Subtyping of breast cancer by immunohistochemistry to investigate a relationship between subtype and short and long term survival: a collaborative analysis of data for 10,159 cases from 12 studies

PREDICT Plus: development and validation of a prognostic model for early breast cancer that includes HER2

Background:

Predict (www.predict.nhs.uk) is an online, breast cancer prognostication and treatment benefit tool. The aim of this study was to incorporate the prognostic effect of HER2 status in a new version (Predict+), and to compare its performance with the original Predict and Adjuvant!.

Methods:

The prognostic effect of HER2 status was based on an analysis of data from 10 179 breast cancer patients from 14 studies in the Breast Cancer Association Consortium. The hazard ratio estimates were incorporated into Predict. The validation study was based on 1653 patients with early-stage invasive breast cancer identified from the British Columbia Breast Cancer Outcomes Unit. Predicted overall survival (OS) and breast cancer-specific survival (BCSS) for Predict+, Predict and Adjuvant! were compared with observed outcomes.

Results:

All three models performed well for both OS and BCSS. Both Predict models provided better BCSS estimates than Adjuvant!. In the subset of patients with HER2-positive tumours, Predict+ performed substantially better than the other two models for both OS and BCSS.

Conclusion:

Predict+ is the first clinical breast cancer prognostication tool that includes tumour HER2 status. Use of the model might lead to more accurate absolute treatment benefit predictions for individual patients.

Molecular subtypes of breast carcinoma in Egyptian women: clinicopathological features

Breast carcinoma may be classified into distinct molecular subtypes based on immunohistochemical markers for estrogen, progesterone and Her-2/neu receptors. The aim of the study was to identify the clinicopathological features of the molecular subtypes of breast carcinoma in our locality. A total of 274 surgically resected breast carcinomas were selected from the files of the Dr. KRZ referral pathology laboratory, Mansoura, Egypt, and the Pathology Department of Mansoura University. Molecular subtypes were classified into luminal A, luminal B, Her-2/neu-expressing and triple-negative. Clinicopathological and histological features of molecular subtypes were analyzed. Luminal A subtype was the most prevalent (41.2%), followed by triple-negative subtype (28.5%), then Her2-expressing subtype (19.4%) and luminal B subtype (13.9%). The commonest histological type was infiltrating duct carcinoma (83.2%), followed by infiltrating lobular carcinoma (9.1%) and medullary carcinoma (3.2%). The luminal A subtype was significantly correlated to low tumor grade, lower number of positive lymph nodes metastasis, absence of both necrosis and syncytial growth pattern. We concluded that the commonest molecular subtype of invasive breast carcinoma among Egyptian women is luminal subtype A, which displayed favorable features. Triple-negative subtype and medullary carcinomas are present in a ratio higher than in western countries.

Treatment of Metastatic Breast Cancer in Women Aged 65 Years and Older

Breast cancer is a disease of aging and the incidence of breast cancer increases dramatically with increasing age. In spite of major advances in prevention, screening and treatment approximately 40,000 Americans still die of metastatic breast cancer every year – the majority being women aged 65 years and older. Metastatic breast cancer remains incurable regardless of age and the goals of treatment are to reduce symptoms when present and to provide the patient with the best quality of life for as long as possible. Cornerstones of treatment to control metastases include endocrine therapy, chemotherapy and radiation therapy. Supportive care that includes psychosocial support and treatment of pain is also a key component of management. This review focuses on the issues related to the care of older women with metastatic breast cancer.

Differential response of immunohistochemically defined breast cancer subtypes to anthracycline-based adjuvant chemotherapy with or without paclitaxel

Background

The aim of the present study was to investigate the efficacy of adjuvant dose-dense sequential chemotherapy with epirubicin, paclitaxel, and CMF in subgroups of patients with high-risk operable breast cancer, according to tumor subtypes defined by immunohistochemistry (IHC).

Materials and Methods

Formalin-fixed paraffin-embedded (FFPE) tumor tissue samples from 1,039 patients participating in two adjuvant dose-dense sequential chemotherapy phase III trials were centrally assessed in tissue micro-arrays by IHC for 6 biological markers, that is, estrogen receptor (ER), progesterone receptor (PgR), HER2, Ki67, cytokeratin 5 (CK5), and EGFR. The majority of the cases were further evaluated for HER2 amplification by FISH. Patients were classified as: luminal A (ER/PgR-positive, HER2-negative, Ki67^low); luminal B (ER/PgR-positive, HER2-negative, Ki67^high); luminal-HER2 (ER/PgR-positive, HER2-positive); HER2-enriched (ER-negative, PgR-negative, HER2-positive); triple-negative (TNBC) (ER-negative, PgR-negative, HER2-negative); and basal core phenotype (BCP) (TNBC, CK5-positive and/or EGFR-positive).

Results

After a median follow-up time of 105.4 months the 5-year disease-free survival (DFS) and overall survival (OS) rates were 73.1% and 86.1%, respectively. Among patients with HER2-enriched tumors there was a significant benefit in both DFS and OS (log-rank test; p = 0.021 and p = 0.006, respectively) for those treated with paclitaxel. The subtype classification was found to be of both predictive and prognostic value. Setting luminal A as the referent category, the adjusted for prognostic factors HR for relapse for patients with TNBC was 1.91 (95% CI: 1.31–2.80, Wald's p = 0.001) and for death 2.53 (95% CI: 1.62–3.60, p<0.001). Site of and time to first relapse differed according to subtype. Locoregional relapses and brain metastases were more frequent in patients with TNBC, while liver metastases were more often seen in patients with HER2-enriched tumors.

Conclusions

Triple-negative phenotype is of adverse prognostic value for DFS and OS in patients treated with adjuvant dose-dense sequential chemotherapy. In the pre-trastuzumab era, the HER2-enriched subtype predicts favorable outcome following paclitaxel-containing treatment.

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.

Biological and prognostic associations of miR-205 and let-7b in breast cancer revealed by in situ hybridization analysis of micro-RNA expression in arrays of archival tumour tissue

Micro-RNAs (miRNAs) are frequently dysregulated in a range of human malignancies, many have been shown to act either as tumour supressors or oncogenes and several have been implicated in breast cancer. However, breast cancer is a diverse disease and little is known about the relationships between miRNA expression, clinical outcome and tumour subtype. We used locked nucleic acid probe in situ hybridization (LNA-ISH) to visualize, in tissue micro-arrays (TMAs) of 2919 formalin-fixed paraffin-embedded (FFPE) archival breast tumours, the expression of two key miRNAs that are frequently lost in a range of solid malignancies, let-7b and miR-205. These miRNAs were also quantified by quantitative reverse transcription PCR in cores of FFPE tissue from 40 of these cases, demonstrating that LNA-ISH is semi-quantitative. The tumours in the TMAs were assigned to subtypes based on their immunohistochemical (IHC) staining with ER, PR, HER2, CK5/6 and EGFR. let-7b expression was shown to be associated with luminal tumours and to have an independent significant positive prognostic value in this group. miR-205 is associated with tumours of ductal morphology and is of significant positive prognostic value within these tumours. We propose that the expression of miR-205 may contribute to ductal tumour morphology.

