Assessment of HER2 using the 2018 ASCO/CAP guideline update for invasive breast cancer: a critical look at cases classified as HER2 2+ by immunohistochemistry.

In 2018, the American Society of Clinical Oncology/College of American Pathologists revised the criteria for HER2 immunohistochemistry (IHC) equivocal (2+) classification in their updated guideline. We reviewed invasive breast cancer specimens originally classified as equivocal (2+) under the 2018 guideline that underwent HER2 fluorescence in situ hybridization (FISH) testing from August 2018 to August 2019 at our Canadian reference hospital to investigate cases with ambiguous staining patterns between the 1+ and 2+ definitions. Demographics, pathologic features, and pre-analytic conditions were recorded. The H&E and corresponding HER2 IHC slides were reviewed to confirm tumor type and grade, and classify as HER2 indeterminate, 0, 1+, 2+, or "Intermediate" (staining features between the 1+ and 2+ classifications). FISH testing was performed on 289 cases and 273 met inclusion criteria. The FISH-amplified rate was 12.1%. Upon IHC review, 44.7% (122/273) of cases were reclassified as Intermediate. These cases had incomplete staining with moderate intensity (43/122, 35.3%) and/or <10% complete weak or moderate staining (102/122, 83.6%). Intermediate cases had a significantly lower frequency of amplified FISH results than 2+ cases (p < 0.0001), with only four (3.3%) FISH positive and two (1.6%) FISH heterogeneous. Our study highlights the ambiguity in the current guideline for classifying some HER2 IHC patterns. As the rate of gene amplification in these cases was low (4.9%), we recommend adhering to the 2018 HER2 2+ criteria for reflex FISH testing. However, cases with <10% moderate complete staining and certain heterogeneous patterns warrant special consideration. Further descriptive clarification of 1+ criteria is needed.

Nerve growth factor from Indian Russell's viper venom (RVV-NGFa) shows high affinity binding to TrkA receptor expressed in breast cancer cells: Application of fluorescence labeled RVV-NGFa in the clinical diagnosis of breast cancer.

Nerve growth factor (NGF) is a minor and neglected component of snake venom. Present study describes the purification and characterization of a NGF isoform (RVV-NGFa) from Indian Russell's viper venom (RVV). RVV-NGFa showed a protonated molecular ion [MH+] at m/z 17388.725 Da. The RVV-NGFa induced neuritogenesis in PC-12 cells but did not show cytotoxicity in mammalian cells, hemolytic activity, platelet modulation, and interference in blood coagulation system which are the characteristic pharmacological properties of RVV. By ELISA and immunofluorescence microplate reader assay, the RVV-NGFa showed appreciable binding to TrkA receptor expressed in breast cancer MDA-MB-231 and MCF-7 cells; nevertheless, pre-incubation of cells with anti-TrkA (and not TrkB or TrkC) or anti-p75NTR antibody significantly decreased (p < 0.05) this binding. The RVV-NGFa demonstrated insignificant binding with non-cancerous cells (HEK-293, L6) lacking TrkA receptor. The binding of RVV-NGFa to TrkA receptor of breast cancer cells resulted in internalization of ligand (RVV-NGFa)-receptor (TrkA) complex to cell cytoplasm in a time-dependent manner. The spectrofluorometric study demonstrated an interaction between RVV-NGFa and cytosolic domain of the purified TrkA receptor. The fluorescence (FITC)-tagged RVV-NGFa depicted a strong fluorescence signal that was observed under a fluorescence microscope and determined by fluorescence microplate reader assay post binding to breast cancer cells; but no fluorescence signal was detected after incubating FITC-RVV-NGFa with non-cancerous L6 and HEK-293 cells. The clinical application of FITC/fluorescence nanoparticle tagged RVV-NGFa for the ex vivo and in vivo diagnosis of breast cancer is highly promising.

In silico identification of MAPK14-related lncRNAs and assessment of their expression in breast cancer samples.

