Abstract P4-03-07: Analysis of hereditary cancer syndromes by using a panel of genes: Novel and multiple pathogenic mutations

BACKGOUND: Hereditary cancer predisposition syndromes are believed to be responsible for approximately 5-10% of all diagnosed cancer cases. In the past, single genes analysis of certain high risk genes was used for the determination of the genetic cause of cancer heritability in certain families. The selection of genes was mainly based on the family history of the individuals analyzed and included only highly associated genes (e.g. the BRCA1 and BRCA2 genes for families with breast cancer history. Nowadays though, the application of Next Generation Sequencing (NGS) technology has facilitated multigene panel analysis and is widely used in clinical practice, for the identification of individuals with cancer predisposition gene mutations.

AIM: The aim of this study was to investigate the extent and nature of mutations in 36 genes implicated in hereditary cancer predisposition in individuals referred for testing in our lab.

MATERIALS & METHODS: In total, 1197 individuals were referred for testing in our lab in the past four years from Greece, Romania and Turkey. The analysis of genes involved in hereditary cancer predisposition was performed using two NGS approaches. The first 451 individuals were analyzed using an amplicon based sequencing method (26 gene panel), while the following 746 individuals were analyzed using a capture based method (33 gene panel). Genomic DNA was enriched for targeted regions of 36 genes involved in hereditary predisposition to cancer included in both versions of the panel (APC, BMPR1A, BRCA1, BRCA2, CDH1, CDK4, CDKN2A, EPCAM, MEN1, MLH1, MSH2, MSH6, MUTYH, PALB2, PMS2, PTEN, RET, SMAD4, STK11, TP53, VHL, ATM, BRIP1, CHEK2, NBN, RAD51C, RAD51D, BARD1, BLM, CHEK1, ABRAXAS1 (FAM175A), MRE11 (MRE11A), NF1, RAD50, RAD51B, XRCC2). Sequencing was carried out using the Illumina NGS technology. Reads were aligned to the reference sequence (GRCh37), and sequence changes were identified and interpreted in the context of a single clinically relevant transcript. The presence of large genomic rearrangements was investigated by computational analysis of NGS results and the use of MLPA for 13 genes. All clinically significant observations were confirmed by orthogonal technologies.

RESULTS: In total, a pathogenic mutation was identified in 259 of the 1197 individuals (21.6%) analyzed while a VUS was identified in 35.7% of the cases. Clinically significant mutations were identified in 29 of the genes analyzed. Concerning the mutation distribution among individuals with positive findings, 44.7% of them were located in BRCA1/2 genes whereas 20.9%, 19.9%, and 14.5% in high, moderate and low risk genes respectively. In addition to BRCA1 and BRCA2 genes other highly mutated genes were CHEK2 (10.6%), PALB2 (7.1%), MUTYH (7.1%) and ATM (4.3%). Of note is that 25 of the 259 positive individuals (9.7%) carried clinically significant mutations in two different genes and 5.8% had a large genomic rearrangement (LGR).

CONCLUSIONS: Our results support the clinical significance of analysis of a panel of genes involved in hereditary cancer predisposition. In our cohort, analysis of this panel allowed for the identification of 8.3% additional pathogenic variants in moderate/low risk genes, enabling personalized management of these individuals.

Citation Format: Tsoulos N, Tsaousis GN, Papadopoulou E, Agiannitopoulos K, Pepe G, Kambouri S, Apessos A, Diamantopoulos N, Floros T, Iosifidou R, Katopodi O, Koumarianou A, Markopoulos C, Papazisis K, Venizelos V, Xanthakis I, Xepapadakis G, Banu E, Eniu DT, Negru S, Stanculeanu DL, Ungureanu A, Ozmen V, Tansan S, Tekinel M, Yalcin S, Nasioulas G. Analysis of hereditary cancer syndromes by using a panel of genes: Novel and multiple pathogenic mutations [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-03-07.

Abstract P1-06-02: Comparative survival analysis of multiparametric tests in the TEAM pathology study: What to do when molecular tests disagree?

Multiparametric assays for risk are increasingly used in the management of node-negative and node-positive hormone receptor-positive invasive breast cancer. Data from multiple sources suggests different tests may provide different risk estimates at the individual patient level1. Analysis from the TEAM pathology study (Bayani and Yao et al npjBreast Cancer, 2017) allows direct comparison of prognostic information from gene signatures in a clinical trial cohort of postmenopausal patients. Risk classifications using genes comprising the following multi-parametric tests: OncotypeDx® (Genomic Health Inc.)2,3, Prosigna™(NanoString Technologies, Inc.)4-6, Mammaprint® (Agendia Inc.)7,8 were performed. For the OncotypeDX-Like Recurrence Score (RS), RNA abundance was processed to fit the measurement range as described2,3, with classification into high, intermediate or low risk groups based the derived RS and modeled for DRFS. For the Prosigna-Like Risk of Recurrence Score (ROR), samples were processed as previously outlined9, then modelled against DRFS. For the MammaPrint-Like Risk Score, samples were processed by published methods8 and modelled for DRFS. Comparing OncotypeDx-Like with Prosigna-Like showed that 45% of cases were classified identically by both (3.3% low risk, 20.9% intermediate, 20.7% high). Of 3370 cases, 353 (10.5%) had scores differing by more than 1 classification (i.e. hi/low or low/high). Almost all (343) of these were cases classified high risk by OncotypeDX-Like RS/low risk by Prosigna-Like ROR (Table 1). Univariate Cox regression analysis, using low/low cases as a reference (relative risk of distant metastasis =1.0), suggested that cases called low risk by Prosigna-Like ROR/High risk by OncotypeDx-Like RS did not perform differently from cases called low risk by both tests (Table 2). However, all cases called intermediate by one test and high risk by another appeared to be high risk (Table 2). Comparisons between Prosigna-Like ROR and MammaPrint-Like scores showed similar concordance between low/low and high/high (52.5% of cases with concordant results). In Prosigna-Like ROR intermediate risk cases, MammaPrint-Like results divided cases between low and high risk, as predicted. Comparisons between these tests is challenging, and evidence on their discordance in risk stratification presents further dilemmas. Preliminary analysis of TEAM suggests a complex inter-relationship between test results in the same patient cohorts requiring careful evaluation.

Table 1OncotypeDX-Like RSLowInt.HighTotalLow1126163431071Prosigna-Like RORInt.1677046151486High10106697813Total289142616553370

Table 2OncotypeDX-Like RSLowInt.HighLowRef1.26 (0.57-2.79)1.13 (0.49-2.62)Prosigna-Like RORInt.1.2 (0.47-3.05)2.22 (1.03-4.78)4.27 (2.01-9.08)High6.10 (1.58-23.6)4.15 (1.79-9.59)4.92 (2.32-10.42)

Citation Format: Bartlett JMS, Bayani J, Kornaga E, Piper T, Mallon E, Yao CQ, Boutros PC, Hasenburg A, Kieback DG, Markopoulos C, Dirix L, Seynaeve C, Can de Velde CJH, Rea DW. Comparative survival analysis of multiparametric tests in the TEAM pathology study: What to do when molecular tests disagree? [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-06-02.