Biomarkers characterization of circulating tumour cells in breast cancer patients

Introduction

Increasing evidence supports the view that the detection of circulating tumor cells (CTCs) predicts outcomes of nonmetastatic breast cancer patients. CTCs differ genetically from the primary tumor and may contribute to variations in prognosis and response to therapy. As we start to understand more about the biology of CTCs, we can begin to address how best to treat this form of disease.

Methods

Ninety-eight nonmetastatic breast cancer patients were included in this study. CTCs were isolated by immunomagnetic techniques using magnetic beads labelled with a multi-CK-specific antibody (CK3-11D5) and CTC detection through immunocytochemical methods. Estrogen receptor, progesterone receptor and epidermal growth factor receptor (EGFR) were evaluated by immunofluorescence experiments and HER2 and TOP2A by fluorescence in situ hybridization. We aimed to characterize this set of biomarkers in CTCs and correlate it with clinical-pathological characteristics.

Results

Baseline detection rate was 46.9% ≥ 1 CTC/30 ml threshold. CTC-positive cells were more frequent in HER2-negative tumors (p = 0.046). In patients younger than 50 years old, HER2-amplified and G1-G2 tumors had a higher possibility of being nondetectable CTCs. Heterogeneous expression of hormonal receptors (HRs) in samples from the same patients was found. Discordances between HR expression, HER2 and TOP2A status in CTCs and their primary tumor were found in the sequential blood samples. Less that 35% of patients switched their CTC status after receiving chemotherapy. EGFR-positive CTCs were associated with Luminal tumors (p = 0.03).

Conclusions

This is the largest exploratory CTC biomarker analysis in nonmetastatic BC patients. Our study suggests that CTC biomarkers profiles might be useful as a surrogate marker for therapeutic selection and monitoring since heterogeneity of the biomarker distribution in CTCs and the lack of correlation with the primary tumor biomarker status were found. Further exploration of the association between EGFR-positive CTCs and Luminal tumors is warranted.

Tumour characteristics among women with very low-risk breast cancer

It has been proposed that a proportion of non-palpable breast cancers that are diagnosed through mammography represents a very low-risk subgroup of cancers that may not affect survival (overdiagnosis). The salient pathologic features of cancers in this theoretical subgroup are not known, and therefore, it is not possible to predict which patients have a cancer of this type. We reviewed the clinical characteristics and survival experiences of 715 patients with an invasive breast cancer of 5.0 cm or less. The tumour from each patient was represented in triplicate on a tissue microarray. Cases were divided into low-risk and moderate-/high-risk categories based on lymph node status and palpability. Low-risk cancers were those that were non-palpable, node-negative and were only detected by mammographic screening. All other cancers were high/moderate risk. The two groups of cancer patients were compared for a number of tumour characteristics, based on immunohistochemistry. There were 79 low-risk cancers and 636 moderate-/high-risk cancers. The low-risk cancers were characterized by ER-positivity, PR-positivity, HER2-negativity, ck5/6-negativity, EGFR-negativity and p53-negativity. About 54 of the 79 low-risk cancers (68 %) were of the luminal A subtype versus 335 of 636 moderate-/high-risk cancers (53 %; p = 0.008). Among 42 women with a non-palpable, mammogram-detected PR+ HER2- cancer of 5.0 cm or less, the 15-year distant recurrence-free survival rate was 100 %. Small breast cancers that are PR+ and HER2- and that are detectable by mammogram alone have a very low risk of recurrence. A proportion of these may represent examples of overdiagnosis.

Aurora kinase A outperforms Ki67 as a prognostic marker in ER-positive breast cancer

Background:

Proliferation has emerged as a major prognostic factor in luminal breast cancer. The immunohistochemical (IHC) proliferation marker Ki67 has been most extensively investigated but has not gained widespread clinical acceptance.

Methods:

We have conducted a head-to-head comparison of a panel of proliferation markers, including Ki67. Our aim was to establish the marker of the greatest prognostic utility. Tumour samples from 3093 women with breast cancer were constructed as tissue microarrays. We used IHC to detect expression of mini-chromosome maintenance protein 2, Ki67, aurora kinase A (AURKA), polo-like kinase 1, geminin and phospho-histone H3. We used a Cox proportional-hazards model to investigate the association with 10-year breast cancer-specific survival (BCSS). Missing values were resolved using multiple imputation.

Results:

The prognostic significance of proliferation was limited to oestrogen receptor (ER)-positive breast cancer. Aurora kinase A emerged as the marker of the greatest prognostic significance in a multivariate model adjusted for the standard clinical and molecular covariates (hazard ratio 1.3; 95% confidence interval 1.1–1.5; P=0.005), outperforming all other markers including Ki67.

Conclusion:

Aurora kinase A outperforms other proliferation markers as an independent predictor of BCSS in ER-positive breast cancer. It has the potential for use in routine clinical practice.

The genomic and transcriptomic architecture of 2,000 breast tumours reveals novel subgroups

The elucidation of breast cancer subgroups and their molecular drivers requires integrated views of the genome and transcriptome from representative numbers of patients. We present an integrated analysis of copy number and gene expression in a discovery and validation set of 997 and 995 primary breast tumours, respectively, with long-term clinical follow-up. Inherited variants (copy number variants and single nucleotide polymorphisms) and acquired somatic copy number aberrations (CNAs) were associated with expression in ~40% of genes, with the landscape dominated by cis- and trans-acting CNAs. By delineating expression outlier genes driven in cis by CNAs, we identified putative cancer genes, including deletions in PPP2R2A, MTAP and MAP2K4. Unsupervised analysis of paired DNA–RNA profiles revealed novel subgroups with distinct clinical outcomes, which reproduced in the validation cohort. These include a high-risk, oestrogen-receptor-positive 11q13/14 cis-acting subgroup and a favourable prognosis subgroup devoid of CNAs. Trans-acting aberration hotspots were found to modulate subgroup-specific gene networks, including a TCR deletion-mediated adaptive immune response in the ‘CNA-devoid’ subgroup and a basal-specific chromosome 5 deletion-associated mitotic network. Our results provide a novel molecular stratification of the breast cancer population, derived from the impact of somatic CNAs on the transcriptome.