Mitogen-activated protein kinase (MAP kinase) pathways participate in regulation of several cellular processes involved in breast carcinogenesis. A number of non-coding RNAs including both microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) regulate or being regulated by MAPKs. We performed an in-silico method for identification of MAPKs with high number of interactions with miRNAs and lncRNAs. Bioinformatics approaches revealed that MAPK14 ranked first among MAPKs. Subsequently, we identified miRNAs and lncRNAs that were predicted to be associated with MAPK14. Finally, we selected four lncRNAs with higher predicted scores (NORAD, HCG11, ZNRD1ASP and TTN-AS1) and assessed their expression in 80 breast cancer tissues and their adjacent non-cancerous tissues (ANCTs). Expressions of HCG11 and ZNRD1ASP were lower in tumoral tissues compared with ANCTs (P values < 0.0001). However, expression levels of MAPK14 and NORAD were not significantly different between breast cancer tissues and ANCTs. A significant association was detected between expression of HCG11 and estrogen receptor (ER) status in a way that tumors with up-regulation of this lncRNA were mostly ER negative (P value = 0.04). Expressions of ZNRD1ASP and HCG11 were associated with menopause age and breast feeding duration respectively (P values = 0.02 and 0.04 respectively). There was a trend towards association between ZNRD1ASP expression and patients' age of cancer diagnosis. Finally, we detected a trend toward association between expression of NORAD and history of hormone replacement therapy (P value = 0.06). Expression of MAPK14 was significantly higher in grade 1 tumors compared with grade 2 tumors (P value = 0.02). Consequently, the current study provides evidences for association between lncRNA expressions and reproductive factors or tumor features.

The Impact of Primary Tumor Surgery on Survival in HER2 Positive Stage IV Breast Cancer Patients in the Current Era of Targeted Therapy.

OBJECTIVE: We sought to examine the impact of primary tumor resection on survival in HER2+ stage IV breast cancer patients in the era of HER2 targeted therapy. METHODS: We conducted a retrospective cohort study of women with HER2+ stage IV breast cancer in the National Cancer Database from 2010 to 2012 comparing those who did and did not undergo definitive breast surgery. RESULTS: Of 3231 patients, treatment included primary site surgery in 35.0%; chemo/targeted therapy in 89.4%; endocrine therapy in 37.7%; and radiation in 31.8%. Surgery was associated with Medicare/other government (OR 1.36, 95% CI 1.03-1.81) or private insurance (OR 1.93, 95% CI 1.53-2.42) versus none/Medicaid, radiation (OR 2.10, 95% CI 1.76-2.51), chemo/targeted therapy (OR 1.99, 95% CI 1.47-2.70), and endocrine therapy (OR 1.73, 95% CI 1.40-2.14). Non-Hispanic Black versus White patients (OR 0.68, 95% CI 0.53-0.87) were less likely to have surgery. Overall mortality was associated with insurance (Medicare/other government versus none/Medicaid, HR 0.36, p < 0.0001), receipt of chemo/targeted therapy (HR 0.76, p = 0.008), endocrine therapy (HR 0.70, p = 0.0006), and radiation therapy (HR 1.33, p = 0.0009), NH Black versus White race/ethnicity (HR 1.39, p = 0.002), visceral versus bone-only metastases (HR 1.44, p = 0.0003), and lowest versus highest income quartile (HR 1.36, p = 0.01). Propensity score analysis showed surgery was associated with improved survival versus no surgery (HR 0.56, 95% CI 0.40-0.77). CONCLUSIONS: Surgery of the primary site for metastatic HER2+ breast cancer is associated with improved overall survival in selected patients.

Cost-Effectiveness Analysis of Bevacizumab plus Paclitaxel versus Bevacizumab plus Capecitabine for HER2-Negative Locally Recurrent or Metastatic Breast Cancer.

BACKGROUND: The aim of the current study was to estimate two protocols for HER2-negative locally recurrent or metastatic breast cancer patients, bevacizumab combined with paclitaxel versus bevacizumab combined with capecitabine, from the economic view. METHODS: The process of HER2-negative locally recurrent or metastatic breast cancer treated with bevacizumab combined with paclitaxel or bevaciz-umab combined with capecitabine made up the decision model in our analysis. The primary objective was to show the incremental cost-effectiveness ratio (ICER). The critical parameters and the robustness of the model on the results of the analysis were assessed by univariate sensitivity analysis and probabilistic sensitivity analysis. RESULTS: In the analysis, quality-adjusted life year (QALY) increased by 0.4 with bevacizumab plus paclitaxel compared with bevacizumab plus capecitabine, and incremental cost of USD 4,340.46. Therefore, the ICER was USD 27,252.875. The ICER exceeded the commonly accepted willingness to pay on the recommendation of the World Health Organization, which is defined as 3 times of the gross domestic product per capita of China in the model (USD 25,840.88 per QALY). On univariate analysis, it is found that the most significant affecting factor is the cost of progression-free survival state in the bevacizumab plus paclitaxel group. Besides, bevacizumab plus paclitaxel had a 47.8% probability of being cost-effective versus bevacizu-mab plus capecitabine according to probabilistic sensitivity analysis. CONCLUSIONS: Based on the results of the analysis, bevacizumab plus paclitaxel is unlikely to be a cost-effective option for patients with HER2-negative locally recurrent or metastatic breast cancer compared with bevacizumab plus capecitabine.

