Tissue microarray-based study of patients with lymph node-negative breast cancer shows that HER2/neu overexpression is an important predictive marker of poor prognosis

BackgroundDespite good prognosis in most cases of lymph node (LN)-negative breast cancer, individual patients may have markedly different clinical outcomes. Here, we investigated the prognostic significance of HER2/neu overexpression in these tumors.Materials and methodsWe employed a tissue microarray to examine HER2/neu overexpression by immunohistochemical staining in 359 consecutive patients diagnosed with LN-negative breast cancer, who underwent surgery from January 1993 to December 1998.ResultsHER2/neu overexpression was detected in 81 of 359 (23.1%) patients. The 10-year disease-free survival (DFS) values (81.2% versus 61.8%, P value 0.000) and overall survival (OS) rates (85.7% versus 63.9%, P value 0.000) were significantly different between cases with HER2/neu-negative or HER2/neu-positive tumors. After multivariate analysis, HER2/neu status and tumor size were identified as independent prognostic factors for 10-year OS. Moreover, HER2/neu overexpression was significantly associated with poorer clinical outcomes in an intermediate-risk group identified by the St Gallen classification (10-year DFS, 79.6% versus 61.8%, P value 0.000; 10-year OS, 84.7% versus 63.9%, P value 0.000).ConclusionsOur results show that HER2/neu overexpression is an important independent prognostic factor for LN-negative breast cancer cases and support the theory that more intensive adjuvant chemotherapy is required in the population with HER2/neu overexpression.     

High Expression of Class III β-Tubulin Predicts Good Response to Neoadjuvant Taxane and Doxorubicin/Cyclophosphamide-Based Chemotherapy in Estrogen Receptor–Negative Breast Cancer

BackgroundExpression of class ΙΙΙ β?tubulin (βΙΙΙ-tubulin) correlates with tumor progression and resistance to taxane-based therapies for several human malignancies including breast cancer. However its predictive value in a neoadjuvant setting in breast cancer remains unexplored. The objective of this explorative study was to determine whether βΙΙΙ-tubulin expression in breast cancer correlated with pathologic characteristics and whether its expression was predictive of response to neoadjuvant chemotherapy.Patients and MethodsWe determined βΙΙΙ-tubulin expression in 85 breast cancers, including 41 localized breast cancers treated with primary surgery and 44 treated with neoadjuvant chemotherapy before surgery. βΙΙΙ-tubulin expression was evaluated by immunohistochemical methods and was correlated with pathologic characteristics and response to neoadjuvant chemotherapy using residual cancer burden (RCB) score.ResultsHigh βΙΙΙ-tubulin expression was significantly associated with poorly differentiated high-grade breast cancers (P = .003) but not with tumor size, estrogen receptor (ER) status, or human epidermal growth factor receptor 2 (HER2)/neu overexpression. In ER^– tumors treated with neoadjuvant chemotherapy, high βΙΙΙ-tubulin expression was associated with a significantly greater likelihood of achieving a good pathologic response to chemotherapy as reflected by lower RCB scores (P = .021).ConclusionThis study reveals differential βΙΙΙ-tubulin expression in breast cancers of different histologic grades, hormone receptors, and HER2/neu status. It also suggests a potential role for βΙΙΙ-tubulin as a predictive biomarker for response in neoadjuvant chemotherapy for ER^– breast cancer, which has not been previously reported. These data provide a strong rationale for considering βΙΙΙ-tubulin status and further validation of this marker in a large study.     