Abstract P1-06-04: Simplified histological grading of breast carcinoma – potential for improved concordance and consistency in breast cancer grading?

Histological grade remains an independent predictor of outcome for invasive breast cancer. The internationally accepted standard grading system is the Elston and Ellis grading system based on a local hospital (Nottingham) cohort treated between 1951-1973. Histological grade, with nodal status, tumour size and receptor measurements (ER, PgR, HER2) give important information even in the context of current molecular testing for breast cancer. In 2009 we proposed a simplified approach to the EE system based on evidence from another hospital series (Thomas et al Histopathology 2009 DOI 10.1111/j.1365-2559.2009.03429.x). Here we report a second validation of this approach using a large phase III clinical trial cohort the Tamoxifen Exemestane Adjuvant multicentre Trial.

A single pathologist (EM) regraded over 4200 cases using a single H&E slide from the TEAM pathology study. Individual scores (1-3) were provided for tubule formation, nuclear pleomorphism and mitotic count and summed to provide the EE score (3-9) resulting in a final grade of 1, 2 or 3 for each case. As previously reported the Simplified Binary Scoring system (SBS) reorganizes this data such that each component is given a score of 1 or 2 with a sum ranging from 3-6. In the current analysis we compared the impact of this revised grading system on patient outcome.

Of 4264 centrally regraded tumours in the TEAM pathology cohort, EE scores for tubular formation were 1 in 102 cases (2.4%), 2 in 503 cases (11.8%) and 3 in 3659 (85.8%). For nuclear pleomorphism only 2 cases were EE score 1 (0.05%), 3117 were score 2 (73.1%) and 1146 score 3 (26.9%). For Mitotic count 3423 (80.3%) were scored 1, 707 (16.6%) scored 2 and 134 scored 3 using the EE system. As previously observed, most/all EE categories could be captured using a simple binary system (SBS, see Table 1).

Table 1 EE Grade  SBS SCORE12335460043239705068217600618 GG Score  EE GradeLowHigh 13327819.02%21377132248.98%35751790.07% GG Score  SBS SCORELowHigh 33508419.35%4120284741.34%515947474.88%65751289.98%

In a comparison between conventional grading and molecular (using a Genomic-Grade signature) we observed the predicted equal split of EE Grade 2 cases into GG high/versus low. For the SBS score the higher scores were enriched for GG High cases.

We show a novel grading system can provides a potentially simple and more reproducible approach to immunohistochemical grading. Comparisons with molecular grading approaches may suggest improved concordance between novel grading approaches and molecular systems. Further comparisons with outcome and molecular signatures will be presented.

Citation Format: Bartlett JMS, Thomas J, Mallon E, Piper T, Bayani J, Hasenburg A, Kieback DG, Markopoulos C, Dirix L, Seynaeve C, van de Velde CJH, Rea DW. Simplified histological grading of breast carcinoma – potential for improved concordance and consistency in breast cancer grading? [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-06-04.

Abstract P2-09-17: Evaluation of the oncomine comprehensive assay for the identification of actionable mutations for therapeutic stratification from the TEAM pathology cohort

Large-scale sequencing initiatives have revealed a wealth of common and novel variants as well as copy-number aberrations, across different malignancies. This growing list of variants/aberrations can sometimes be matched to specific therapeutics. Such “actionable mutations/changes” hold promise for personalized treatment in the future, with treatments tailored to molecular abnormalities. Presently, women with hormone positive early breast cancer continue to experience improved survival on adjuvant anti-hormone therapy, but a significant number of women continue to progress. Therefore, there is a need to identify those women for whom current therapies are insufficient and to identify alternative therapeutic interventions. We explored the used of genetic profiling using a comprehensive solid tumor next generation sequencing (NGS) assay (the Oncomine Comprehensive Assay, OCA) to characterize early invasive breast cancer. The OCA is based on the Ion Torrent™ NGS platform and Ion AmpliSeq™ library preparation technology, coupled to the Oncomine™ Knowledgebase, for target selection, variant calling, and data annotations. The OCA includes 87 genes for hotspot mutation detection, 48 genes for full length sequencing and 43 genes for focal copy number assessment. The OCA provides a standardized informatics workflow and quality control (QC) parameters to process samples in a translational clinical research setting. To explore the application of the OCA to early invasive breast cancers, we performed a retrospective pilot study in a subset of cases from the TEAM trial. From the TEAM pathology samples, 420 were chosen in a case-control fashion, 413 samples were analyzed, 388 samples passed standard QC metrics, and 254 samples (65%) were found to contain 368 variants with Oncomine Knowledgebase annotations. Briefly, variants of PIK3CA were most frequent at 42.7% (157/368), followed by TP53 at 27.2% (100/368), PTEN at 5.7% (21/368), BRCA2 at 3.8% (14/368), SF3B1 (12/368), AKT1 (11/368) and PTCH1 (11/368) at 3.3%, 3.0%, 3.0%; respectively. Other variants were detected in ATM, ERBB2, RB1, FGFR2, NF1, CDKN2A, PIK3R1 and others. Amongst the 43 genes assessed for copy-number, 23 showed copy-number changes across 132 samples totalling 167 CNVs. 256 samples showed no copy-number alterations in any of the genes on the panel. ERBB2 was most frequently altered at 28.1% (47/167), followed by FGFR1 at 23.4% (39/167), CCND1 at 15.0% (25/167) and MDM2 at 10.2% (17/167). Copy-number losses were identified in TP53, RB1, PTEN, BRCA2 at 0.6% each; as well as CDKN2A at 1.8% (3/167). Analytical validation of a subset of gene variants and copy-number changes will be presented in addition to the evidence of potential future application of the Oncomine Comprehensive Assay to precision oncology goals.

Citation Format: Bayani J, Crozier C, Quintayo MA, Amemiya Y, Zhang X, Larivière M, Sadis S, Smith JM, Hasenburg A, Kieback D, Markopoulos C, Dirix L, Yaffe M, Seth A, Feilotter H, Rea D, Bartlett JMS. Evaluation of the oncomine comprehensive assay for the identification of actionable mutations for therapeutic stratification from the TEAM pathology cohort [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-09-17.

Clinical evidence supporting genomic tests in early breast cancer: Do all genomic tests provide the same information?

Breast cancer (BC) has historically been treated as a single disease entity; however, in the last decade, insights into its molecular heterogeneity have underpinned the development/commercialisation of several genomic tools whose goal is to guide patient management in early BC. These include the Oncotype DX^® Breast Recurrence Score™ assay, MammaPrint^®, Prosigna^®, and EndoPredict^®. Although these assays are similar in that they are all multigene assays reflecting risk of recurrence, they differ substantially in the technological platform used to measure gene expression; the number and identity of genes assessed; the patient populations used for development and validation; and the level of evidence supporting clinical utility. They also differ in the amount of evidence demonstrating their impact on treatment decisions and cost effectiveness in different countries. This review discusses these 4 assays, highlighting the clinical evidence that supports each of them, while focussing on the Recurrence Score assay. This assay has the greatest body of evidence supporting its clinical utility and decision impact/effectiveness, and currently is the only one validated as a predictor of response to adjuvant chemotherapy in hormone-receptor positive early BC patients treated with endocrine therapy and to be included as such in international/national BC treatment guidelines. The review also discusses ongoing prospective trials investigating the 4 assays, recent outcome studies, as well as analyses comparing different assays on the same tumour blocks.

