosis (and premenopausal status) is related to the development of ER negative, PR negative, and HER2 positive breast cancers. This gives rise to the somewhat counterintuitive suggestion that menopause has a greater relative impact upon hormone receptor negative than positive breast cancers [3,4]. Throughout this review, we will primarily contrast ER-PR-HER2- (TN) with ER+PR ± HER2- (Luminal A) breast cancers. We will first summarize the population-based age-specific incidence rate patterns and clinical outcomes, and then will review the available analytical studies. Information sources for this review included the National Cancer Institute's Surveillance, Epidemiology, and End Results 13 Registries Public-Use Database [5], CANCERLIT, Index Medicus, and PubMed.

Age determines the prognostic role of the cancer stem cell marker aldehyde dehydrogenase-1 in breast cancer

Background

The purpose of this study was to compare the expression and the prognostic effect of the breast cancer stem cell marker aldehyde dehydrogenase-1 (ALDH1) in young and elderly breast cancer patients.

Methods

The study population (N = 574) consisted of all early breast cancer patients primarily treated with surgery in our center between 1985 and 1994. Median follow-up was 17.9 years (range: 0.1 to 23.5). Tissue microarray slides were immunohistochemically stained for ALDH1 expression and quantified by two independent observers who were blinded to clinical outcome. Assessment of the prognostic effect of ALDH1 expression was stratified according to age and systemic treatment.

Results

Complete lack of expression of ALDH1 was found in 40% of tumors. With increasing age more tumors showed complete absence of ALDH1 expression (P < .001). In patients aged > 65 years, ALDH1 status was not associated with any clinical outcome. Conversely, in patients aged < 65 years, ALDH1 positivity was an independent risk factor of worse outcome for relapse free period (hazard ratio = 1.71 (95% CI, 1.09 to 2.68); P = .021) and relative survival (relative excess risks of death = 2.36 (95% CI, 1.22 to 3.68); P = .016). Ten-year relative survival risk was 57% in ALDH1-positive patients compared to 83% in ALDH1-negative patients.

Conclusion

ALDH1 expression and its prognostic effect are age-dependent. Our results support the hypothesis that breast cancer biology is different in elderly patients compared to their younger counterparts and emphasizes the importance of taking into consideration age-specific interactions in breast cancer research.

Global breast cancer: the lessons to bring home

Breast cancer is the most common cancer affecting women globally. This paper discusses the current progress in breast cancer in Western countries and focuses on important differences of this disease in low- and middle-income countries (LMCs). It introduces several arguments for applying caution before globalizing some of the US-adopted practices in the screening and management of the disease. Finally, it suggests that studies of breast cancer in LMCs might offer important insights for a more effective management of the problem both in developing as well as developed countries.

Breast cancers in U.S. residing Indian-Pakistani versus non-Hispanic White women: comparative analysis of clinical-pathologic features, treatment, and survival

South Asians from India and Pakistan represent one of the fastest growing immigrant populations in the US, yet there are limited data assessing breast cancers for this distinct ethnic sub-group. The aim of this study was to analyze clinical-pathologic, treatment and outcome characteristics of U.S.-residing Indian-Pakistani (IP) versus non-Hispanic white (NHW) female breast cancer patients to assess if any differences/disparities exist. The study cohort consisted of 2,393 IP and 555,832 NHW women (diagnosed 1988-2006) in the SEER database. Differences between the two populations were analyzed using chi-squared and multivariate regression analysis. Age-adjusted incidence, mortality, and relative survival rates were calculated for the two groups. Significant differences in the characteristics of the IP cohort's invasive disease included: younger median age at presentation; larger tumor size; higher stage, higher grade, more involved lymph-nodes, and more hormone receptor negative disease (all P < 0.01). The age-adjusted incidence and breast cancer mortality were lower in IP women. The relative survival at 5 years was statistically significant at 84% for IP versus 89% for NHW women, but was not significantly different on multivariate analysis (P > 0.05). Within each stage (Tis, I, II), there were no disparities in the rate of breast conservation surgery (BCS) or in the percentage of patients receiving adjuvant radiation after BCS for the 2 cohorts. Post-mastectomy radiation was delivered significantly more often in stage I/II IP patients undergoing mastectomy. In conclusion, this analysis suggests that while there appear to be significant differences in the features of breast cancers of US-residing IP women, no disparities were noted in the rates of breast conserving surgery or adjuvant radiation, as seen in some other ethnicities. The more aggressive clinical-pathologic features stage-for-stage in IP women may partially explain the more frequent use of post-mastectomy RT in this patient population. These findings warrant further investigation.

Qualitative age interactions in breast cancer studies: a mini-review

A qualitative age interaction is defined as the reversal of relative risks or rates according to age at onset, and is often evident in studies that examine the etiology, prognosis and treatment of breast cancer. For example, incidence rates (or risks) are higher for aggressive when compared with indolent breast cancers prior to age 40-50 years, after which rates are higher for indolent tumors. Nulliparity and obesity decrease breast cancer risk in younger women, but increase risk in older women. Curves depicting the annual hazard of breast cancer death are shaped differently for the early- and late-onset tumors. Clinical trials for mammography screening, fenretinide chemoprevention and neo-adjuvant chemotherapy show opposite effects in younger and older women. Finally, high-risk/early onset breast cancers are more common among African-American women than Caucasian women, and this may partly account for the racial survival disparities. Taken together, these examples imply that aging may modify breast cancer risk, prognosis and treatment. These qualitative age interactions (or effect modifications) are important because they suggest that high-risk/early-onset and low-risk/late-onset breast cancers are different diseases, derived from different carcinogenic pathways. When age interactions are suspected, breast cancer studies should be stratified by early versus late age of onset or analyzed age specifically.