Different criteria for HER2 positivity by IHC can be applied in post-chemotherapy specimens in determining HER2 as a prognosticator in locally advanced breast cancer

Purpose We evaluated the clinical significance of HER2 in post-chemotherapy specimens after surgery in locally advanced breast cancer (LABC). Methods Thirty-four patients with LABC were treated with neoadjuvant chemotherapy, surgery, adjuvant chemotherapy, and radiotherapy. The HER2 status was determined using both immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) in the paraffin-embedded surgical specimens after neoadjuvant chemotherapy. Results The positive rate of HER2 was 41.2% and 32.4% by IHC and FISH, respectively. As the gene copy number of HER2 detected by FISH increased, the staining intensity by IHC increased with positive correlation (adjusted r ² = 0.743; P < 0.001). According to the cutoff values of IHC score 2+ and 3+ as the positivity criteria, the concordance rates of IHC and FISH were 91.2% (31/34) and 88.2% (30/34), respectively. With the positivity criteria of IHC score ≥2+, the locoregional recurrence-free survival was better in the HER2-negative patients (P = 0.04). Trends were also found for the prolonged distant recurrence-free, disease-free, and overall survivals in the HER2-negative patients by IHC (2+). Trends for poor clinical response (P = 0.06) and more axillary nodes involvement (P = 0.08) were noted in the HER2-positive group by IHC (2+). In post-chemotherapy specimens, the positive HER2 status by IHC staining score ≥ 2+ predicted higher recurrence in LABC. Conclusion This suggests that different criteria for the HER2 positivity by IHC can be applied in post-chemotherapy specimens compared with that from pre-chemotherapy biopsies.     

Prognostic impact of discordance between triple-receptor measurements in primary and recurrent breast cancer

BackgroundWe evaluated discordance in expression measurements for estrogen receptor (ER), progesterone receptor (PR), and HER2 between primary and recurrent tumors in patients with recurrent breast cancer and its effect on prognosis.MethodsA total of 789 patients with recurrent breast cancer were studied. ER, PR, and HER2 status were determined by immunohistochemistry (IHC) and/or FISH. Repeat markers for ER, PR, and HER2 were available in 28.9%, 27.6%, and 70.0%, respectively. Primary and recurrent tumors were classified as triple receptor-negative breast cancer (TNBC) or receptor-positive breast cancer (RPBC, i.e. expressing at least one receptor). Discordance was correlated with clinical/pathological parameters.ResultsDiscordance for ER, PR, and HER2 was 18.4%, 40.3%, and 13.6%, respectively. Patients with concordant RPBC had significantly better post-recurrence survival (PRS) than discordant cases; patients with discordant receptor status had similarly unfavorable survival as patients with concordant TNBC. IHC scores for ER and PR showed weak concordance between primary and recurrent tumors. Concordance of HER2–FISH scores was higher.ConclusionsConcordance of quantitative hormone receptor measurements between primary and recurrent tumors is modest consistent with suboptimal reproducibility of measurement methods, particularly for IHC. Discordant cases have poor survival probably due to inappropriate use of targeted therapies. However, biological change in clinical phenotype cannot be completely excluded.     

Combined HER2 analysis of biopsies and surgical specimens to optimize detection of trastuzumab-eligible patients in eso-gastric adenocarcinoma: a GERCOR study

BackgroundHER2 is overexpressed in 10 to 20% of gastro-esophageal adenocarcinoma (GE-ADK), and is a target for trastuzumab in metastatic patients. We conducted a study to compare HER2 expression between diagnostic biopsies (DBs) and surgical specimens (SSs) of GE-ADK, and to determine the influence of non-trastuzumab containing neoadjuvant chemotherapy (NAC) on this expression.Patients and methodsPathological specimens from biopsies of 228 patients operated on between 2004 and 2011 were collected. Two cohorts treated (n = 141) or not (n = 87) with a NAC were constituted. Two blind independent pathological HER2 analyses on DB and on SS were carried out using immunohistochemistry (IHC) and colorimetric in situ hybridization (CISH). HER-2 overexpression (HER2+) was defined by a score 3+ in IHC, or 2+ with a positive CISH test, according to the specific HER2 scoring guidelines for GE-ADK.ResultsPaired HER2 status could be determined for 218 out of the 228 patients (95.6%). HER2+ rates were 13.3% on DB (29/218) and 14.7% on SS (32/218). HER2+ tumors were mainly cardial or esophageal adenocarcinomas, with a well-differentiated, intestinal histological type. HER2 status differed between DB and SS in 6% of cases. When DB analyses were added to SS analyses, the relative increase in HER2+ cases was 13.5% (17.1% for patients with NAC and 23.5% for patients with histological response to NAC, versus 7.1% for patients without NAC, P = 0.4, NS). Differences between DB and SS HER2 expression could be explained by intratumoral heterogeneity and by a HER2 expression decrease in SS after NAC in responding patients possibly due to a higher chemosensitivity of HER2-positive clones.ConclusionThe determination of HER2 status on DB provides results that complete those obtained with SS. Combining the analysis of DB and of SS enables to optimize the selection of trastuzumab-eligible patients in case of metastatic relapse, and particularly in previously NAC-responding patients.     