The genomic and transcriptomic architecture of 2,000 breast tumours reveals novel subgroups

The elucidation of breast cancer subgroups and their molecular drivers requires integrated views of the genome and transcriptome from representative numbers of patients. We present an integrated analysis of copy number and gene expression in a discovery and validation set of 997 and 995 primary breast tumours, respectively, with long-term clinical follow-up. Inherited variants (copy number variants and single nucleotide polymorphisms) and acquired somatic copy number aberrations (CNAs) were associated with expression in ~40% of genes, with the landscape dominated by cis- and trans-acting CNAs. By delineating expression outlier genes driven in cis by CNAs, we identified putative cancer genes, including deletions in PPP2R2A, MTAP and MAP2K4. Unsupervised analysis of paired DNA–RNA profiles revealed novel subgroups with distinct clinical outcomes, which reproduced in the validation cohort. These include a high-risk, oestrogen-receptor-positive 11q13/14 cis-acting subgroup and a favourable prognosis subgroup devoid of CNAs. Trans-acting aberration hotspots were found to modulate subgroup-specific gene networks, including a TCR deletion-mediated adaptive immune response in the ‘CNA-devoid’ subgroup and a basal-specific chromosome 5 deletion-associated mitotic network. Our results provide a novel molecular stratification of the breast cancer population, derived from the impact of somatic CNAs on the transcriptome.

The clonal and mutational evolution spectrum of primary triple-negative breast cancers

Primary triple-negative breast cancers (TNBCs), a tumour type defined by lack of oestrogen receptor, progesterone receptor and ERBB2 gene amplification, represent approximately 16% of all breast cancers. Here we show in 104 TNBC cases that at the time of diagnosis these cancers exhibit a wide and continuous spectrum of genomic evolution, with some having only a handful of coding somatic aberrations in a few pathways, whereas others contain hundreds of coding somatic mutations. High-throughput RNA sequencing (RNA-seq) revealed that only approximately 36% of mutations are expressed. Using deep re-sequencing measurements of allelic abundance for 2,414 somatic mutations, we determine for the first time-to our knowledge-in an epithelial tumour subtype, the relative abundance of clonal frequencies among cases representative of the population. We show that TNBCs vary widely in their clonal frequencies at the time of diagnosis, with the basal subtype of TNBC showing more variation than non-basal TNBC. Although p53 (also known as TP53), PIK3CA and PTEN somatic mutations seem to be clonally dominant compared to other genes, in some tumours their clonal frequencies are incompatible with founder status. Mutations in cytoskeletal, cell shape and motility proteins occurred at lower clonal frequencies, suggesting that they occurred later during tumour progression. Taken together, our results show that understanding the biology and therapeutic responses of patients with TNBC will require the determination of individual tumour clonal genotypes.

Immunohistochemistry profiles of breast ductal carcinoma: factor analysis of digital image analysis data

BACKGROUND

Molecular studies of breast cancer revealed biological heterogeneity of the disease and opened new perspectives for personalized therapy. While multiple gene expression-based systems have been developed, current clinical practice is largely based upon conventional clinical and pathologic criteria. This gap may be filled by development of combined multi-IHC indices to characterize biological and clinical behaviour of the tumours. Digital image analysis (DA) with multivariate statistics of the data opens new opportunities in this field.

METHODS

Tissue microarrays of 109 patients with breast ductal carcinoma were stained for a set of 10 IHC markers (ER, PR, HER2, Ki67, AR, BCL2, HIF-1α, SATB1, p53, and p16). Aperio imaging platform with the Genie, Nuclear and Membrane algorithms were used for the DA. Factor analysis of the DA data was performed in the whole group and hormone receptor (HR) positive subgroup of the patients (n = 85).

RESULTS

Major factor potentially reflecting aggressive disease behaviour (i-Grade) was extracted, characterized by opposite loadings of ER/PR/AR/BCL2 and Ki67/HIF-1α. The i-Grade factor scores revealed bimodal distribution and were strongly associated with higher Nottingham histological grade (G) and more aggressive intrinsic subtypes. In HR-positive tumours, the aggressiveness of the tumour was best defined by positive Ki67 and negative ER loadings. High Ki67/ER factor scores were strongly associated with the higher G and Luminal B types, but also were detected in a set of G1 and Luminal A cases, potentially indicating high risk patients in these categories. Inverse relation between HER2 and PR expression was found in the HR-positive tumours pointing at differential information conveyed by the ER and PR expression. SATB1 along with HIF-1α reflected the second major factor of variation in our patients; in the HR-positive group they were inversely associated with the HR and BCL2 expression and represented the major factor of variation. Finally, we confirmed high expression levels of p16 in Triple-negative tumours.

CONCLUSION

Factor analysis of multiple IHC biomarkers measured by automated DA is an efficient exploratory tool clarifying complex interdependencies in the breast ductal carcinoma IHC profiles and informative value of single IHC markers. Integrated IHC indices may provide additional risk stratifications for the currently used grading systems and prove to be useful in clinical outcome studies.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1512077125668949.

Dose-dense chemotherapy versus conventional chemotherapy for early breast cancer: a systematic review with meta-analysis

BACKGROUND

Despite the widespread acceptance of dose-dense (DD) regimens as adjuvant chemotherapy for early breast cancer (EBC), studies of efficacy offer contradictory findings. This systematic review evaluates the real impact of DD chemotherapy.

METHODS

Randomized controlled trials comparing conventional adjuvant chemotherapy versus a DD regimen for EBC patients were searched in electronic databases. Dose-dense regimens included the same drugs and total amount as conventional chemotherapy, but applied in shorter intervals. Meta-analyses were performed using a fixed-effects model. Hazard ratios (HRs) or odds ratios (ORs) were expressed with 95% confidence intervals (95% CI). The outcomes were overall survival (OS), disease-free survival (DFS), and toxicities. Analyses were conducted according to tumor hormone receptor expression, plus tests for interaction.

RESULTS

Four studies (3418 patients) were included. The meta-analysis demonstrated that DD therapy can improve DFS (3356 patients; HR=0.83; 95% CI 0.73-0.95; p=0.005), independent of hormone receptor expression status. There was no OS benefit with DD therapy (3356 patients; HR=0.86; 95% CI 0.73-1.01; p=0.06) irrespective of tumor hormone receptor status (OS in hormone-positive stratum HR=0.94; 95% CI 0.74-1.21; OS in hormone-negative stratum HR=0.78; 95% CI 0.62-0.99; interaction test p=0.28). DD regimens caused a small increase in anemia and mucositis, but had no impact on cardiac events, leukemia or myelodysplasia.

CONCLUSIONS

DD adjuvant chemotherapy can improve DFS of EBC patients with little impact on safety. However there is no clear benefit in OS. Further research may indicate if there is any impact on OS not presently seen due to small sample size, and which patients may derive greater benefit.

CD8+ lymphocyte infiltration is an independent favorable prognostic indicator in basal-like breast cancer

Introduction

Tumor infiltrating lymphocytes may indicate an immune response to cancer development, but their significance remains controversial in breast cancer. We conducted this study to assess CD8+ (cytotoxic T) lymphocyte infiltration in a large cohort of invasive early stage breast cancers, and to evaluate its prognostic effect in different breast cancer intrinsic subtypes.