Computer-aided preoperative diagnosis of microcalcifications on mammograms

Purpose: To evaluate of a computer-aided method for differentiating malignant from benign clustered microcalcifications.

Material and Methods: Our material was 350 suspicious microcalcifications on mammograms from 330 female patients who underwent breast biopsy (after hook wire localization and under mammographic guidance). The histologic findings were malignant in 140 cases (40%) and benign in 210 cases (60%). Those clusters were manually detected, computer-aided analyzed and quantitatively estimated. Besides computer analysis, 3 physicians-observers (2 radiologists and 1 breast surgeon) evaluated the malignant or benign nature of the clustered microcalcifications. The performance of the artificial network, each observer and the three observers as a group was evaluated by receiver operating characteristics (ROC) curves.

Results: Comparison of the ROC curves revealed the following AUC values (area under the curve): computer – 0.950, physician 1 – 0.815, physician 2 – 0.830, physician 3 – 0.830, and physicians as a group – 0.825. The results, compared by the student t-test for paired data, showed a statistically significant difference between computer analysis and physicians' performance, independently and as a group.

Conclusion: Our study showed that computer analysis achieved statistically significantly better performance than that of physicians in the classification of malignant and benign calcifications.

Incidence of inactive allele CYP2D6*4 among Greek women suffering from hormone-sensitive breast cancer

BACKGROUND

The incidence of CYP2D6*4 among Caucasians is estimated up to 27%, while it is present in up to 90% of all poor metabolizers within the Caucasian population. The hypothesis under question is whether the presence of one or two non-functioning (null) alleles predicts an inferior outcome in postmenopausal women with breast cancer receiving adjuvant treatment with tamoxifen. The aim of the present study is to estimate the incidence of CYP2D6*4, in the Greek population and more precisely among females suffering from breast cancer.

MATERIALS AND METHODS

Eighty unrelated mainland Greek female volunteers suffering from hormone-sensitive breast cancer were recruited during their primary handling or follow-up examination in order to provide samples for purification and polymerase chain reaction/restriction fragment length polymorphism (PCR-RFLP) of genomic DNA derived from buccal swabs.

RESULTS

The incidence of individuals with at least one present allele*4 within the Hellenic population was estimated to be as high as 30% (n = 24/80), with a 95% confidence interval of 20% to 40%. From the statistical point of view, it can be securely stated that incidence of *4 among Greek women is over 20%. The incidence of homozygous carriers of *4 in the present sample occurred in 8.75%, while the incidence of allele*4 haplo-type occurred in 19.4% (n=160).

CONCLUSION

Although the outcoming results for Greek women are actually in line with existing data for other European nations, it should be noted, that a routine CYP2D6 testing of women suffering from breast cancer is formally not recommended, as the clinical significance of CYP2D6 phenotype in treatment and outcome of breast cancer remains unclear.

Abstract P2-08-29: Defining a signature of residual risk following endocrine treatment in the tamoxifen and exemestane adjuvant multinational (TEAM) trial

Introduction: There are a number of commercially-available tests to stratify risk for women diagnosed with early breast cancer. While such "Generation I" tests are increasingly being used, a consensus is growing that these tests are moderately accurate in assessing risk. Moreover, Generation I tests fail to direct more personalized treatment. Therefore, there is a clear need for more informative "Generation II" tests that better assess risk, also on the long term, and provide theranostic targets. To this end, we have performed an mRNA abundance-based analysis trained in the 790 patients of the UK TEAM cohort to identify a signature of residual risk , to be validated in the remaining 3000 patients from the TEAM pathology study.

Methods: RNA extracted from the tumors of respective TEAM pathology study patients were profiled using a 165-gene NanoString code set. The gene list was compiled from targets that comprise many of the existing risk assessment tests, in addition to genes known to be of importance for breast cancer pathogenesis. Signal intensities were normalized using the R statistical environment; 336 different combinations of preprocessing methods were assessed and the most optimal method selected using unbiased criteria. A10-fold cross-validation approach, in combination with a network-based patient risk score calculation formula, was used to derive a 95-gene signature. Briefly, genes were first filtered based on a Cox regression p-value threshold of 0.25; the sum of the weighted mRNA abundance levels of the result genes was calculated for each patient as the risk score. Patient-wise risk scores were then used in a multivariate Cox proportional hazards model along with clinical covariates such as age, grade, HER2 status and nodal status, using DRFS truncated to 10 years as an end-point.

Results: Univariate survival analysis revealed a number of significantly prognostic candidates. The resulting 95-gene signature identified in the training set, stratified patients into high and low risk with an HRhigh of 2.74 (p<2.06 x10-4) when adjusted for age, grade, HER2 status and nodal status; resulting in an AUC of 0.73. Modular analyses of the genes comprising the 95-gene signature identified pathways associated with receptor tyrosine kinase signalling, regulation of cell cycle, and the spindle assembly checkpoint. Additionally, the composition of the gene-list made it possible to characterize the patients into their intrinsic subtypes and to determine their relative risk for recurrence relative to assessment tools available today . The validation of the 95-gene signature will be conducted in the remaining samples in the TEAM pathology study using the bioinformatics strategy described above.

Conclusions: The impact of test-guided therapy using multi-parametric tests is increasingly being felt in the clinic, and is reshaping modern health-care economics. A successful Generation II multi-parametric test will better discriminate those that are truly at high risk for recurrence following endocrine therapy and indicate potential therapeutic options for intervention for those who would not benefit from current modalities.

Citation Format: Bayani J, Yao CQ, Quintayo MA, Haider S, Brookes CL, Yan F, van de Velde CJH, Hasenburg A, Kieback DG, Markopoulos C, Dirix L, Seynaeve C, Boutros PC, Rea DW, Bartlett JMS. Defining a signature of residual risk following endocrine treatment in the tamoxifen and exemestane adjuvant multinational (TEAM) trial. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-08-29.

Adjuvant bisphosphonates in early breast cancer: consensus guidance for clinical practice from a European Panel

Bisphosphonates have been studied in randomised trials in early breast cancer to investigate their ability to prevent cancer treatment-induced bone loss (CTIBL) and reduce the risk of disease recurrence and metastasis. Treatment benefits have been reported but bisphosphonates do not currently have regulatory approval for either of these potential indications. This consensus paper provides a review of the evidence and offers guidance to breast cancer clinicians on the use of bisphosphonates in early breast cancer. Using the nominal group methodology for consensus, a systematic review of the literature was augmented by a workshop held in October 2014 for breast cancer and bone specialists to present and debate the available pre-clinical and clinical evidence for the use of adjuvant bisphosphonates. This was followed by a questionnaire to all members of the writing committee to identify areas of consensus. The panel recommended that bisphosphonates should be considered as part of routine clinical practice for the prevention of CTIBL in all patients with a T score of <-2.0 or ≥2 clinical risk factors for fracture. Compelling evidence from a meta-analysis of trial data of >18,000 patients supports clinically significant benefits of bisphosphonates on the development of bone metastases and breast cancer mortality in post-menopausal women or those receiving ovarian suppression therapy. Therefore, the panel recommends that bisphosphonates (either intravenous zoledronic acid or oral clodronate) are considered as part of the adjuvant breast cancer treatment in this population and the potential benefits and risks discussed with relevant patients.