Post-marketing assessment of generic tamoxifen in Brazilian breast cancer patients.

Generic formulations of tamoxifen are commonly prescribed to oestrogen receptor-positive breast cancer patients at the Brazilian National Cancer Institute (INCA). We carried out a post-marketing surveillance of the generic tamoxifen formulation in current use at INCA, by comparing plasma concentrations of the parent drug and metabolites obtained with the generic vs the reference formulation. Thirty patients participated in an open-label, bracketed protocol, comprising 3 successive phases of 30-32 days each: the generic formulation was used in phases 1 and 3 and the reference formulation in phase 2. Two blood samples were collected in the last 4 days of each phase, for LC-MS/MS quantification of tamoxifen and metabolites in plasma. The median plasma concentrations (ng/mL) for the reference formulation were as follows: tamoxifen, 135.0 (CI 95% 114.2-155.8); endoxifen, 35.3 (30.0-40.8); and 4-hydroxytamoxifen, 4.8 (4.2-5.4). The endoxifen/tamoxifen plasma concentration ratio was 0.27 (0.21-0.25). ANOVA detected no statistically significant difference in plasma concentrations of tamoxifen, metabolites or the endoxifen/tamoxifen ratio among the three phases. The genetic component (rGC) of the CYP2D6-mediated conversion of tamoxifen into endoxifen, estimated using the repeated drug administration procedure across the three phases, was 0.87, pointing to an important component of genetic variability. In conclusion, this first post-marketing surveillance trial of oncologic generic drugs carried out in Brazilian patients verified the switchability between the reference and the generic tamoxifen formulation currently used at our institution. The adopted bracketed protocol adds confidence to this conclusion and may serve as a frame for future trials of post-marketing assessment of other generic drug products.

Assessment of the efficacy of successive endocrine therapies in hormone receptor-positive and HER2-negative metastatic breast cancer: a real-life multicentre national study.

BACKGROUND: For luminal metastatic breast cancer (MBC), endocrine therapy (ET) is the recommended initial treatment before chemotherapy. Our objective was to evaluate the efficacy of multiple ET lines in a real-life study. METHODS: The Breast Cancer Epidemiological Strategy and Medical Economics (ESME) project analysed data from all patients with systemic treatment for MBC initiated between 2008 and 2014 in one of the 18 French Comprehensive Cancer Centres. The primary end-point was the successive progression-free survival (PFS) evaluation. RESULTS: The ESME research programme included 9921 patients with hormone receptor-positive (HR+)/human epidermal growth factor receptor 2 (HER2) negative (HER2-) MBC. Before any chemotherapy, 4195 (43.4%), 1252 (29.8%) and 279 (6.6%) patients received one, two or three ET ± targeted therapy, respectively. The median PFS for first-, second- and third-line ET ± targeted therapy was 11.5 (95% confidence interval [CI], 10.8-12.1), 5.8 (95% CI, 5.3-6.1) and 5.5 (95% CI, 4.6-6.3) months, respectively. In a multivariate analysis, time from diagnosis to metastatic recurrence (P < 0.0001), presence of symptoms at metastatic relapse (P = 0.01), number of metastatic sites (P = 0.0003) and their localisation (P < 0.0001) were prognostic factors for PFS1. Duration of previous PFS was the only prognostic factor for subsequent PFS (10% threshold). Ten percent of the patients showed long-term response to ET, with a total treatment duration before chemotherapy ≥43.6 months. CONCLUSIONS: Median PFS in our HR+/HER2- real-life cohort is similar to median first-line PFS reported in clinical trials, regardless of ET used as second- and third-line treatment. Despite the international consensus on early initiation of ET, the latter is not prescribed in most of the cases. Patients with a low tumour burden may achieve prolonged response on ET.

Cost-Effectiveness Analysis of Pertuzumab With Trastuzumab and Chemotherapy Compared to Trastuzumab and Chemotherapy in the Adjuvant Treatment of HER2-Positive Breast Cancer in the United States.