Methods

Immunohistochemistry for CD8 staining was performed on tissue microarrays from 3992 breast cancer patients. CD8+ tumor infiltrating lymphocytes were counted as intratumoral when in direct contact with tumor cells, and as stromal in adjacent locations. Kaplan-Meier functions and Cox proportional hazards regression models were applied to examine the associations between tumor infiltrating lymphocytes and breast cancer specific survival.

Results

Among 3403 cases for which immunohistochemical results were obtained, CD8+ tumor infiltrating lymphocytes were identified in an intratumoral pattern in 32% and stromal pattern in 61% of the cases. In the whole cohort, the presence of intratumoral tumor-infiltrating lymphocytes was significantly correlated with young age, high grade, estrogen receptor negativity, human epidermal growth factor receptor-2 positivity and core basal intrinsic subtype, and was associated with superior breast cancer specific survival. Multivariate analysis indicated that the favorable prognostic effect of CD8+ tumor infiltrating lymphocytes was significant only in the core basal intrinsic subgroup (Hazard ratio, HR = 0.35, 95% CI = 0.23-0.54). No association with improved survival was present in those triple negative breast cancers that lack expression of basal markers (HR = 0.99, 95% CI = 0.48-2.04) nor in the other intrinsic subtypes.

Conclusions

CD8+ tumor infiltrating lymphocytes are an independent prognostic factor associated with better patient survival in basal-like breast cancer, but not in non-basal triple negative breast cancers nor in other intrinsic molecular subtypes.

Lectin chromatography/mass spectrometry discovery workflow identifies putative biomarkers of aggressive breast cancers

We used a lectin chromatography/MS-based approach to screen conditioned medium from a panel of luminal (less aggressive) and triple negative (more aggressive) breast cancer cell lines (n=5/subtype). The samples were fractionated using the lectins Aleuria aurantia (AAL) and Sambucus nigra agglutinin (SNA), which recognize fucose and sialic acid, respectively. The bound fractions were enzymatically N-deglycosylated and analyzed by LC-MS/MS. In total, we identified 533 glycoproteins, ∼90% of which were components of the cell surface or extracellular matrix. We observed 1011 glycosites, 100 of which were solely detected in ≥3 triple negative lines. Statistical analyses suggested that a number of these glycosites were triple negative-specific and thus potential biomarkers for this tumor subtype. An analysis of RNaseq data revealed that approximately half of the mRNAs encoding the protein scaffolds that carried potential biomarker glycosites were up-regulated in triple negative vs luminal cell lines, and that a number of genes encoding fucosyl- or sialyltransferases were differentially expressed between the two subtypes, suggesting that alterations in glycosylation may also drive candidate identification. Notably, the glycoproteins from which these putative biomarker candidates were derived are involved in cancer-related processes. Thus, they may represent novel therapeutic targets for this aggressive tumor subtype.

BRCA1 testing should be offered to individuals with triple-negative breast cancer diagnosed below 50 years

BACKGROUND

Triple-negative (TN) tumours are the predominant breast cancer subtype in BRCA1 mutation carriers. Recently, it was proposed that all individuals below 50 years of age with TN breast cancer should be offered BRCA testing. We have evaluated the BRCA1 mutation frequency and the implications for clinical practice of undertaking genetic testing in women with TN breast cancer.

METHODS

We undertook BRCA1 mutation analysis in 308 individuals with TN breast cancer, 159 individuals from unselected series of breast cancer and 149 individuals from series ascertained on the basis of young age and/or family history.

RESULTS

BRCA1 mutations were present in 45 out of 308 individuals. Individuals with TN cancer <50 years had >10% likelihood of carrying a BRCA1 mutation in both the unselected (11 out of 58, 19%) and selected (26 out of 111, 23%) series. However, over a third would not have been offered testing using existing criteria. We estimate that testing all individuals with TN breast cancer <50 years would generate an extra 1200 tests annually in England.

CONCLUSION

Women with TN breast cancer diagnosed below 50 years have >10% likelihood of carrying a BRCA1 mutation and are therefore eligible for testing in most centres. However, implementation may place short-term logistical and financial burdens on genetic services.

Dietary tocopherols inhibit cell proliferation, regulate expression of ERα, PPARγ, and Nrf2, and decrease serum inflammatory markers during the development of mammary hyperplasia

Previous clinical and epidemiological studies of vitamin E have used primarily α-tocopherol for the prevention of cancer. However, γ-tocopherol has demonstrated greater anti-inflammatory and anti-tumor activity than α-tocopherol in several animal models of cancer. This study assessed the potential chemopreventive activities of a tocopherol mixture containing 58% γ-tocopherol (γ-TmT) in an established rodent model of mammary carcinogenesis. Female ACI rats were utilized due to their sensitivity to 17β-estradiol (E2 ) to induce mammary hyperplasia and neoplasia. The rats were implanted subcutaneously with sustained release E2 pellets and given dietary 0.3% or 0.5% γ-TmT for 2 or 10 wk. Serum E2 levels were significantly reduced by the treatment with 0.5% γ-TmT. Serum levels of inflammatory markers, prostaglandin E2 and 8-isoprostane, were suppressed by γ-TmT treatment. Histology of mammary glands showed evidence of epithelial hyperplasia in E2 -treated rats. Immunohistochemical analysis of the mammary glands revealed a decrease in proliferating cell nuclear antigen (PCNA), cyclooxygenase-2 (COX-2), and estrogen receptor α (ERα), while there was an increase in cleaved-caspase 3, peroxisome proliferator-activated receptor γ (PPARγ), and nuclear factor (erythroid-derived 2)-like 2 (Nrf2) in γ-TmT-treated rats. In addition, treatment with γ-TmT resulted in a decrease in the expression of ERα mRNA, whereas mRNA levels of ERβ and PPARγ were increased. In conclusion, γ-TmT was shown to suppress inflammatory markers, inhibit E2 -induced cell proliferation, and upregulate PPARγ and Nrf2 expression in mammary hyperplasia, suggesting that γ-TmT may be a promising agent for human breast cancer prevention.

Patient survival and healthcare utilization costs after diagnosis of triple-negative breast cancer in a United States managed care cancer registry

BACKGROUND

Triple-negative breast cancer (TNBC) makes up 10-17% of all breast cancers and, due to lack of receptor expression, is unresponsive to therapies that target hormonal receptors or HER2. Unique in its tumor aggression and high rates of recurrence, TNBC is less likely to be detected by mammogram and has a poorer prognosis than other breast cancer subtypes (non-TNBC).

OBJECTIVES

To examine the survival, healthcare utilization, and healthcare cost for women with TNBC compared with non-TNBC breast cancer.

METHODS

The study population was derived from a US managed care cancer registry linked to health insurance claims and social security mortality data. Based on initial type and stage at diagnosis, patients were divided into two cohorts: patients with TNBC and those with non-TNBC. Records were analyzed from initial diagnosis until death, disenrollment, or end of observation period. Survival and annual healthcare utilization and costs were estimated and compared between cohorts after adjusting for baseline demographic characteristics, comorbidities, and prior resource use. Subgroup analyses were performed in patients diagnosed with stage I-III and IV breast cancer.