Effect of HER2 on prognosis and benefit from peri-operative chemotherapy in early oesophago-gastric adenocarcinoma in the MAGIC trial

BackgroundPerioperative epirubicin, cisplatin and fluorouracil (ECF) chemotherapy improves survival in operable oesophago-gastric cancer [Adjuvant Gastric Cancer Infusional Chemotherapy (MAGIC) trial HR 0.75 (0.6–0.93)]. HER2 amplification is reported to predict enhanced benefit from anthracyclines in breast cancer. We sought to define whether HER2 predicts benefit from ECF in oesophago-gastric cancer.Patients and methodsDiagnostic biopsies and/or resection specimens were collected from 415 of 503 MAGIC trial patients (82.5%). HER2 was evaluated by immunohistochemistry (IHC) and brightfield dual in situ hybridisation (BDISH) in tissue microarrays. The prognostic and predictive impact of HER2 status was investigated.ResultsConcordance between HER2 over-expression (IHC3+) and amplification was 96%. Results of HER2 assessment in biopsy and resection specimens were concordant in 92.9% (145/156). HER2 positive rate (IHC3+, or IHC2+/BDISH positive) was 10.9% in the whole cohort and 10.4% in resection specimens. A further 4.0% of resections were IHC negative/BDISH positive. HER2 status was neither prognostic, nor (in pre-treatment biopsies) predicted enhanced benefit from chemotherapy [HER2 positive HR 0.74 (0.14–3.77); HER2 negative HR 0.58 (0.41–0.82), interaction P = 0.7]. However, the power of the predictive analysis was limited by the small number of HER2 positive pre-treatment biopsies.ConclusionsHER2 status is not an independent prognostic biomarker in early oesophago-gastric adenocarcinoma.     

Alterations of biomarker profiles after neoadjuvant chemotherapy in breast cancer: tumor heterogeneity should be taken into consideration

Tumor biomarkers including estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) and Ki-67 are routinely tested in breast cancer patients and their status guides clinical management and predicts prognosis. A few retrospective studies have suggested that neoadjuvant chemotherapy (NAC) in breast cancer may change the status of biomarker expression, which in turn will affect further management of these patients. In this study we take advantage of a relatively large cohort and aim to study the effect of NAC on biomarker expression and explore the impact of tumor size and lymph node involvement on biomarker status changes. We collected 107 patients with invasive breast cancer who received at least three cycles of NAC. We retrospectively performed and scored the immunohistochemistry (IHC) of ER, PR, HER2 and Ki-67 using both the diagnostic core biopsies before NAC and excisional specimens following NAC. HER2 gene status was assessed by fluorescence in situ hybridization for cases with IHC result of 2+. We demonstrated that there was a significant decrease in expression of PR (P = 0.013) and Ki-67 (P = 0.000) in post-NAC specimens compared to pre-NAC core biopsies. In addition, cases with large tumor size (≥2cm) and cases with lymph node metastasis were more frequently to have biomarker changes. Finally we studied cases with HER2 status changes after NAC treatments in detail and emphasized the nature of tumor heterogeneity.     