Declining incidence of contralateral breast cancer in the United States from 1975 to 2006

PURPOSE

Contralateral breast cancer (CBC) is the most frequent new malignancy among women diagnosed with a first breast cancer. Although temporal trends for first breast cancers have been well studied, trends for CBC are not so well established.

PATIENTS AND METHODS

We examined temporal trends in CBC incidence using US Surveillance, Epidemiology, and End Results database (1975 to 2006). Data were stratified by estrogen receptor (ER) status of the first breast cancer for the available time period (1990+). We estimated the annual percent change (EAPC) in CBC rates using Poisson regression models adjusted for the age at and time since first breast cancer diagnosis.

RESULTS

Before 1985, CBC incidence rates were stable (EAPC, 0.27% per year; 95% CI, -0.4 to 0.9), after which they declined with an EAPC of -3.07% per year (95% CI, -3.5 to -2.7). From 1990 forward, the declines were restricted to CBC after an ER-positive cancer (EAPC, -3.18%; 95% CI, -4.2 to -2.2) with no clear decreases after an ER-negative cancer. Estimated current age-specific CBC rates (per 100/year) after an ER-positive first cancer were: 0.45 for first cancers diagnosed before age 30 years and 0.25 to 0.37 for age 30 years or older. Rates after an ER-negative cancer were higher: 1.26 before age 30 years, 0.85 for age 30 to 35 years, and 0.45 to 0.65 for age 40 or older.

CONCLUSION

Results show a favorable decrease of 3% per year for CBC incidence in the United States since 1985. This overall trend was driven by declining CBC rates after an ER-positive cancer, possibly because of the widespread usage of adjuvant hormone therapies, after the results of the Nolvadex Adjuvant Trial Organisation were published in 1983, and/or other adjuvant treatments.

Association of age and overall survival in capecitabine-treated patients with metastatic breast cancer in clinical trials

We sought to determine if an association exists between age and capecitabine efficacy among patients with metastatic breast cancer (MBC). Pooled analysis of five phase II or III registration trials of capecitabine 2,500-2,510 mg/m(2)/day for 2 weeks and 1 week off, or combination therapy was performed. Four trials enrolled patients previously exposed to other chemotherapy, generally a taxane. Of 570 patients, 193 (34%) were 18-49 years old, 246 (43%) were 50-64, and 131 (23%) were ≥ 65. Median average daily dose was 2,067 mg/m² in the 18- to 49-year-old group and 2,105 mg/m² in the 50-64 and ≥ 65 year groups. Overall survival (OS) in all groups was similar by log-rank test for the individual trials (P = 0.71-0.95) and Cox regression of the pooled trials. Univariate analysis demonstrated no difference in clinical benefit or objective response between groups. Treatment failure analysis showed 283 (50%) patients experienced progressive disease, while 114 (20%) withdrew for safety. Serious adverse events (AEs) occurred in 71 (36.8%), 85 (34.6%), and 59 (45.0%) patients in the 18-49, 50-64, and ≥ 65 years groups, respectively. There was no statistically significant association between age and OS, clinical benefit, or objective response in patients with MBC treated with capecitabine. Frequency of AEs and serious AEs was not related to age at treatment, although women ≥ 65 years were more likely to withdraw from treatment because of an AE than younger women.

Expression of TGF-beta signaling factors in invasive breast cancers: relationships with age at diagnosis and tumor characteristics

The transforming growth factor beta (TGF-beta) pathway can play either a tumor-suppressing or a tumor-promoting role in human breast carcinogenesis. In order to determine whether expression of TGF-beta signaling factors varies by age at onset and breast tumor characteristics that have prognostic significance, we undertook a study of 623 women with invasive breast carcinoma enrolled in a population-based case-control study conducted in Poland from 2000 to 2003. TGF-beta signaling factors were analyzed by immunohistochemistry in tumor tissue microarrays. We found that most tumors expressed extracellular-TGF-beta1 (78%), TGF-beta2 (91%), TGF-beta3 (93%), TGF-betaR2 (72%), and phospho-SMAD2 (61%), whereas intracellular-TGF-beta1 was expressed in 32% of tumors. Expression of TGF-beta ligands (beta1, beta2, and beta3) was associated with prognostically favorable pathological features including small size, and low grade, and these associations were similar for ER-positive and negative tumors. On the contrary, expression of the receptor TGF-betaR2 was primarily associated with small tumor size among ER-negative tumors, while expression of the transcription factor phospho-SMAD2 was associated with positive nodal status among ER-negative tumors. The greater frequency of expression of phospho-SMAD2 in cancers associated with lymph node metastases is consistent with a pro-progression role for TGF-beta. In addition, expression of extracellular-TGF-beta1 (P = 0.005), TGF-betaR2 (P = 8.2E-11), and phospho-SMAD2 (P = 1.3E-8) was strongly associated with earlier age at onset, independent of ER status. Our data provide evidence that TGF-beta signaling patterns vary by age and pathologic features of prognostic significance including ER expression. These results warrant analysis in studies of clinical outcomes accounting for age, ER status and treatment.