RESULTS

The study included women diagnosed with TNBC (n = 450) and non-TNBC (n = 1807). Median follow-up time for all patients was 716 days (688.5 and 733 days for TNBC and non-TNBC patients, respectively). After initial diagnosis, overall mortality risk for the TNBC cohort was twice as high as the non-TNBC cohort (HR = 2.02, p < 0.0001). Patients with TNBC had more annual hospitalizations, hospitalized days, and number of emergency room visits relative to non-TNBC. Despite similar annual total healthcare costs, adjusted inpatient costs for patients with non-TNBC averaged 77% higher ($8395 vs. $4745, p < 0.0001). Furthermore, payer reimbursements were higher for TNBC than non-TNBC patients ($8213 vs. $4486, p < 0.0001).

CONCLUSIONS

While it does not control for race or socioeconomic status, this study found that in a US managed care setting, patients with TNBC compared with non-TNBC have significantly shorter survival, accompanied by higher inpatient utilization and healthcare costs.

Clinicopathologic characteristics and prognosis for molecular subtypes in low-grade breast carcinoma: comparison with grade one invasive ductal carcinoma-not otherwise specified

The aim of this study was to investigate the clinicopathologic characteristics and prognosis value for molecular subtypes of low-grade breast carcinoma (LGBC) compared with grade one invasive ductal carcinoma-not otherwise specified (G1-IDC-NOS). A retrospective review of 688 LGBC and 1 037 G1-IDC-NOS patients was classified into four different molecular subtypes based on the IHC-based definitions for ER, PR, and c-erbB-2. In LGBC, lymph node metastasis, the percentage of III/IV TNM stages, the expression of Ki-67 and p53 in luminal A subtype were lower than in other subtypes (P<0.01). In addition, the variations of Ki-67 and p53 expression were observed in different subtypes of G1-IDC-NOS (P<0.01). Compared with G1-IDC-NOS, LGBC has higher proportion in the ER positive, PR positive, HER-2 negative, luminal A subtype, Ki-67 negative, and lymph nodes negative group (P<0.01). Furthermore, the overall survival of luminal A and luminal B is higher than triple-negative and HER-2/neu subtype both in LGBC and G1-IDC-NOS in 262 LGBC and 330 G1-IDC-NOS patients with proper follow-up. The classification of molecular subtype together with clinicopathologic factors can significantly improve the traditional prognosticators in predicting outcome for LGBC and G1-IDC-NOS. And it may contribute to guide the treatment for LGBC and G1-IDC-NOS in the future.

A gene signature for predicting outcome in patients with basal-like breast cancer

Basal-like breast cancer is a molecular subtype of breast cancer with a poor prognosis. Follow-up studies of long-term outcome in these patients, demonstrates they can be separated into two clinical groups: those who succumb to their disease within the first 5 years and those expected to show excellent long term survival. Currently available clinical/histopathological variables as well as molecular signatures show little capacity to identify basal breast cancer patients with either a high or low risk of disease relapse. Using data derived from 85 basal-like breast cancer patients, we identified a 14-gene signature, which we subsequently validated on an additional 49 basal breast cancer patient set. The ability to distinguish between these two sub-groups of basal breast cancer patients at the time of initial diagnosis would permit tailoring aggressive therapeutic regimens to those patients with a poor prognosis and conversely avoid such therapy in low risk patients.

Angiopoietins 1 and 2 and Tie-2 receptor expression in human ductal breast disease

AIMS

 This study aimed to identify the involvement of the angiopoietin/Tie-2 receptor system in breast cancer development, progression, metastasis and angiogenesis.

METHODS AND RESULTS

We quantified and correlated angiopoietin-1 (Ang-1), Ang-2 and Tie-2 expression in sections of normal human breast, benign and premalignant hyperplastic tissue, pre-invasive and invasive cancer, and compared these findings with our previously published data on vascular endothelial growth factor (VEGF) and microvessel density (MVD) in the same samples. A breast cancer tissue microarray was used to evaluate the prognostic value of these factors. Histological analysis revealed a significant decrease in Ang-1 expression (P = 0.001) and an inverse correlation with MVD (r = -0.442, P = 0.008) and VEGF (r = -0.510, P = 0.002) in the non-invasive lesions. In contrast Ang-2 expression increased significantly (P = 0.0004) with increasing severity of lesion and correlated with MVD (r = 0.570; P = 0.0002), while Tie-2 expression remained relatively unchanged. Expression of all three factors was reduced in invasive breast cancer and did not correlate with oestrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), lymph node status or tumour grade.

CONCLUSIONS

These data suggest that a change in the angiopoietin balance in favour of Ang-2 is associated with the angiogenic switch at the onset of hyperplasia in the breast. However, angiopoietins and the Tie-2 receptor are not related to known prognostic indicators in invasive breast cancer.

Eight-Signature Classifier for Prediction of Nasopharyngeal Carcinoma Survival

Purpose

Currently, nasopharyngeal carcinoma (NPC) prognosis evaluation is based primarily on the TNM staging system. This study aims to identify prognostic markers for NPC.

Patients and Methods

We detected expression of 18 biomarkers by immunohistochemistry in NPC tumors from 209 patients and evaluated the association between gene expression level and disease-specific survival (DSS). We used support vector machine (SVM) –based methods to develop a prognostic classifier for NPC (NPC-SVM classifier). Further validation of the NPC-SVM classifier was performed in an independent cohort of 1,059 patients.

Results

The NPC-SVM classifier integrated patient sex and the protein expression level of seven genes, including Epstein-Barr virus latency membrane protein 1, CD147, caveolin-1, phospho-P70S6 kinase, matrix metalloproteinase 11, survivin, and secreted protein acidic and rich in cysteine. The NPC-SVM classifier distinguished patients with NPC into low- and high-risk groups with significant differences in 5-year DSS in the evaluated patients (87% v 37.7%; P < .001) in the validation cohort. In multivariate analysis adjusted for age, TNM stage, and histologic subtype, the NPC-SVM classifier was an independent predictor of 5-year DSS in the evaluated patients (hazard ratio, 4.9; 95% CI, 3.0 to 7.9) in the validation cohort.

Conclusion

As a powerful predictor of 5-year DSS among patients with NPC, the newly developed NPC-SVM classifier based on tumor-associated biomarkers will facilitate patient counseling and individualize management of patients with NPC.

Cancer stem cell markers in breast cancer: pathological, clinical and prognostic significance

INTRODUCTION

The cancer stem cell (CSC) hypothesis states that tumours consist of a cellular hierarchy with CSCs at the apex driving tumour recurrence and metastasis. Hence, CSCs are potentially of profound clinical importance. We set out to establish the clinical relevance of breast CSC markers by profiling a large cohort of breast tumours in tissue microarrays (TMAs) using immunohistochemistry (IHC).