Biorelevant media for transport experiments in the Caco-2 model to evaluate drug absorption in the fasted and the fed state and their usefulness

In this work we developed and characterized transport media that simulate the composition of micellar phase of intestinal fluids in the fasted and, especially, in the fed state and are appropriate for evaluating intestinal drug permeability characteristics using the Caco-2 model (FaSSIF-TM(Caco) and FeSSIF-TM(Caco), respectively). Media composition was based on FaSSIF-V2 and FeSSIF-V2 and recently reported data on total lipid concentrations in the micellar phase of contents of the upper small intestine in the fasted and the fed state and was adapted for cell culture compatibility. Permeation data were evaluated by compartmental kinetic modeling. Permeability coefficients, P, of hydrophilic drugs were not affected by media composition. In contrast, P values of a series of lipophilic compounds measured with FaSSIF-TM(Caco) and FeSSIF-TM(Caco), and reflecting transport by diffusion were smaller than those obtained with a purely aqueous reference transport medium, aq-TM(Caco), following the rank order aq-TM(Caco)>FaSSIF-TM(Caco)>FeSSIF-TM(Caco). The decline of permeability values was stronger as lipophilicity of the compounds increased. Compared with values estimated using aq-TM(Caco), permeability was reduced, depending on the compound, by more than 20- to 100-fold when measured with FeSSIF-TM(Caco) whereas compound ranking in regard to the permeability characteristics was also affected. The impact of reduced P value on flux through the mucosa, hence on drug absorption, in combination with the drug amount loaded on colloidal particles needs to be taken into consideration in PBPK modeling especially when the food effect is evaluated.

Do type 1 receptor tyrosine kinases inform treatment choice? A prospectively planned analysis of the TEAM trial

BACKGROUND

Epidermal growth factor receptors contribute to breast cancer relapse during endocrine therapy. Substitution of aromatase inhibitors (AIs) may improve outcomes in HER-positive cancers.

METHODS

Tissue microarrays were constructed. Quantitative analysis of HER1, HER2, and HER3 was performed. Data were analysed relative to disease-free survival and treatment using outcomes at 2.75 and 6.5 years.

RESULTS

Among 4541 eligible samples, 4225 (93%) had complete HER1-3 data. Overall, 5% were HER1-positive, 13% HER2-positive, and 21% HER3-positive; 32% (n=1351) overexpressed at least one HER receptor. In the HER1-3-negative subgroup, the hazard ratio (HR) for upfront exemestane vs tamoxifen at 2.75 years was 0.67 (95% confidence interval (CI), 0.52-0.87), in the HER1-3-positive subgroup, the HR was 1.15 (95% CI, 0.85-1.56). A prospectively planned treatment-by-marker analysis demonstrated a significant interaction between HER1-3 and treatment at 2.75 years (HR=0.58; 95% CI, 0.39-0.87; P=0.008), as confirmed by multivariate regression analysis adjusting for prognostic factors (HR=0.55; 95% CI, 0.36-0.85; P=0.005). This effect was time dependent.

CONCLUSION

In the 2.75 years prior to switching patients initially treated with tamoxifen to exemestane, a significant treatment-by-marker effect exists between AI/tamoxifen treatment and HER1-3 expression, suggesting HER expression could be used to select appropriate endocrine treatment at diagnosis to prevent or delay early relapses.

Full Dose Paclitaxel Plus Vinorelbine as Salvage Chemotherapy in Anthracycline-Resistant Advanced Breast Cancer: A Phase II Study

This phase II trial studied the efficacy and toxicity of full dose paclitaxel plus vinorelbine, as salvage chemotherapy in patients with metastatic breast cancer resistant to anthracyclines. Patients received vinorelbine (30 mg/m2) followed 1 hour later by full dose paclitaxel (175 mg/m2) every 3 weeks for a maximum of 8 cycles or until disease progression. Because of the heavy pretreatment of the patients, prophylactic granulocyte-colony stimulating factor (5 microg/kg) was administered daily for 5-10 days. To minimize potentially cumulative neurotoxicity due to both agents, amifostine was given prior to chemotherapy. Thirty-four patients: 8 with tumors primary resistant and 26 with tumors recurring within 3-6 months after anthracycline treatment, were evaluable for efficacy and toxicity. Objective responses occurred in 11 patients [32%; 95% confidence interval (CI): 16.3-47.7%), all partial responses. Responses were observed in lung and liver. The median response duration was 4 months (range 3-7), median time to progression was 5 months (range 3-9) and median overall survival was 8 months (range 4-24). Neutropenia was dose limiting (35% grade 3-4 toxicity). The left ventricular ejection fraction, measured and followed in 18 patients, fell less than 20% below baseline level in 9 patients (50%), but only one patient developed congestive cardiac failure. The paclitaxel-vinorelbine regimen was moderately tolerated and moderately effective in poor prognosis breast cancer patients with visceral metastases and tumors resistant to anthracyclines. The combination at these doses and schedules should be considered in the design of regimens for advanced breast cancer.

Abstract S1-5: PIK3CA mutations are linked to PgR expression: a Tamoxifen Exemestane Adjuvant Multinational (TEAM) pathology study

Background: PIK3CA is mutated in about 26% of breast cancers (BC) and is the most frequently mutated gene in (BC). Almost 95% of mutations occur in exons 9 (E9) or 20 (E20). PIK3CA mutations may be associated with increased survival in endocrine-treated patients; however the impact of mutations in E9 vs E20 is not clear. We assessed 10 common PIK3CA mutations (95% of all mutations), in ER-positive (+ve) samples from the TEAM pathology study (n = ∼4500), and determined the impact of PIK3CA mutations on survival. We report an interim analysis of 1969 TEAM cases.

Methods: DNA was extracted from formalin-fixed paraffin embedded sections. Mutational analyses were performed on 25 mutations in 6 genes (PIK3CAx10, Akt1x1, KRASx5, HRASx3, NRASx2 & BRAFx4), using Sequenom MassArray.

Results: Mutations were found in PIK3CA: 37.5%; Akt1: 3.3%; KRAS: 0.3%; and BRAF: 0.1% of cases. No mutations were found in HRAS or NRAS (n = 1969). 90% of PIK3CA mutations were located in E9 and E20. Outcome data was available for 1958/1969 patients. Patients whose tumours contained any PIK3CA mutations (n = 739) were at lower risk of distant metastasis, Hazard ratio=0.86 (0.67–1.11), when compared to those without PIK3CA mutations (n = 1219); although this difference was not statistically significant (Cox Regression; p = 0.24). PIK3CA mutations were significantly more frequent in HER2-negative (−ve) (39%) than in HER2+ve samples (25%) (p = 0.001), without evidence that PIK3CA mutations differentially impacted outcome in HER2+ve vs HER2-ve patients. A positive correlation was demonstrated between PIK3CA mutations and PgR Allred score (p = 0.002) but not ER Allred score (p = 0.37). With increasing PgR Allred score increase there is an increased frequency of mutations in E20 but not E9 (Table 1).