Determination of HER2 Gene Amplification by Fluorescence <Emphasis Type="Italic">In situ</Emphasis> Hybridization and Concordance with the Clinical Trials Immunohistochemical Assay in Women with Metastatic Breast Cancer Evaluated for Treatment with Trastuzumab

Summary Purpose. To evaluate the concordance between HER2 gene amplification, determined by fluorescence in situ hybridization (FISH), and HER2 protein overexpression assessed by an immunohistochemical (IHC) assay. The IHC protocol used was a research assay, known as the Clinical Trial Assay (CTA), developed to select women with metastatic breast cancer (MBC) for three pivotal clinical trials of trastuzumab therapy. Methods. A direct-labeled, dual-probe FISH assay was used to determine HER2 amplification in 623 fixed breast cancer tissue specimens. These specimens had been stored as paraffin-embedded sections for 2ᾢ5 years. All specimens had been analyzed for HER2 protein expression by the CTA. To assess the reproducibility of FISH results in archived material, we evaluated a separate group of 617 breast cancer tissue specimens at two di erent laboratories. Results. Informative FISH results were available for 529 (85%) of the 623 specimens. Overall concordance between FISH and IHC results was 82% (95% CI; 78ᾢ85%). Assay agreement between FISH results and specimens with immunostaining scores of 0, 1+, and 3+ were 97, 93 and 89%, respectively. However, only 24% of specimens with 2+ immunostaining scores had HER2 amplification by FISH; there was assay disagreement in 76% of specimens in this IHC subgroup. Interlaboratory FISH concordance was 92% (95% CI; 89ᾢ94%), indicating very good assay reproducibility in these archived specimens. Conclusion. HER2 status determined by CTA-IHC and FISH are significantly correlated; however, differences between these two assays can a ect patient selection for trastuzumab therapy.     

HER2 and response to anthracycline-based neoadjuvant chemotherapy in breast cancer

BackgroundThe predictive role of human epidermal growth factor receptor 2 (HER2) to adjuvant anthracycline-based chemotherapy remains controversial. Here, we investigated the association between HER2 status and pathological response in breast cancer patients who received neoadjuvant anthracycline-based regimens.Patients and methodsWomen (n = 538) with operable primary breast cancer received neoadjuvant anthracycline-based chemotherapy. Pathological complete response (pCR) was defined as no invasive breast tumor cells in breast after completion of neoadjuvant chemotherapy. HER2 status was determined by immunohistochemistry and/or by fluorescence in situ hybridization in core biopsy breast cancer tissue obtained before initiation of neoadjuvant chemotherapy.ResultsIn this cohort of 538 patients, 23.9% of patients achieved a pCR in their breast. HER2-positive tumors had a lower rate of pCR than did HER2-negative tumors (14.7% versus 25.7%, P = 0.013); negative HER2 status remained as an independent favorable predictor of pCR after adjusted for age, estrogen receptor, progesterone receptor, tumor size, chemotherapy cycles, and tumor grade in a multivariate analysis (odds ratio = 3.14; 95% confidence interval = 1.60–6.16, P = 0.001). Furthermore, patients with a pCR had a higher 3-year disease-free survival (DFS) rate than did patients without a pCR (P = 0.007).ConclusionWomen with HER2-negative breast cancers rather than HER2-positive tumors benefit from anthracycline-based neoadjuvant chemotherapy.     

Concordant HER2 status between metastatic breast cancer cells in CSF and primary breast cancer tissue