METHODS

We included 4, 125 patients enrolled in the SEARCH population-based study with tumours represented in TMAs and classified into molecular subtype according to a validated IHC-based five-marker scheme. IHC was used to detect CD44/CD24, ALDH1A1, aldehyde dehydrogenase family 1 member A3 (ALDH1A3) and integrin alpha-6 (ITGA6). A 'Total CSC' score representing expression of all four CSC markers was also investigated. Association with breast cancer specific survival (BCSS) at 10 years was assessed using a Cox proportional-hazards model. This study was complied with REMARK criteria.

RESULTS

In ER negative cases, multivariate analysis showed that ITGA6 was an independent prognostic factor with a time-dependent effect restricted to the first two years of follow-up (hazard ratio (HR) for 0 to 2 years follow-up, 2.4; 95% confidence interval (95% CI), 1.2 to 4.8; P = 0.009). The composite 'Total CSC' score carried independent prognostic significance in ER negative cases for the first four years of follow-up (HR for 0 to 4 years follow-up, 1.3; 95% CI, 1.1 to 1.6; P = 0.006).

CONCLUSIONS

Breast CSC markers do not identify identical subpopulations in primary tumours. Both ITGA6 and a composite Total CSC score show independent prognostic significance in ER negative disease. The use of multiple markers to identify tumours enriched for CSCs has the greatest prognostic value. In the absence of more specific markers, we propose that the effective translation of the CSC hypothesis into patient benefit will necessitate the use of a panel of markers to robustly identify tumours enriched for CSCs.

A comparative biomarker study of 514 matched cases of male and female breast cancer reveals gender-specific biological differences

Male breast cancer remains understudied despite evidence of rising incidence. Using a co-ordinated multi-centre approach, we present the first large scale biomarker study to define and compare hormone receptor profiles and survival between male and female invasive breast cancer. We defined and compared hormone receptor profiles and survival between 251 male and 263 female breast cancers matched for grade, age, and lymph node status. Tissue microarrays were immunostained for ERα, ERβ1, -2, -5, PR, PRA, PRB and AR, augmented by HER2, CK5/6, 14, 18 and 19 to assist typing. Hierarchical clustering determined differential nature of influences between genders. Luminal A was the most common phenotype in both sexes. Luminal B and HER2 were not seen in males. Basal phenotype was infrequent in both. No differences in overall survival at 5 or 10 years were observed between genders. Notably, AR-positive luminal A male breast cancer had improved overall survival over female breast cancer at 5 (P = 0.01, HR = 0.39, 95% CI = 0.26-0.87) but not 10 years (P = 0.29, HR = 0.75, 95% CI = 0.46-1.26) and both 5 (P = 0.04, HR = 0.37, 95% CI = 0.07-0.97) and 10 years (P = 0.04, HR = 0.43, 95% CI = 0.12-0.97) in the unselected group. Hierarchical clustering revealed common clusters between genders including total PR-PRA-PRB and ERβ1/2 clusters. A striking feature was the occurrence of ERα on distinct clusters between genders. In female breast cancer, ERα clustered with PR and its isoforms; in male breast cancer, ERα clustered with ERβ isoforms and AR. Our data supports the hypothesis that breast cancer is biologically different in males and females suggesting implications for clinical management. With the incidence of male breast cancer increasing this provides impetus for further study.

Targeted therapies: how personal should we go?

Despite the development of drugs inhibiting the oncogenic proteins that cancer cells are dependent on, attempts to match targeted therapies to the genetic makeup of individual tumors is proving more difficult than expected. Until now, the paradigm has been a binary correlation between a mutated cancer gene and response to a given therapy. However, recent evidence indicates that different genetic alterations, such as mutations in different codons of a cancer gene, might be related to distinct sensitivity to targeted therapies. An example is the divergent effect that individual EGFR, PIK3CA and KRAS mutations might have on response or resistance to tailored drugs. Furthermore, the idea that the presence of a specific mutation translates into sensitivity or resistance to a particular drug is likely too simplistic, since it does not capture the complexity of the signaling pathways in an individual cancer. Only the overall genetic milieu (alterations in upstream and/or parallel pathways) ultimately determines the response of individual tumors to therapy. We have critically analyzed data supporting the genetic, biological and biochemical differences of individual mutations within a single cancer gene. The role of cancer mutations as predictors of sensitivity and resistance to targeted therapies is discussed, together with the implications for the 'personalized' treatment of cancer patients.

Chemopreventive activity of vitamin E in breast cancer: a focus on γ- and δ-tocopherol

Vitamin E consists of eight different variants: α-, β-, γ-, and δ-tocopherols (saturated phytyl tail) and α-, β-, γ-, and δ-tocotrienols (unsaturated phytyl tail). Cancer prevention studies with vitamin E have primarily utilized the variant α-tocopherol. To no avail, a majority of these studies focused on variant α-tocopherol with inconsistent results. However, γ-tocopherol, and more recently δ-tocopherol, have shown greater ability to reduce inflammation, cell proliferation, and tumor burden. Recent results have shown that γ-enriched mixed tocopherols inhibit the development of mammary hyperplasia and tumorigenesis in animal models. In this review, we discuss the possible differences between the variant forms, molecular targets, and cancer-preventive effects of tocopherols. We recommend that a γ-enriched mixture, γ- and δ-tocopherol, but not α-tocopherol, are promising agents for breast cancer prevention and warrant further investigation.

Do anthracyclines still have a role in adjuvant chemotherapy of breast cancer?

Anthracycline-based regimens became the standard of care for early breast cancer patients based on the survival advantage they provide over nonanthracycline-containing regimens. The addition of taxanes, and subsequently trastuzumab in HER2-overexpressing patients, to anthracyclines further improved their efficacy in several studies involving high-risk early breast cancer patients. Concern over toxicity initially surfaced after anthracyclines were reported to carry an increased risk of cardiotoxicity and secondary leukemia. Trastuzumab has since been shown to compound the risk of cardiotoxicity in patients who have received an anthracycline. This has led to the development of regimens featuring a taxane without an anthracycline; these protocols vary in design and have different toxicity and efficacy profiles. Ongoing investigations are centered on the optimization of nonanthracycline regimens, prospective exploration of molecular markers to identify populations of patients who will derive maximal benefit from anthracycline-based chemotherapy, and the identification of less cardiotoxic formulations of existing anthracycline agents. Perhaps most importantly, a rapidly growing understanding of the biological heterogeneity of breast cancer is likely to lead to an individualized standard of care guided by particular patient and tumor characteristics.