Discussion: This study indicates a higher percentage of PIK3CA mutations in ER+ve BC samples than previously demonstrated, either for BC as a whole or for ER+ve cases, suggesting that in ER+ve early BC, PIK3CA mutations are more common than previously reported.

Furthermore, increased PIK3CA mutation frequency is significantly associated with increasing PgR Allred score and this appears solely due to increased numbers of patients with E20 mutations further complicating the analysis of the impact of PIK3CA mutations in BC. This may explain current uncertainty regarding the impact of PIK3CA mutations in E9 vs E20 with respect to clinical outcome. Whilst we were unable to show a significant impact on outcome in patients whose tumours contained PIK3CA mutations, we believe the complex relationship between PgR expression (good prognosis indicator) and PI3K mutations requires further exploration in the full dataset using interaction techniques adjusting for the impact of PgR on outcome.

Mutational analysis and correlation with clinical outcome data for the remaining ∼2500 DNA samples, along with the existing data for 1969 patients, will be presented.

P5-16-02: The Impact of Educational Materials on Compliance and Persistence with Adjuvant Aromatase Inhibitors: 2 Year Follow-Up and Final Results from the CARIATIDE Study

Rationale Understanding and effectively addressing the factors that affect patient compliance with adjuvant aromatase inhibitors (AI) is required in order for patients to obtain maximum benefit from treatment. The CARIATIDE study sought to determine whether the provision of educational materials (EM) could improve compliance and persistence with adjuvant AI. At 1-y follow-up (FU), there was no improvement in overall compliance with AI therapy, compliance with initial AI or persistence rates when EM were provided. Final results from the 2-y FU are presented here.

Methods This 2-y, global observational study (NCT00681122) randomized 2758 patients, across 18 countries, to Group A: Standard Therapy or Group B: Standard Therapy + EM. The EM were developed in collaboration with patient advocates, and consisted of a range of information on breast cancer-related topics. Compliance rate with adjuvant AI medication was the primary endpoint. Secondary endpoints included persistence rate after 1 and 2y, and reasons for, and time to, discontinuation of AI therapy. Compliance rate was defined as the proportion of patients being ‘compliant’ with the adjuvant AI medication; switching from AI therapy to tamoxifen would result in a non-compliance score at time of switching. For compliance with initial adjuvant AI medication, switching to another AI or hormone therapy would result in a non-compliance score. A patient was considered a ‘persistent’ user if they did not switch AI medication, AI medication was uninterrupted and there was no discontinuation of the AI medication during the second year. Patients’ compliance and behavior were evaluated using compliance questionnaires, EM feedback and validated questionnaires (EORTC IN-PATSAT32, GHQ-12, FACT-ES).

Results Of the 2758 patients randomized at study initiation, 2242 were available for analysis at 2-y FU. The results confirmed those obtained at 1-y FU. No statistically significant difference in compliance with AI therapy was observed between Group A and Group B (82% and 82%, respectively, p=0.9926). Compliance with initial AI was 81% in Group A and 80% in Group B (p=0.5541), with persistence rates of 90% and 88%, respectively (p=0.2425). Of the proportion of patients who had compliance data for both years (Group A n=1118; Group B n=1111) 72% were compliant for the whole 2-y FU period. Across the full 2-y FU, AI treatment discontinuation rates of 8% and 9% were observed in Group A and B, respectively, with discontinuation most frequently attributed to AI-related side effects. Analysis showed that no specific baseline demographic characteristics were associated with compliance behavior. Compliance rates differed widely between countries.

Conclusions At 2-y FU, EM were not found to improve overall patient compliance, compliance with initial AI, or persistence with therapy. In total, 72% of patients were compliant across the full 2-y FU. AI-related side effects remained the most frequent cause of AI treatment discontinuation across the full FU period. The 2-y CARIATIDE data confirm the 1-y findings.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-16-02.

Abstract P1-10-03: CARIATIDE: The Impact of Educational Materials and Demographic Characteristics on Compliance with Adjuvant Aromatase Inhibitor Treatment

Background

Long-term use of adjuvant aromatase inhibitors (AI) can be associated with patient non-compliance, but the factors that impact this are currently unclear. A comprehensive understanding of the reasons behind non-compliance is important to inform the design of future interventions intending to improve patient compliance. Educational materials (EM) may improve patients’ treatment compliance, as may demographic characteristics such as country, post-operative chemotherapy, age and BMI. Methods

This 2 year, global observational study (NCT00681122) was designed to investigate whether EM could influence patients’ motivation and behavior, and improve treatment compliance with adjuvant AI treatment. Across 18 countries, 2758 patients were randomized 1:1 to Group A: Standard Therapy or Group B: Standard Therapy + EM. EM received by Group B consisted of a range of information on breast cancer related topics. The primary endpoint was compliance rate for the adjuvant AI medication. Secondary endpoints included persistence rate after 1 and 2 years, and reasons for and time to treatment discontinuation of AI. Compliance rate was defined as proportion of subjects being ‘compliant’ with regard to the adjuvant AI medication; switching from AI to tamoxifen would result in a non-compliance score at time of switching. For compliance to initial adjuvant AI medication, switching to another AI or hormone therapy would result in a non-compliance score. A subject was considered a ‘persistent’ user if, during the first year, they did not switch AI medication, AI medication was uninterrupted or there was no discontinuation of the AI medication. Patients’ compliance and behavior were assessed using validated questionnaires (EORTC-INPATSAT-32, GHQ-12, FACT-ES), specifically developed OPTIMA-X, compliance questionnaire and EM feedback in Group B. Results

Analysis of 1 year data did not demonstrate statistically significant differences between compliance rates for Groups A and B. Overall compliance was 81% and 82% for Groups A and B, respectively. Compliance with initial AI was reported as 75% for Group A and 77% for Group B, with persistence rates of 84% and 86%, respectively. EM only significantly improved overall compliance in Sweden/Finland (85% and 100%, Groups A and B respectively, p=0.0264, data combined). Demographic sub-group analysis at 1 year gave overall compliance rates of 83% for patients who received post-operative chemotherapy compared with 79% in patients who did not receive post-operative chemotherapy (p=0.0163). Age-group specific compliance for Groups A and B was 70% and 82% at &lt;50y, 83% and 81% at 50-60y, 80% and 82% at 60-70y, and 81% and 82% at &gt;70y, respectively. Compliance reported in Groups A and B for specific BMI groups was 79% and 81% at BMI &lt;25; 82% and 83% at BMI 25-35, and 78% and 77% at BMI &gt;35, respectively. Discussion

At 1 year, overall compliance, compliance to initial AI and persistence with therapy was not significantly different between treatment arms. Out of 18 countries, only Sweden/Finland demonstrated a significant improvement in compliance when EM were used. Post-operative chemotherapy was a predictor for patient compliance with AI, but age-group and BMI do not appear to be predictors.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-10-03.