OBJECTIVE: The APHINITY trial assessed the effectiveness and the safety of adding pertuzumab to trastuzumab and chemotherapy (THP) compared to trastuzumab and chemotherapy (TH) in the adjuvant management of human epidermal growth factor 2-positive (HER2+) breast cancer. We performed a study to project the potential cost-effectiveness of THP vs. TH. STUDY DESIGN: Trial-based cost-utility modeling analysis. METHODS: We performed an economic evaluation from a payer perspective using a Markov model with six health states: invasive disease-free survival, non-metastatic recurrence, remission, first-line metastatic, subsequent line metastatic, and death. We parameterized the model using data from both arms in APHINITY extrapolated to a patient's lifetime horizon. Estimates of health state utilities were based on EQ-5D trial data and the literature, and costs were estimated from government sources and the published literature. The primary outcomes of the model were life-years (LYs), quality-adjusted LYs (QALYs), costs, and incremental cost-effectiveness ratios (ICERs). Uncertainty was addressed via univariate and probabilistic sensitivity analyses. RESULTS: For the intention-to-treat population, the model projected improved outcomes (by 0.50 LYs and 0.45 QALYs) and increased costs (by $74 420) for ICERs of $147 774/LY gained and $167 185/QALY gained for PHT vs. HT patients. In the node-positive patient population, the model projected improved outcomes (by 0.86 LYs and 0.76 QALYs) and increased costs (by $66 647) for ICERs of $77 684/LY gained and $87 929/QALY gained. For the hormone-receptor-negative patient population, the model projected health gains, increased costs, and ICERs of $147 022/LY gained and $166 518/QALY gained. The results were sensitive to changes in the model time horizon. CONCLUSION: The addition of pertuzumab to the available regimens for HER2+ early breast cancer is likely to be cost-effective for patients in the U.S. at high risk of recurrence.

Assessment of ERBB2/HER2 Status in HER2-Equivocal Breast Cancers by FISH and 2013/2014 ASCO-CAP Guidelines.

Importance: The 2013/2014 American Society of Clinical Oncology and College of American Pathologists (ASCO-CAP) guidelines for HER2 testing by fluorescence in situ hybridization (FISH) designated an "equivocal" category (average HER2 copies per tumor cell ≥4-6 with HER2/CEP17 ratio <2.0) to be resolved as negative or positive by assessments with alternative control probes. Approximately 4% to 12% of all invasive breast cancers are characterized as HER2-equivocal based on FISH. Objective: To evaluate the following hypotheses: (1) genetic loci used as alternative controls are heterozygously deleted in a substantial proportion of breast cancers; (2) use of these loci for assessment of HER2 by FISH leads to false-positive assessments; and (3) these HER2 false-positive breast cancer patients have outcomes that do not differ from clinical outcomes for patients with HER2-negative breast cancer. Design, Setting, and Participants: We retrospectively assessed the use of chromosome 17 p-arm and q-arm alternative control genomic sites (TP53, D17S122, SMS, RARA, TOP2A), as recommended by the 2013/2014 ASCO-CAP guidelines for HER2 testing, in patients whose data were available through Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) and whose tissues were available through the Breast Cancer International Research Group clinical trials. We used data from an international cohort database of invasive breast cancers (1980 participants) and international clinical trial of adjuvant chemotherapy in invasive, node-positive breast cancer patients. Main Outcomes and Measures: The primary objectives were to (1) assess frequency of heterozygous deletions in chromosome 17 genomic sites used as FISH internal controls for evaluation of HER2 status among HER2-equivocal cancers; (2) characterize impact of using deleted sites for determination of HER2-to-internal-control-gene ratios; (3) assess HER2 protein expression in each subgroup; and (4) compare clinical outcomes for each subgroup. Results: Of the 1980 patients in METABRIC,1915 patients were fully evaluated. In addition, 100 HER2-equivocal breast cancers by FISH and 100 comparator FISH-negative breast cancers from the BCIRG-005 trial were analyzed. Heterozygous deletions, particularly in specific p-arm sites, were common in both HER2-amplified and HER2-not-amplified breast cancers. Use of alternative control probes from these regions to assess HER2 by FISH in HER2-equivocal as well as HER2-not-amplified breast cancers resulted in high rates of false-positive ratios (HER2-to-alternative control ratio ≥2.0) owing to heterozygous deletions of control p-arm genomic sites used in ratio denominators. Misclassification of HER2 status was observed not only in breast cancers with ASCO-CAP equivocal status but also in breast cancers with an average of fewer than 4.0 HER2 copies per tumor cell when using alternative control probes. Conclusions and Relevance: The indiscriminate use of alternative control probes to calculate HER2 FISH ratios in HER2-equivocal breast cancers may lead to false-positive interpretations of HER2 status resulting from unrecognized heterozygous deletions in 1 or more of these alternative control genomic sites and incorrect HER2 ratio determinations.