Ki-67: level of evidence and methodological considerations for its role in the clinical management of breast cancer: analytical and critical review

Clinicians can use biomarkers to guide therapeutic decisions in estrogen receptor positive (ER+) breast cancer. One such biomarker is cellular proliferation as evaluated by Ki-67. This biomarker has been extensively studied and is easily assayed by histopathologists but it is not currently accepted as a standard. This review focuses on its prognostic and predictive value, and on methodological considerations for its measurement and the cut-points used for treatment decision. Data describing study design, patients’ characteristics, methods used and results were extracted from papers published between January 1990 and July 2010. In addition, the studies were assessed using the REMARK tool. Ki-67 is an independent prognostic factor for disease-free survival (HR 1.05–1.72) in multivariate analyses studies using samples from randomized clinical trials with secondary central analysis of the biomarker. The level of evidence (LOE) was judged to be I-B with the recently revised definition of Simon. However, standardization of the techniques and scoring methods are needed for the integration of this biomarker in everyday practice. Ki-67 was not found to be predictive for long-term follow-up after chemotherapy. Nevertheless, high KI-67 was found to be associated with immediate pathological complete response in the neoadjuvant setting, with an LOE of II-B. The REMARK score improved over time (with a range of 6–13/20 vs. 10–18/20, before and after 2005, respectively). KI-67 could be considered as a prognostic biomarker for therapeutic decision. It is assessed with a simple assay that could be standardized. However, international guidelines are needed for routine clinical use.

Breast tumors from CHEK2 1100delC-mutation carriers: genomic landscape and clinical implications

INTRODUCTION

Checkpoint kinase 2 (CHEK2) is a moderate penetrance breast cancer risk gene, whose truncating mutation 1100delC increases the risk about twofold. We investigated gene copy-number aberrations and gene-expression profiles that are typical for breast tumors of CHEK2 1100delC-mutation carriers.

METHODS

In total, 126 breast tumor tissue specimens including 32 samples from patients carrying CHEK2 1100delC were studied in array-comparative genomic hybridization (aCGH) and gene-expression (GEX) experiments. After dimensionality reduction with CGHregions R package, CHEK2 1100delC-associated regions in the aCGH data were detected by the Wilcoxon rank-sum test. The linear model was fitted to GEX data with R package limma. Genes whose expression levels were associated with CHEK2 1100delC mutation were detected by the bayesian method.

RESULTS

We discovered four lost and three gained CHEK2 1100delC-related loci. These include losses of 1p13.3-31.3, 8p21.1-2, 8p23.1-2, and 17p12-13.1 as well as gains of 12q13.11-3, 16p13.3, and 19p13.3. Twenty-eight genes located on these regions showed differential expression between CHEK2 1100delC and other tumors, nominating them as candidates for CHEK2 1100delC-associated tumor-progression drivers. These included CLCA1 on 1p22 as well as CALCOCO1, SBEM, and LRP1 on 12q13. Altogether, 188 genes were differentially expressed between CHEK2 1100delC and other tumors. Of these, 144 had elevated and 44, reduced expression levels.Our results suggest the WNT pathway as a driver of tumorigenesis in breast tumors of CHEK2 1100delC-mutation carriers and a role for the olfactory receptor protein family in cancer progression. Differences in the expression of the 188 CHEK2 1100delC-associated genes divided breast tumor samples from three independent datasets into two groups that differed in their relapse-free survival time.

CONCLUSIONS

We have shown that copy-number aberrations of certain genomic regions are associated with CHEK2 mutation 1100delC. On these regions, we identified potential drivers of CHEK2 1100delC-associated tumorigenesis, whose role in cancer progression is worth investigating. Furthermore, poorer survival related to the CHEK2 1100delC gene-expression signature highlights pathways that are likely to have a role in the development of metastatic disease in carriers of the CHEK2 1100delC mutation.

Prognostic value of basal phenotype in HER2-overexpressing breast cancer

BACKGROUND

Primary breast cancers that overexpress human epidermal growth factor receptor 2 have variable biological features and clinical outcomes. A subgroup of HER2-overexpressing tumors that express basal-like immunohistochemical markers-the so-called basal-HER2+ subtype--is associated with poor prognosis. We investigated the clinical relevance of this basal-HER2+ subtype within HER2-overexpressing breast tumors.

METHODS

Database review identified consecutive patients with HER2-overexpressing breast cancer. Archival tumor specimens from these patients were immunostained for estrogen receptor (ER), HER2, and basal cytokeratin (CK) expression, then subtyped as luminal-HER2+ (ER positive and basal CK negative), HER2+ (ER negative and basal CK negative), and basal-HER2+ (ER negative and basal CK positive). Subtypes were correlated with clinicopathologic features and overall survival.

RESULTS

Immunohistochemical assessment of 131 HER2-overexpressing breast tumors identified 79 (60%) luminal-HER2+ tumors, 40 (31%) HER2+ tumors, and 12 (9%) basal-HER2+ tumors. There was no difference in the use of adjuvant trastuzumab and chemotherapy among patients with these subtypes. Five-year overall survival was 65% for patients with basal-HER2+ tumors versus 94% (P = 0.0035) and 96% (P = 0.0031) for patients with luminal-HER2+ and HER2+ tumors, respectively. The basal-HER2+ subtype was associated with the worst prognosis after adjusting for age, tumor size, lymph node status, and adjuvant treatment (hazard ratio 5.06, 95% confidence interval 1.1-23.2, P = 0.037).

CONCLUSIONS

The basal-HER2+ subtype highlights the heterogeneous biology of HER2-overexpressing breast cancer. The basal-HER2+ subtype is independently associated with poor survival and may provide insight into breast cancer cell response to anti-HER2 therapy.

Low penetrance breast cancer susceptibility loci are associated with specific breast tumor subtypes: findings from the Breast Cancer Association Consortium

Breast cancers demonstrate substantial biological, clinical and etiological heterogeneity. We investigated breast cancer risk associations of eight susceptibility loci identified in GWAS and two putative susceptibility loci in candidate genes in relation to specific breast tumor subtypes. Subtypes were defined by five markers (ER, PR, HER2, CK5/6, EGFR) and other pathological and clinical features. Analyses included up to 30 040 invasive breast cancer cases and 53 692 controls from 31 studies within the Breast Cancer Association Consortium. We confirmed previous reports of stronger associations with ER+ than ER- tumors for six of the eight loci identified in GWAS: rs2981582 (10q26) (P-heterogeneity = 6.1 × 10(-18)), rs3803662 (16q12) (P = 3.7 × 10(-5)), rs13281615 (8q24) (P = 0.002), rs13387042 (2q35) (P = 0.006), rs4973768 (3p24) (P = 0.003) and rs6504950 (17q23) (P = 0.002). The two candidate loci, CASP8 (rs1045485, rs17468277) and TGFB1 (rs1982073), were most strongly related with the risk of PR negative tumors (P = 5.1 × 10(-6) and P = 4.1 × 10(-4), respectively), as previously suggested. Four of the eight loci identified in GWAS were associated with triple negative tumors (P ≤ 0.016): rs3803662 (16q12), rs889312 (5q11), rs3817198 (11p15) and rs13387042 (2q35); however, only two of them (16q12 and 2q35) were associated with tumors with the core basal phenotype (P ≤ 0.002). These analyses are consistent with different biological origins of breast cancers, and indicate that tumor stratification might help in the identification and characterization of novel risk factors for breast cancer subtypes. This may eventually result in further improvements in prevention, early detection and treatment.