It is not known whether the HER2 status of malignant CSF cells coincides with that of the original breast carcinoma cells. We investigated whether CSF cytology specimens were suitable to evaluate HER2 status by fluorescence in situ hybridization (FISH) in patient with leptomeningeal metastasis (LM). Both formalin-fixed paraffin-embedded (FFPE) breast cancer tissue and liquid based CSF cytology specimens were evaluated for HER2 status in 16 patients with LM. We evaluated HER2 gene amplification using FISH on destained CSF cytology slides containing a minimum of 20 malignant cells per slide, and compared these with the HER2 status by immunohistochemistry (IHC) or FISH in FFPE tissues. HER2 was considered positive when the HER2:CEP17 ratio was ≥2.0 or IHC 3+. Of 16 cases, four were HER2 positive and 12 were HER2 negative by FISH analysis in CSF cytology. All CSF-positive cases were HER2 positive by IHC in FFPE tissue. Of 12 HER2 FISH-negative cases in CSF cytology, 10 were HER2 negative (IHC 0 or 1+) and two were IHC 2+ in FFPE tissue. Two IHC 2+ cases had HER2:CEP17 ratios of 1.27 and 2.1, respectively, by FISH in FFPE tissue. As a result, the HER2 status concordance rate between metastatic breast cancer cells in CSF and FFPE primary tissue by IHC and FISH was very high. When CSF cytology specimens were appropriately prepared and had adequate cellularity without dry artifacts, the CSF cytology was suitable to evaluate HER2 status by FISH analysis in patients with LM.     

Comparison of HER2 status by fluorescence in situ hybridization and immunohistochemistry to predict benefit from dose escalation of adjuvant doxorubicin-based therapy in node-positive breast cancer patients.

PURPOSE: HER2 is a clinically important tumor marker in breast cancer; however, there is controversy regarding which method reliably measures HER2 status. We compared three HER2 laboratory methods: immunohistochemistry (IHC), fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR), to predict disease-free survival (DFS) and overall survival (OS) after adjuvant doxorubicin-based therapy in node-positive breast cancer patients. METHODS: This is a Cancer and Leukemia Group B (CALGB) study, using 524 tumor blocks collected from breast cancer patients registered to clinical trial CALGB 8541. IHC employed CB11 and AO-11-854 monoclonal antibodies; FISH used PathVysion HER2 DNA Probe kit; PCR utilized differential PCR (D-PCR) methodology. RESULTS: Cases HER2 positive by IHC, FISH and D-PCR were 24%, 17%, and 18%, respectively. FISH and IHC were clearly related (kappa = 64.8%). All three methods demonstrated a similar relationship for DFS and OS. By any method, for patients with HER2-negative tumors, there was little or no effect of dose of adjuvant doxorubicin-based therapy. For patients with HER2-positive tumors, all three methods predicted a benefit from dose-intense (high-dose) compared with low- or moderate-dose adjuvant doxorubicin-based therapy. CONCLUSION: FISH is a reliable method to predict clinical outcome following adjuvant doxorubicin-based therapy for stage II breast cancer patients. There is a moderate level of concordance among the three methods (IHC, FISH, PCR). None of the methods is clearly superior. Although IHC-positive/FISH-positive tumors yielded the greatest interaction with dose of therapy in predicting outcome, no combination of assays tested was statistically superior.     

Evaluation of HER-2/NEU protein expression in breast cancer by immunohistochemistry: an interlaboratory study assessing the reproducibility of HER-2/NEU testing

This study investigated the degree of interlaboratory agreement when HER-2/neu was evaluated by immunohistochemistry (IHC) on archival primary breast cancer samples. IHC for HER-2/neu was performed on the same archival tissue sections from 394 invasive primary breast cancers in two different laboratories. Both laboratories used the primary antibody NCL-CB11; however, different methods of immunostaining (antigen retrieval procedure and manual processing or no antigen retrieval and autostainer processing) as well as different scoring systems were used. Fluorescence in situ hybridization (FISH), considered as the correlation method for HER-2/neu status determination, was performed using the PathVysion kit and compared to the IHC results. Forty-eight of 394 analyzed tumors (12.2%) were scored as HER-2/neu positive in one laboratory, and 109 (27.7%) in the other laboratory where antigen retrieval was performed. Complete concordance in categorization of HER-2/neu status between the two laboratories was achieved in 333 of 394 cases (84.5%). FISH performed in 248 formalin-fixed samples revealed HER-2/neu gene amplification in 55/248 (22.2%). Concordance of FISH and IHC was found in 211/248 cases (85.1%) and 220/248 cases (88.7%) when the CB11 antibody was used without and with antigen retrieval, respectively. Both IHC methods generated similar rates of false results, but with different positive predictive values. Our data demonstrate that HER-2/neu evaluation by IHC is not a reproducible technique if there is no standardization of the procedure.     