Abstract S2-3: The Impact of Body Mass Index (BMI) on the Efficacy of Adjuvant Endocrine Therapy in Postmenopausal Hormone Sensitive Breast Cancer (BC) Patients; Exploratory Analysis from the TEAM Study

Background: Obesity is associated with an increased risk of breast cancer (BC) recurrence and decreased survival, also in case of adjuvant endocrine therapy. It is still not clear whether the activity of aromatase inhibitors and tamoxifen (T) given as adjuvant therapy is affected by body mass index (BMI), although both drugs are widely prescribed. In this analysis, we explored the outcome of TEAM patients (pts) treated with exemestane (E) versus T (2.75 yrs), and with E versus T followed by E (T/E) (5 yrs) in relation to BMI.

Patients and Methods: The TEAM trial is a randomized, international phase III study in postmenopausal hormone sensitive early BC pts comparing the activity and safety of adjuvant E (25 mg daily) or the sequence of T (20 mg daily) followed by E (T/E), both regimens given for five years. WHO BMI definitions were used: normal 18.5-24.9 kg/m2, overweight 25-30 kg/m2, obese &gt;30 kg/m2. Disease-free survival (DFS) and overall survival (OS) were calculated by Kaplan-Meier method; results were compared by using the log-rank test and Cox proportional hazard modelling adjusted for country.

Results: Weight and height was known in 4741 pts. Mean BMI was 26.9 kg/m2 (SD 4.9); 39% had a normal BMI, 36.9% overweight, and 23.3% of pts was obese. Underweight pts (n=41, 0.9%) were excluded from further analysis. At 2.75 yrs (E vs T) disease relapse in normal weight, overweight and obese pts using E was observed in 8.1%, 6.8% and 7.5% respectively (p=0.57), and in 9.1%, 8.8%, and 12.5%, respectively (p=0.06) of pts using T. The hazard ratio (HR for risk of relapse on E vs T) in the three subgroups was 0.91 (95%CI 0.66-1.24), 0.78 (95%CI 0.55-1.089), and 0.57 (95%CI 0.39-0.84, p=0.004), respectively. At a median follow-up of 5.1 years, disease relapse in normal weight, overweight and obese pts using E occurred in 14.8%, 15.1% and 15.1%, respectively; and in pts using T in 17.0%, 16.9%, and 18.3%, respectively. Regarding DFS, the HR in normal weight, overweight, and obese pts was 0.87 (95%CI 0.69-1.10), 0.88 (95%CI 0.70-1.11), and 0.75 (95%CI 0.56-1.01, p=0.058), respectively, and with respect to OS 0.87 (95%CI 0.65-1.15, p= 0.32), 0.89 (95%CI 0.67-1.18, p= 0.43), and 0.71 (95% CI 0.51-1.01, p= 0.053), respectively.

Conclusions: After 2.75 years more disease events were observed in obese women using tamoxifen, which was not seen in obese exemestane users, whereas at 5 years these differences in disease recurrences disappeared in this group. In contrast to recent reports, there seems to be a difference regarding the influence of a high BMI on recurrence rate between tamoxifen and the aromatase inhibitor exemestane. Further research on this topic is warranted.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr S2-3.

Abstract P3-10-33: Mammostrat® as an Immunohistochemical Multigene Assay for Prediction of Early Relapse Risk in Postmenopausal Early Breast Cancer: Preliminary Data of the TEAM Pathology Study

Background: Postmenopausal early breast cancer patients, treated with endocrine therapy, have approximately 90% five year disease free survival (DFS). However, for patients at higher risk of relapse, additional adjuvant chemotherapy may be indicated. The challenge is to prospectively identify such patients. The Mammostrat test uses five immunohistochemical markers to stratify patients on tamoxifen (T) therapy into various risk groups potentially guiding treatment choices. We tested the efficacy of this panel in the TEAM trial (exemestane (E) versus T→E) to determine the relevance in patients treated with an AI.

Patients & Methods: Pathology blocks from 4598 TEAM patients were collected and tissue microarrays constructed. The cohort overall was 47% node positive, and 36% also received adjuvant chemotherapy. Samples were stained, using triplicate 0.6mm2 TMA cores, and positivity for p53, HTF9C, CEACAM5, NDRG1, SLC7A5 assessed. Each case was assigned a Mammostrat risk score and analysed for disease free survival (DFS) by marker positivity and risk score.

Results: Preliminary results on the UK TEAM cohort (1059 cases) showed 18.9% stained positive for p53 (184/972), 21.3% for NRDG1 (204/956), 26.4% for SLC7A (253/957), 21.9% for HTF9C (220/1004), 18.3% for CEACAM5 (185/1009). Complete data was available for 919 cases including patients treated with chemotherapy, with 447 (49%) designated low risk, 213 (23%) medium and 259 (28%) high risk. In univariate analysis, Mammostrat scores were prognostic (p=0.02), with 5 year DFS (see comment above) results being 86.9±1.7%, 80.1±3.0% and 80.8±2.6% for patients with low, medium and high Mammostrat scores respectively. Analyses on the entire TEAM pathology cohort are ongoing, and further data with sufficient power to evaluate the impact of Mammostrat in multivariate regression analyses will be presented. Conclusion: Preliminary analysis of the impact of the Mammostrat score in both tamoxifen and exemestane treated patients suggests it retains its prognostic value in this context. Further analysis with the power to evaluate the impact of Mammostrat in multivariate regression analyses will be presented.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-10-33.

Abstract PD10-03: Is 5-50% of Amplified Cells a Suitable Cut Off To Define Heterogeneous Amplification of the HER2 Oncogene?

Background: A recent panel guideline, published on behalf of the College of American Pathologists, redefines heterogeneous amplification of HER2 as the presence of between 5-50% of cells with a HER2/CEP17 ratio ≥2.20[Vance et al., 2009]. We are unaware of pre-existing data auditing either the frequency of cells with this ratio in FISH analysis or of the clinical impact of this definition. Without such data it is difficult for clinicians to interpret the reporting of a breast cancer with 5% HER2 amplified in the context of therapeutic decision making.

Patients & Methods: An audit of FISH results from the Birmingham Heartlands Hospital (BHH) routine pathology laboratory was combined with data from analysis of the TEAM pathology study (TPS). All case reports were scanned and the percentage of amplified cells was reported in all cases with at least 20 cells scored as per UK guidelines. Interim data on 1050 cases from Birmingham & 1870 cases from the TEAM trial are reported and the impact of “heterogeneous amplification” on outcome will be presented at the meeting.

Results: Cohort 1: BHH: Of 1050 eligible cases 187 (17.8%) were amplified as defined by UK guidelines (HER2/CEP17 ratio ≥2.00). Of these 32 would be defined as “borderline” by the ASCO/CAP guidelines. All cases were referred due to equivocal IHC results (2+ etc). 147 cases exhibited ≥50% of cells with ratios &gt;2.20 “amplified” under the CAP panel guidelines; 51/147 exhibited at least 30% of “non-amplified” cells (ratio &lt;2.20). A further 381 cases (36.2%) exhibited between 5-50% of cells 5-50% of cells with a HER2/CEP17 ratio of greater than 2.20 and would under new CAP guidelines be regarded as exhibiting “Heterogeneous amplification”.