De-Escalation Strategies in Human Epidermal Growth Factor Receptor 2 (HER2)-Positive Early Breast Cancer (BC): Final Analysis of the West German Study Group Adjuvant Dynamic Marker-Adjusted Personalized Therapy Trial Optimizing Risk Assessment and Therapy Response Prediction in Early BC HER2- and Hormone Receptor-Positive Phase II Randomized Trial-Efficacy, Safety, and Predictive Markers for 12 Weeks of Neoadjuvant Trastuzumab Emtansine With or Without Endocrine Therapy (ET) Versus Trastuzumab Plus ET.

Purpose Human epidermal growth factor receptor 2 (HER2)-positive/hormone receptor (HR)-positive breast cancer is a distinct subgroup associated with lower chemotherapy sensitivity and slightly better outcome than HER2-positive/HR-negative disease. Little is known about the efficacy of the combination of endocrine therapy (ET) with trastuzumab or with the potent antibody-cytotoxic, anti-HER2 compound trastuzumab emtansine (T-DM1) with or without ET for this subgroup. The West German Study Group trial, ADAPT (Adjuvant Dynamic Marker-Adjusted Personalized Therapy Trial Optimizing Risk Assessment and Therapy Response Prediction in Early Breast Cancer) compares pathologic complete response (pCR) rates of T-DM1 versus trastuzumab with ET in early HER2-positive/HR-positive breast cancer. Patients and Methods In this prospective, neoadjuvant, phase II trial, 375 patients with early breast cancer with HER2-positive and HR-positive status (n = 463 screened) were randomly assigned to 12 weeks of T-DM1 with or without ET or to trastuzumab with ET. The primary end point was pCR (ypT0/is/ypN0). Early response was assessed in 3-week post-therapeutic core biopsies (proliferation decrease ≥ 30% Ki-67 or cellularity response). Secondary end points included safety and predictive impact of early response on pCR. Adjuvant therapy followed national standards. Results Baseline characteristics were well balanced among the arms. More than 90% of patients completed the therapy per protocol. pCR was observed in 41.0% of patients treated with T-DM1, 41.5% of patients treated with T-DM1 and ET, and 15.1% with trastuzumab and ET ( P < .001). Early responders (67% of patients with assessable response) achieved pCR in 35.7% compared with 19.8% in nonresponders (odds ratio, 2.2; 95% CI, 1.24 to 4.19). T-DM1 was associated with a significantly higher prevalence of grade 1 to 2 toxicities, especially thrombocytopenia, nausea, and elevation of liver enzymes. Overall toxicity was low; seventeen therapy-related severe adverse events (T-DM1 arms v trastuzumab plus ET; 5.3% v 3.1%, respectively) were reported. Conclusion The ADAPT HER2-positive/HR-positive trial demonstrates that neoadjuvant T-DM1 (with or without ET) given for only 12 weeks results in a clinically meaningful pCR rate. Thus, a substantial number of patients are spared the adverse effects of systemic chemotherapy.

Disparities in Use of Human Epidermal Growth Hormone Receptor 2-Targeted Therapy for Early-Stage Breast Cancer.