Pathologic Complete Response to Preoperative Sequential Doxorubicin/Cyclophosphamide and Single-Agent Taxane With or Without Trastuzumab in Stage II/III HER2-Positive Breast Cancer

BackgroundFour major clinical trials have established that trastuzumab added to adjuvant systemic chemotherapy for women with HER2⁺ breast cancer significantly improves disease-free and overall survival compared with chemotherapy alone. We evaluated pathologic complete response (pCR) rate and cardiac safety of preoperative doxorubicin and cyclophosphamide followed by a taxane with or without trastuzumab.Patients and MethodsWe reviewed pCR rate and change in left ventricular ejection fraction in women with operable HER2⁺ breast cancer (defined as immunohistochemical 3+ or fluorescence in situ hybridization ratio ≥ 2.2) who were treated between 2002 and 2008 with doxorubicin and cyclophosphamide followed by a taxane with or without trastuzumab before definitive breast surgery.ResultsWe identified 33 patients, of whom 42.4% received preoperative chemotherapy without trastuzumab and 57.6% of whom received trastuzumab with chemotherapy. The pCR rates were 28.6% and 52.6% in the group that received chemotherapy alone or with trastuzumab, respectively (odds ratio, 2.78; 95% CI, 0.64-12.1; P = .173). Severe cardiac events or treatment delays as a result of cardiac toxicity were not observed. With a median follow-up time of 14 months, 21.4% of patients in the non-trastuzumab group and 10.5% in the trastuzumab group had disease recurrence.ConclusionSequential administration of preoperative doxorubicin and cyclophosphamide followed by a taxane and trastuzumab combination is safe in women with primary operable HER2⁺ breast cancer and is associated with a high pCR rate. Large randomized phase III clinical trials are evaluating the role of preoperative trastuzumab when added to anthracycline- and/or taxane-based regimens.     

Assessing HER2 gene amplification as a potential target for therapy in invasive urothelial bladder cancer with a standardized methodology: results in 1005 patients

BackgroundThis study assessed the human epidermal growth factor receptor-2 (HER2) protein expression and its relationship with gene amplification in invasive bladder carcinoma, using the same criteria than for breast cancer.Patients and methodsIn 1005 patients, paraffin-embedded tissues of transurethral resection or cystectomy were evaluated by immunohistochemistry (IHC), using antibodies against HER2. All samples with a 2+ or 3+ HER2 overexpression were evaluated by FISH.ResultsHER2 overexpression was observed in 93 (9.2%) tumors (2+: 42 tumors and 3+: 51 tumors). Using FISH, all HER2 3+ tumors had a gene amplification, whereas no amplification was found in 2+ tumors. Intratumoral heterogeneity was observed in 35% of cases. These tumors showed the same heterogeneous pattern, with adjacent 3+ positive and negative areas by both IHC and FISH.ConclusionsThis study showed that 5.1% of invasive bladder carcinomas had a HER2 gene amplification. These findings may have clinical implications for the management of patients with HER2-positive locally advanced or metastatic bladder cancer, as they could be potential candidates for targeted therapy.     