Strategies for subtypes--dealing with the diversity of breast cancer: highlights of the St. Gallen International Expert Consensus on the Primary Therapy of Early Breast Cancer 2011

The 12th St Gallen International Breast Cancer Conference (2011) Expert Panel adopted a new approach to the classification of patients for therapeutic purposes based on the recognition of intrinsic biological subtypes within the breast cancer spectrum. For practical purposes, these subtypes may be approximated using clinicopathological rather than gene expression array criteria. In general, systemic therapy recommendations follow the subtype classification. Thus, 'Luminal A' disease generally requires only endocrine therapy, which also forms part of the treatment of the 'Luminal B' subtype. Chemotherapy is considered indicated for most patients with 'Luminal B', 'Human Epidermal growth factor Receptor 2 (HER2) positive', and 'Triple negative (ductal)' disease, with the addition of trastuzumab in 'HER2 positive' disease. Progress was also noted in defining better tolerated local therapies in selected cases without loss of efficacy, such as accelerated radiation therapy and the omission of axillary dissection under defined circumstances. Broad treatment recommendations are presented, recognizing that detailed treatment decisions need to consider disease extent, host factors, patient preferences, and social and economic constraints.

Nottingham Prognostic Index in triple-negative breast cancer: a reliable prognostic tool?

BACKGROUND

A breast cancer prognostic tool should ideally be applicable to all types of invasive breast lesions. A number of studies have shown histopathological grade to be an independent prognostic factor in breast cancer, adding prognostic power to nodal stage and tumour size. The Nottingham Prognostic Index has been shown to accurately predict patient outcome in stratified groups with a follow-up period of 15 years after primary diagnosis of breast cancer. Clinically, breast tumours that lack the expression of Oestrogen Receptor, Progesterone Receptor and Human Epidermal growth factor Receptor 2 (HER2) are identified as presenting a "triple-negative" phenotype or as triple-negative breast cancers. These poor outcome tumours represent an easily recognisable prognostic group of breast cancer with aggressive behaviour that currently lack the benefit of available systemic therapy. There are conflicting results on the prevalence of lymph node metastasis at the time of diagnosis in triple-negative breast cancer patients but it is currently accepted that triple-negative breast cancer does not metastasize to axillary nodes and bones as frequently as the non-triple-negative carcinomas, favouring instead, a preferentially haematogenous spread. Hypothetically, this particular tumour dissemination pattern would impair the reliability of using Nottingham Prognostic Index as a tool for triple-negative breast cancer prognostication.

METHODS

The present study tested the effectiveness of the Nottingham Prognostic Index in stratifying breast cancer patients of different subtypes with special emphasis in a triple-negative breast cancer patient subset versus non- triple-negative breast cancer.

RESULTS

We demonstrated that besides the fact that TNBC disseminate to axillary lymph nodes as frequently as luminal or HER2 tumours, we also showed that TNBC are larger in size compared with other subtypes and almost all grade 3. Additionally, survival curves demonstrated that these prognostic factors are equally important to stratify different survival outcomes in non-TNBC as in TNBC. We also showed that the NPI retains the ability to stratify and predict survival of TNBC patients.

CONCLUSION

The importance of this study relies on the need of prognostication improvements on TNBC, showing, at a clinical standpoint, that Nottingham Prognostic Index is as a truthful prognostic tool in TNBC.

Androgen receptor expression in breast cancer in relation to molecular phenotype: results from the Nurses' Health Study

Previous studies have demonstrated that androgen receptor is expressed in many breast cancers, but its expression in relation to the various breast cancer subtypes as defined by molecular profiling has not been studied in detail. We constructed tissue microarrays from 3093 breast cancers that developed in women enrolled in the Nurses' Health Study. Tissue microarray sections were immunostained for estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), cytokeratin 5/6, epidermal growth factor receptor (EGFR) and androgen receptor (ER). Immunostain results were used to categorize each cancer as luminal A or B, HER2 and basal like. The relationships between androgen receptor expression and molecular subtype were analyzed. Overall, 77% of the invasive breast carcinomas were androgen receptor positive. Among 2171 invasive cancers, 64% were luminal A, 15% luminal B, 6% HER2 and 11% basal like. The frequency of androgen receptor expression varied significantly across the molecular phenotypes (P<0.0001). In particular, androgen receptor expression was commonly observed in luminal A (91%) and B (68%) cancers, but was less frequently seen in HER2 cancers (59%). Despite being defined by the absence of ER and PR expression and being considered hormonally unresponsive, 32% of basal-like cancers expressed androgen receptor. Among 246 cases of ductal carcinoma in situ, 86% were androgen receptor positive, but the frequency of androgen receptor expression differed significantly across the molecular phenotypes (P=0.001), and high nuclear grade lesions were less likely to be androgen receptor positive compared with lower-grade lesions. Androgen receptor expression is most commonly seen in luminal A and B invasive breast cancers. However, expression of androgen receptor is also seen in approximately one-third of basal-like cancers, providing further evidence that basal-like cancers represent a heterogeneous group. Our findings raise the possibility that targeting the androgen receptor pathway may represent a novel therapeutic approach to the management of patients with basal-like cancers.

The After Breast Cancer Pooling Project: rationale, methodology, and breast cancer survivor characteristics

The After Breast Cancer Pooling Project was established to examine the role of physical activity, adiposity, dietary factors, supplement use, and quality of life (QOL) in breast cancer prognosis. This paper presents pooled and harmonized data on post-diagnosis lifestyle factors, clinical prognostic factors, and breast cancer outcomes from four prospective cohorts of breast cancer survivors (three US-based and one from Shanghai, China) for 18,314 invasive breast cancer cases diagnosed between 1976 and 2006. Most participants were diagnosed with stage I-II breast cancer (84.7%). About 60% of breast tumors were estrogen receptor (ER)+/progesterone receptor (PR)+; 21% were ER-/PR-. Among 8,118 participants with information on HER-2 tumor status, 74.8% were HER-2- and 18.5% were HER-2+. At 1-2 years post-diagnosis (on average), 17.9% of participants were obese (BMI ≥ 30 kg/m2), 32.6% were overweight (BMI 25-29 kg/m2), and 59.9% met the 2008 Physical Activity Guidelines for Americans (≥ 2.5 h per week of moderate activity). During follow-up (mean = 8.4 years), 3,736 deaths (2,614 from breast cancer) and 3,564 recurrences have been documented. After accounting for differences in year of diagnosis and timing of post-diagnosis enrollment, five-year overall survival estimates were similar across cohorts. This pooling project of 18,000 breast cancer survivors enables the evaluation of associations of post-diagnosis lifestyle factors, QOL, and breast cancer outcomes with an adequate sample size for investigation of heterogeneity by hormone receptor status and other clinical predictors. The project sets the stage for international collaborations for the investigation of modifiable predictors for breast cancer outcomes.