PURPOSE: Trastuzumab is a key component of adjuvant therapy for stage I to III human epidermal growth factor receptor 2 (HER2)-positive breast cancer. The rates and patterns of trastuzumab use have never been described in a population-based sample. The recent addition of HER2 information to the SEER-Medicare database offers an opportunity to examine patterns of trastuzumab use and to evaluate possible disparities in receipt of trastuzumab. METHODS: We examined a national cohort of Medicare beneficiaries with incident stage I to III HER2-positive breast cancer diagnosed in 2010 and 2011 (n = 1,362). We used insurance claims data to track any use of trastuzumab in the 12 months after diagnosis as well as to identify chemotherapy drugs used in partnership with trastuzumab. We used modified Poisson regression analysis to evaluate the independent effect of race on likelihood of receiving trastuzumab by controlling for clinical need, comorbidity, and community-level socioeconomic status. RESULTS: Overall, 50% of white women and 40% of black women received some trastuzumab therapy. Among women with stage III disease, 74% of whites and 56% of blacks received trastuzumab. After adjustment for tumor characteristics, poverty, and comorbidity, black women were 25% less likely to receive trastuzumab within 1 year of diagnosis than white women (risk ratio, 0.745; 95% CI, 0.60 to 0.93). CONCLUSION: Approxemately one half of patients 65 years of age and older with stage I to III breast cancer do not receive trastuzumab-based therapy, which includes many with locally advanced disease. Significant racial disparities exist in the receipt of this highly effective therapy. Further research that identifies barriers to use and increases uptake of trastuzumab could potentially improve recurrence and survival outcomes in this population, particularly among minority women.

Cost-Effectiveness of Pertuzumab in Human Epidermal Growth Factor Receptor 2-Positive Metastatic Breast Cancer.

PURPOSE: The Clinical Evaluation of Pertuzumab and Trastuzumab (CLEOPATRA) study showed a 15.7-month survival benefit with the addition of pertuzumab to docetaxel and trastuzumab (THP) as first-line treatment for patients with human epidermal growth factor receptor 2 (HER2) -overexpressing metastatic breast cancer. We performed a cost-effectiveness analysis to assess the value of adding pertuzumab. PATIENT AND METHODS: We developed a decision-analytic Markov model to evaluate the cost effectiveness of docetaxel plus trastuzumab (TH) with or without pertuzumab in US patients with metastatic breast cancer. The model followed patients weekly over their remaining lifetimes. Health states included stable disease, progressing disease, hospice, and death. Transition probabilities were based on the CLEOPATRA study. Costs reflected the 2014 Medicare rates. Health state utilities were the same as those used in other recent cost-effectiveness studies of trastuzumab and pertuzumab. Outcomes included health benefits expressed as discounted quality-adjusted life-years (QALYs), costs in US dollars, and cost effectiveness expressed as an incremental cost-effectiveness ratio. One- and multiway deterministic and probabilistic sensitivity analyses explored the effects of specific assumptions. RESULTS: Modeled median survival was 39.4 months for TH and 56.9 months for THP. The addition of pertuzumab resulted in an additional 1.81 life-years gained, or 0.62 QALYs, at a cost of $472,668 per QALY gained. Deterministic sensitivity analysis showed that THP is unlikely to be cost effective even under the most favorable assumptions, and probabilistic sensitivity analysis predicted 0% chance of cost effectiveness at a willingness to pay of $100,000 per QALY gained. CONCLUSION: THP in patients with metastatic HER2-positive breast cancer is unlikely to be cost effective in the United States.

Rapid fluorescence in situ hybridisation (FISH) for HER2 (ERBB2) assessment in breast and gastro-oesophageal cancer.

Evaluation of HER2 (ERBB2) gene amplification or protein expression is standard of care in breast (BR) and advanced stage gastro-oesophageal cancers to identify patients eligible for anti-HER2 therapies. Here, we evaluate a rapid fluorescence in situ hybridisation (FISH) technology (HER2 instant quality (IQ) FISH pharmDx Kit) for detection of HER2 in patients with BR and gastro-oesophageal cancer using 30 FFPE samples that had been previously evaluated with the PathVysion HER2 DNA Probe Kit. Cases were scored as positive (HER2:CEN-17 ≥2.0), negative (HER2:CEN-17 <2.0) or equivocal according to the ASCO/CAP 2013 BR cancer guidelines. Ten samples were positive for HER2 amplification while 20 were negative; none were equivocal. The IQ FISH was able to detect low level amplification (HER2:CEN-17 ratio 2.4). The HER2 IQ FISH pharmDx Kit is a FDA approved kit that offers a rapid turnaround time (approximately 3.5 h) and in our laboratory was 100% concordant with prior PathVysion results.

Updated UK Recommendations for HER2 assessment in breast cancer.