The role of HER2/neu expression and trastuzumab in non-small cell lung cancer

Research over the past decade has led to an increased understanding of the pathophysiology of lung cancer. The HER2/neu receptor is a member of the ErbB family of signaling-transduction receptors and appears to play a major role in the development of lung cancer as well as many other solid tumors. HER2/neu is overexpressed in 16% to 57% of patients with non-small cell lung cancer (NSCLC) and studies have shown that HER2/neu overexpression imparts a poor prognosis in both resected and advanced NSCLC, as it does in breast cancer. Trastuzumab, a humanized monoclonal antibody that recognizes the HER2/neu protein receptor, has been approved by the US Food and Drug Administration for patients with HER2/neu-positive metastatic breast cancer. In NSCLC preclinical studies, marked synergistic growth inhibition occurred when standard cytotoxic chemotherapy was combined with trastuzumab in HER2/neu-expressing cell lines. In the clinical setting, trastuzumab has proven safe and feasible in combination with cytotoxic chemotherapy in both single-institution and multi-institutional cooperative group studies. Unlike the experience in advanced breast cancer, cardiac toxicity is a marginal concern in this population. However, to date, clinical studies with trastuzumab in patients with NSCLC have not shown a demonstrable advantage for the majority of patients.     

A combinatorial biomarker predicts pathologic complete response to neoadjuvant lapatinib and trastuzumab without chemotherapy in patients with HER2+ breast cancer

BackgroundHER2-positive (+) breast cancers, defined by HER2 overexpression and/or amplification, are often addicted to HER2 to maintain their malignant phenotype. Yet, some HER2+ tumors do not benefit from anti-HER2 therapy. We hypothesize that HER2 amplification levels and PI3K pathway activation are key determinants of response to HER2-targeted treatments without chemotherapy.Patients and methodsBaseline HER2+ tumors from patients treated with neoadjuvant lapatinib plus trastuzumab [with endocrine therapy for estrogen receptor (ER)+ tumors] in TBCRC006 (NCT00548184) were evaluated in a central laboratory for HER2 amplification by fluorescence in situ hybridization (FISH) (n = 56). HER2 copy number (CN) and FISH ratios, and PI3K pathway status, defined by PIK3CA mutations or PTEN levels by immunohistochemistry were available for 41 tumors. Results were correlated with pathologic complete response (pCR; no residual invasive tumor in breast).ResultsThirteen of the 56 patients (23%) achieved pCR. None of the 11 patients with HER2 ratio <4 and/or CN <10 achieved pCR, whereas 13/45 patients (29%) with HER2 ratio ≥4 and/or CN ≥10 attained pCR (P = 0.0513). Of the 18 patients with tumors expressing high PTEN or wild-type (WT) PIK3CA (intact PI3K pathway), 7 (39%) achieved pCR, compared with 1/23 (4%) with PI3K pathway alterations (P = 0.0133). Seven of the 16 patients (44%) with HER2 ratio ≥4 and intact PI3K pathway achieved pCR, whereas only 1/25 (4%) patients not meeting these criteria achieved pCR (P = 0.0031).ConclusionsOur findings suggest that there is a clinical subtype in breast cancer with high HER2 amplification and intact PI3K pathway that is especially sensitive to HER2-targeted therapies without chemotherapy. A combination of HER2 FISH ratio and PI3K pathway status warrants validation to identify patients who may be treated with HER2-targeted therapy without chemotherapy.     

HER2 staining intensity in HER2-positive disease: relationship with FISH amplification and clinical outcome in the HERA trial of adjuvant trastuzumab

BackgroundTrastuzumab treatment improves survival of HER2-positive primary breast cancer. HER2 staining intensity varies widely in HER2-positive tumours.Patients and methodsWe investigated whether differences in immunohistochemical (IHC) staining intensity for HER2 in HER2-positive tumors (IHC 3+ or FISH ratio ≥2.0) was associated with prognosis or benefit from trastuzumab treatment in patients randomized to 1 year or no trastuzumab in the HERceptin Adjuvant (HERA) trial. Median follow-up was 2 years. The nested case–control analysis, included 425 patients (cases) with a disease-free survival (DFS) event and two matched controls (no DFS event) per case. Tissue sections stained for HER2 were assessed for HER2 staining intensity by image analysis.ResultsHER2 staining intensity varied widely and correlated with HER2 gene copy number (Spearman, r = 0.498, P < 0.001) or less closely with HER2/CEP17 FISH ratio (r = 0.396, P < 0.001). We found no significant difference in DFS in the observation arm according to staining intensity (odds ratio [OR] change per 10 unit change in intensity: 1.015, 95% confidence interval [CI] 0.930–1.108) and no impact of staining intensity on benefit derived from 1-year trastuzumab (OR: 1.017, 95% CI 0.925–1.120).ConclusionsVariability in HER2 staining in HER2-positive tumours has no role in clinical management with adjuvant trastuzumab.HERA trial noNCT00045032.     