Cohort 2 TPS: Of 1870 eligible cases, 220 (11.2%) were amplified for HER2 as defined using conventional parameters of HER2/CEP17 ratios above 2.0(as per UK guidelines). Of these 16 cases would be defined as “borderline” by ASCO/CAP guidelines. All cases were ER+ve accounting for the lower frequency of HER2 amplification. 180 cases (9.6%) exhibited ≥50% of cells with ratios above 2.20 satisfying the new CAP guidelines for amplification (non-heterogeneous). Of these 72 (40%) exhibited at least 30% of cells with ratios &lt;2.20.

Conclusion: Using the new CAP panel guidelines for HER2 “heterogeneous amplification” in an audit of 2920 cases identified 955 (32.7%) of heterogeneous amplification, and raised the frequency of “HER2 amplification/heterogeneous amplification” to 44% of cases evaluated. Heterogeneous amplification of the HER2 oncogene is a real and challenging diagnostic finding Evidence relating to the prognostic impact and in particular response to HER2 therapies is currently lacking for these cases. Guidelines should reflect this and seek to gather such evidence before implementing changes to diagnostic practice.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr PD10-03.

Abstract P3-10-04: An Integration of Biological and Pathological Marker Panel in the TEAM Pathology Sub-Study: The Impact of Different Parameters on Risk Estimation of Relapse at Both 2.75 and 5 Years

Background: Recent evidence confirms the importance of both biological and pathological risk markers in predicting early relapse for breast cancer patients treated with endocrine therapy. Most studies use a two step process integrating biological markers into a “biological predictor (e.g. Oncotype Dx, “IHC4” etc) followed by assessment of the predictive value of such tests in the context of pathological markers (grade, nodal status etc). We have taken a one step process integrating both biological and pathological markers into a single model to assess key factors for predicting outcome at 2.75 years and 5 years of endocrine therapy; to inform choices between switching, upfront and extended adjuvant treatment with AIs. Patients & Methods: Pathology blocks from 4598 TEAM patients were collected and tissue microarrays constructed. Quantitative analysis ER, PgR, Ki67, HER1, HER2, and HER3 was performed centrally. A prognostic model, integrating data from biological and pathological markers was created to assess risk (disease-free survival) after 2.75 and 5 years of follow up in the TEAM trial.

Results: Of 4595 eligible cases samples received, 16 were excluded, and 3993 had complete biomarker data for all markers for the final biomarker analysis. In univariate analysis nodal status, grade, size, age at diagnosis, HER1, HER2, PgR, ER and Ki67 were all prognostic. At 2.75 years nodal status, age, PgR histoscore, size, grade, HER2, ER histoscore and HER1 positivity were significant prognostic variables (ranked by WaldX2 statistic), Ki67 and HER3 were not included in this model. At 5 years median follow up; age, nodal status, size, PgR histoscore, grade, Ki67, HER2, and HER1 positivity were significant prognostic variables (ranked by WaldX2 statistic), ER and HER3 were not included in this model. Conclusion: Combined biological and pathological marker panels are of significant value in predicting early relapse in breast cancer patients treated with endocrine therapy, however duration of follow-up may impact on the inclusion of variables in the model. This provides significant information relevant to the choice of different adjuvant endocrine therapies.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-10-04.

Abstract PD08-03: Competing Causes of Mortality vs. Breast Cancer Mortality at 5-Years among 9766 Postmenopausal Women with Hormone Receptor Positive Early Breast Cancer Treated on the TEAM Study of Adjuvant Hormonal Therapy

Background: The TEAM (Tamoxifen Exemestane Adjuvant Multinational) trial is a contemporary multinational study of the effects of 5 years of adjuvant hormonal therapy, either exemestane (E) or tamoxifen switching to E (TàE). Five-year results were presented at SABCS 2009 showing no difference in outcome between E vs TàE (Rea D, SABCS Abstract 11), thus giving us the opportunity to analyze the causes of mortality in the entire population of 9766 women.

Methods: Postmenopausal women with hormone receptor positive (HR+) early breast cancer (BC) were randomized to E or TàE for 5 years after completion of surgery, adjuvant chemotherapy (when indicated), and radiation therapy based on local guidelines. All data were collected and analyzed at the Central Data Center in Leiden. The primary outcome of DFS as well as safety and other secondary outcomes were analyzed in 2009 after 1285 events had occurred to trigger the analysis. Results: Between 2001 and January 2006, 9766 women were randomized; 100% were HR+, 50% had node negative disease, 68% received adjuvant radiotherapy, and 36% received adjuvant chemotherapy. The median follow-up was 5.1 years with over 60% of women having been followed for 5 or more years. Among 961 deaths, 568 (59%) were caused by BC and 393 (41%) by causes other than BC. The cumulative incidence of death from BC vs. other causes at 5-years for all women and by nodal status is as follows (see table):

There was a general relationship with non-breast cancer deaths and increasing age at diagnosis (≥70 years), as expected. Non-breast cancer causes of mortality included second malignancy (105); cardiac (71), cerebral (33), or pulmonary (28) events; miscellaneous other causes (105); and unknown (51).

Conclusions: Among 9766 postmenopausal women with HR+ BC treated with contemporary hormonal strategies following standard primary treatment, the probability of death from causes other than BC was nearly as high as the probability of dying from BC.

Abstract P4-08-02: A Comparison between AQUA Quantitative Fluorescent Immunohistochemistry and Conventional Immunohistochemistry for Hormone Receptors

Background: We have previous data showing that quantitation of hormone receptors can be highly informative in determining risk of early relapse in ER positive early breast cancer treated with tamoxifen or exemestane. Both quantitative immunohistochemistry (QIHC) and flouresecent immunohistochemistry (F-IHC as measured by AQUA technology) are highly prognostic over a wide expression range. We have explored the results of both assays to determine if current assays provide maximum information using current approaches.

Patients &

Methods: Pathology blocks from 4598 TEAM patients were collected and tissue microarrays constructed. Quantitative AQUA and IHC analysis (using image quantitation) of ER and PgR was performed centrally (Edinburgh & HistoRx). Results from both assays were compared and their prognostic impact on DFS at 2.75 years examined.

Results: Both AQUA and QIHC demonstrated linear relationships between intensity of staining for either ER or PgR and DFS at 2.75 years. For both PgR and ER AQUA provided significantly greater prognostic information that QIHC. However AQUA staining explained only 29% and 68% of the variability in ER and PgR QIHC results by logistic regression. Using both AQUA and QIHC data in a forward stepwise selection survival model demonstrated that AQUA and QIHC provided similar prognostic information over 70% and 50% of the range for ER and PgR respectively. High ER QIHC and low ER AQUA scores, and low PgR IHC and high PgR AQUA scores provided prognostic information unique to either platform.

Conclusion: Both QIHC and AQUA analysis of HR expression provides significant and highly important information on DFS risk in early breast cancer. It appears that these two platforms provide overlapping prognostic information and that the range of ER and PgR expression which impacts patient outcome is wider than measured by either system alone. Further investigation of the clinical significance of this broader range of hormone receptor expression in treatment decisions is warranted.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-08-02.

Variations in locoregional therapy in postmenopausal patients with early breast cancer treated in different countries

Background

The Tamoxifen and Exemestane Adjuvant Multinational (TEAM) trial is an international randomized trial evaluating the efficacy and safety of exemestane, alone or following tamoxifen. The large number of patients already recruited offered the opportunity to explore locoregional treatment practices between countries.