Human epidermal growth factor receptor 2 (HER2) overexpression is present in approximately 15% of early invasive breast cancers, and is an important predictive and prognostic marker. The substantial benefits achieved with anti-HER2 targeted therapies in patients with HER2-positive breast cancer have emphasised the need for accurate assessment of HER2 status. Current data indicate that HER2 test accuracy improved following previous publication of guidelines and the implementation of an external quality assessment scheme with a decline in false-positive and false-negative rates. This paper provides an update of the guidelines for HER2 testing in the UK. The aim is to further improve the analytical validity and clinical utility of HER2 testing by providing guidelines of test performance parameters, and recommendations on the postanalytical interpretation of test results. HER2 status should be determined in all newly diagnosed and recurrent breast cancers. Testing involves immunohistochemistry with >10% complete strong membrane staining defining a positive status. In situ hybridisation, either fluorescent or bright field chromogenic, is used either upfront or in immunohistochemistry borderline cases to detect the presence of HER2 gene amplification. Situations where repeat HER2 testing is advised are outlined and the impact of genetic heterogeneity is discussed. Strict quality control and external quality assurance of validated assays are essential. Testing laboratories should perform ongoing competency assessment and proficiency tests and ensure the reliability and accuracy of the assay. Pathologists, oncologists and surgeons involved in test interpretation and clinical use should adhere to published guidelines and maintain accurate performance and consistent interpretation of test results.

External Quality Assessment (EQA) program for the preanalytical and analytical immunohistochemical determination of HER2 in breast cancer: an experience on a regional scale.

BACKGROUND: An External Quality Assessment (EQA) program was developed to investigate the state of the art of HER2 immunohistochemical determination in breast cancer (BC) in 16 Pathology Departments in the Lazio Region (Italy). This program was implemented through two specific steps to evaluate HER2 staining (step 1) and interpretation (step 2) reproducibility among participants. METHODS: The management activities of this EQA program were assigned to the Coordinating Center (CC), the Revising Centers (RCs) and the Participating Centers (PCs). In step 1, 4 BC sections, selected by RCs, were stained by each PC using their own procedures. In step 2, each PC interpreted HER2 score in 10 BC sections stained by the CC. The concordance pattern was evaluated by using the kappa category-specific statistic and/or the weighted kappa statistic with the corresponding 95% Jackknife confidence interval. RESULTS: In step 1, a substantial/almost perfect agreement was reached between the PCs for scores 0 and 3+ whereas a moderate and fair agreement was observed for scores 1+ and 2+, respectively.In step 2, a fully satisfactory agreement was observed for 6 out of the 16 PCs and a quite satisfactory agreement was obtained for the remaining 10 PCs. CONCLUSIONS: Our findings highlight that in the whole HER2 evaluation process the two intermediate categories, scores 1+ and 2+, are less reproducible than scores 0 and 3+. These findings are relevant in clinical practice where the choice of treatment is based on HER2 positivity, suggesting the need to share evaluation procedures within laboratories and implement educational programs.

Pharmacogenomics variation in drug metabolizing enzymes and transporters in relation to docetaxel toxicity in Lebanese breast cancer patients: paving the way for OMICs in low and middle income countries.

We investigated the association of genetic polymorphisms in drug metabolizing enzymes (DMEs) and transporters in patients with docetaxel-induced febrile neutropenia, by a new high-throughput DMEs and transporters (DMETPlus) microarray platform, characterizing 1936 single nucleotide polymorphisms (SNPs) in 225 genes. We recruited 100 Lebanese breast cancer patients from a consecutive cohort of 277 patients who received docetaxel either alone, or in combination with trastuzumab. Out of 100 patients, 18 had developed febrile neutropenia (cases). They were age- and treatment- matched with 18 patients who did not develop febrile neutropenia on docetaxel (controls). We found that 12 SNPs in seven genes (ABCC6, ABCG1, ABCG2, CYP1A2, CYP2D6, FMO2, and FMO3) were significantly associated with febrile neutropenia after docetaxel treatment. Many of these SNPs have not been previously reported to be associated with toxicity due to docetaxel treatment. Interestingly, one SNP in the FMO3 gene (rs909530) was significantly associated with three clinical endpoints: febrile neutropenia, reduced absolute neutrophil count, and hemoglobin reduction. To the best of our knowledge, this is the first study that evaluated the effect of a large array of nearly 2000 polymorphisms in DMEs and transporters on docetaxel toxicity in breast cancer patients, and in a previously understudied population. Additionally, it attests to the feasibility of genomics research in low- and middle-income countries (LMICs). In light of the current global epidemic of noncommunicable diseases (NCDs) such as breast cancer impacting LMICs, we suggest pharmacogenomics is considered as an integral part of the global health research agenda for NCDs and personalized therapeutics.