TOP2A amplification in the absence of that of HER-2/neu: toward individualization of chemotherapeutic practice in breast cancer

Primary objective.

To investigate the relationship between human epidermal growth factor receptor (HER)-2/neu and the gene encoding topoisomerase IIα (TOP2A) in breast cancer, while elucidating their association with clinicopathological variables.

Methods.

Real-time quantitative polymerase chain reaction (RQ-PCR) was performed on a 96-patient study group to assess gene amplification, and levels were determined using the comparative cycle threshold approach and Taqman assays. An immunohistochemistry (IHC) microarray (n = 76) was then employed to check for correlation between gene amplification and protein expression levels.

Results.

Amplification levels of TOP2A did not differ significantly according to HER-2/neu status by either RQ-PCR or IHC microarray. Of the HER-2/neu⁻ patients, 29.1% demonstrated levels of TOP2A above the third quartile, whereas 22.9% of the HER-2/neu⁺ patients had values in the first quartile (log TOP2A <0.62), thereby indicating low-level amplification. Of the 60 patients characterized as HER-2/neu⁻ using IHC and fluorescence in situ hybridization (FISH), 22.9% were classified as TOP2A⁺ on the IHC microarray. Of the 14 patients deemed HER-2/neu⁺ using IHC and FISH, meanwhile, the majority (n = 10) were classified as TOP2A⁺.

Conclusions.

Our results indicate that amplification of TOP2A in breast cancer is not confined to those who are concomitantly HER-2/neu⁺, and suggest that a significant proportion of HER-2/neu⁻ patients exhibit high levels of TOP2A.     

Integrating bevacizumab,everolimus, and lapatinib into current neoadjuvant chemotherapy regimen for primary breast cancer. Safety results of the GeparQuinto trial

BackgroundSafety data for combining bevacizumab, everolimus, or lapatinib with anthracycline- and taxane-based neoadjuvant chemotherapy for breast cancer are limited.Patients and methodsThe neoadjuvant GeparQuinto trial investigates the addition of (i) bevacizumab to four cycles epirubicin/cyclophosphamide (EC) followed by four cycles docetaxel (Taxotere) in patients with human epithelial growth factor receptor (HER)2-negative tumors, (ii) everolimus to weekly paclitaxel in patients with HER2-negative tumors not responding to EC ± bevacizumab, and (iii) lapatinib instead of trastuzumab to EC–docetaxel in patients with HER2-positive tumors to improve the rate of pathological complete response. Tolerable dose, need for supportive treatments, and early signals for toxic effect were evaluated in a planned safety analysis of 270 patients.ResultsTreatment with chemotherapy plus bevacizumab, everolimus, or lapatinib was discontinued in 23.0%, 25.8%, and 34.5% compared with chemotherapy alone or plus trastuzumab in 19.4%, 24.1%, 3.2%, respectively. More leukopenia, infections, mucositis, and hypertension but less edema was observed by adding bevacizumab; a trend toward more thrombocytopenia, leukopenia, skin changes, and hyperlipidemia by adding everolimus; and more diarrhea, skin changes, and hot flushes but no cardiac events by substituting trastuzumab by lapatinib.ConclusionsAdding bevacizumab and everolimus to chemotherapy appeared feasible. Lapatinib at 1250 mg resulted in an increased rate of treatment discontinuations and was subsequently dose reduced to 1000 mg.