Methods

Patients were enrolled in Belgium, France, Germany, Greece, Ireland, Japan, the Netherlands, the UK and the USA. The core protocol had minor differences in eligibility criteria between countries, reflecting variations in national guidelines and practice regarding adjuvant endocrine therapy.

Results

Between 2001 and 2006, 9779 patients of mean(s.d.) age 64(9) years were randomized. Some 58·4 per cent had T1 tumours (range between countries 36·8–75·9 per cent; P &lt; 0·001) and 47·3 per cent were axillary node positive (range 25·9–84·6 per cent; P &lt; 0·001). Independent factors for type of breast surgery were country, age, tumour status and calendar year of surgery. After breast-conserving surgery, radiotherapy was given to 93·2 per cent of patients, 86·0 per cent in the USA and 100 per cent in France. Axillary lymph node dissection was performed in 82·0 (range 74·6–99·1) per cent.

Conclusion

Despite international consensus guidelines, wide global variations were observed in treatment practices of early breast cancer. There should be further efforts to optimize locoregional treatment for breast cancer worldwide.

The TEAM Trial Pathology Study Identifies Potential Prognostic and Predictive Biomarker Models for Postmenopausal Patients Treated with Endocrine Therapy

Background: The Tamoxifen and Exemestane Adjuvant Multinational (TEAM) trial included prospectively planned biomarker studies to identify prognostic and predictive biomarkers for patients receiving endocrine therapy. Quantitative IHC data for ER/PgR (Can Res 69:83S, SABCS2008), HER2, HER3 and Ki67 was available for the current analysis relative to outcome of estrogen receptor–positive (ER+) early postmenopausal breast cancer (BC) patients treated with exemestane versus tamoxifen.Patients & Methods: Pathology blocks from 4598 TEAM patients were collected and tissue microarrays constructed. Quantitative analysis of hormone receptors (HER2/3) by conventional IHC, and image analysis derived continuous scores for Ki67/ER/PgR were analyzed relative to disease-free survival and treatment on an intent to treat basis using survival data for the first 2.75 years of the TEAM trial. Data on HER2FISH and EGF Receptor IHC will be presented.Results: Of 4595 eligible cases samples received, 16 were excluded, 271 had incomplete biomarker data, leaving 4308 patients for the final biomarker analysis. 1275 (30%) cases were HER2/3 positive.A significant treatment by marker effect was observed for exemestane versus tamoxifen with HER2/3 negative cases deriving benefit from aromatase inhibitor treatment (HER2/3-ve HR=0.69 95%CI, 0.53-0.88; HER2/3 pos HR, 1.13; 95%CI, 0.82–1.55; p=0.016 for interaction in multivariate analysis). By conventional and STEPP analysis no predictive effect of Ki67 was observed. In multivariate regression analysis increased HER2 expression (P=0.0001) decreased PgR expression (P&lt;0.0001) and increased percentage of Ki67 positive cells (P=0.004) as continuous IHC variables were independently prognostic as were size (P=0.0001), nodal status (P&lt;0.0001), grade (P=0.03) and age (P&lt;0.0001).Conclusion: Multiple biological parameters (HER2/PgR/Ki67) are independently prognostic in ER+ve early postmenopausal BC. Modelling will be explored to derive prognostic and potentially predictive biomarker signatures for application in BC. Preferential exemestane versus tamoxifen treatment benefit was seen in HER2/3 negative cases, whilst HER2/3 positive cases had a poor prognosis in this population receiving hormonal therapy (suggesting resistance to endocrine therapy), and no evidence of benefit from AIs versus tamoxifen. Type I receptor tyrosine kinases may identify breast cancers with relative resistance to all forms of endocrine therapy. Whilst Ki67 alone was not predictive of benefit from Ais, Ki67, HER2 and PgR were independent prognostic variables and modelling of predictive/prognostic effects may further inform treatment selection in early postmenopausal breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 75.

Management of bone loss in breast cancer patients: 24-month results from the ARBI trial of anastrozole with risedronate

552

Background: The management of bone mineral density (BMD) in postmenopausal, breast cancer (BC) patients (pts) receiveing anastrozole was investigated in this phase III, multicenter, open label trial. Methods: Pretreatment BMD of 217 eligible pts with hormone receptor-positive BC scheduled to receive anastrozole was evaluated at lumbar spine (LS) and hip (HP). Pts with T-score<-2.0 in LS or HP, received anastrozole 1mg/day plus oral risedronate 35 mg/week (A+R) and pts with T-score>-1 in both sites received anastrozole only (A). Pts with T-score<-1 in either site but T-score>-2.0 in both sites were randomized to receive A+R or A alone. All pts received Calcium and Vit D daily. BMD was then assessed at 12 and 24 months. Results: Comparison of randomized arms (A = 33 pts, A+R = 37 pts): T-score change from baseline was significantly different only for LS at 24 months (-0.23 in A vs 0.41 in A+R, Wilcoxon test p = 0.007) and was significantly higher from baseline for the A+R arm (Signed rank test p = 0.01). At 12 months, among A only pts, 4 (12.1%) had a T-score<-2.0 without becoming osteoporotic, while 2(6.1%) moved to the normal BMD region; from A+R pts, only 2(5.4%) had a T-score<-2.0 without becoming osteoporotic, while 9 (24.3%) moved to the normal BMD region. The same trend in BMD changes was also observed at the 24 month evaluation. Group with T-score<-2.0 in either LS or HP (A+R, n = 99): a significant increase for LS both at 12 and 24 months was detected (median increase of T-score by 0.45 and 0.37, p<0.01 for both time points) with a corresponding non-significant change in HP (p = 0.91 and p = 0.15). BMD in 13(13.3%) pts improved to the osteopenic region (-2.0<T-score<-1.0). Group with T-score>-1 in both sites (A, n = 48): significant decrease was detected for HP and LS, both at 12 and 24 months; however, only 11 (22%) pts became osteopenic and 1(2%) became osteoporotic. Conclusions: The addition of oral risedronate in postmenopausal BC patients with osteopenia receiving anastrozole has a favourable effect in BMD at lumbar spine at 24 months.

[Table: see text]

Impact of Breast Cancer Surgery on the Self-Esteem and Sexual Life of Female Patients

Patient satisfaction with cosmetic outcome and the psychological impact of breast cancer surgery were evaluated. A total of 207 patients with primary breast cancer, treated with either breast-conserving surgery ( n = 83), modified radical mastectomy without reconstruction ( n = 108), or mastectomy with delayed breast reconstruction ( n = 16) rated their cosmetic outcome and satisfaction following surgery, and the impact of surgery on their self-esteem and sexual life, by questionnaire. Patients undergoing breast-conserving surgery were most satisfied with their surgery and body image, followed by those treated with mastectomy with delayed reconstruction. Although diagnosis of breast cancer had a negative impact on the psychology of all patients, those undergoing breast-conserving surgery or mastectomy with delayed reconstruction were more satisfied and reported a lower impact on their self-esteem and sexual life versus those who only had mastectomy. Diagnosis of breast cancer has a negative psychological impact on the patient, but the type of surgery has a significant role in post-operative self-esteem and sexual life.