Neratinib + fulvestrant + trastuzumab for HR-positive, HER2-negative, HER2-mutant metastatic breast cancer: outcomes and biomarker analysis from the SUMMIT trial.

BACKGROUND: HER2 mutations are targetable alterations in patients with hormone receptor-positive (HR+) metastatic breast cancer (MBC). In the SUMMIT basket study, patients with HER2-mutant MBC received neratinib monotherapy, neratinib + fulvestrant, or neratinib + fulvestrant + trastuzumab (N + F + T). We report results from 71 patients with HR+, HER2-mutant MBC, including 21 (seven in each arm) from a randomized substudy of fulvestrant versus fulvestrant + trastuzumab (F + T) versus N + F + T. PATIENTS AND METHODS: Patients with HR+ HER2-negative MBC with activating HER2 mutation(s) and prior cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) therapy received N + F + T (oral neratinib 240 mg/day with loperamide prophylaxis, intramuscular fulvestrant 500 mg on days 1, 15, and 29 of cycle 1 then q4w, intravenous trastuzumab 8 mg/kg then 6 mg/kg q3w) or F + T or fulvestrant alone. Those whose disease progressed on F + T or fulvestrant could cross-over to N + F + T. Efficacy endpoints included investigator-assessed objective response rate (ORR), clinical benefit rate (RECIST v1.1), duration of response, and progression-free survival (PFS). Plasma and/or formalin-fixed paraffin-embedded tissue samples were collected at baseline; plasma was collected during and at end of treatment. Extracted DNA was analyzed by next-generation sequencing. RESULTS: ORR for 57 N + F + T-treated patients was 39% [95% confidence interval (CI) 26% to 52%); median PFS was 8.3 months (95% CI 6.0-15.1 months). No responses occurred in fulvestrant- or F + T-treated patients; responses in patients crossing over to N + F + T supported the requirement for neratinib in the triplet. Responses were observed in patients with ductal and lobular histology, 1 or ≥1 HER2 mutations, and co-occurring HER3 mutations. Longitudinal circulating tumor DNA sequencing revealed acquisition of additional HER2 alterations, and mutations in genes including PIK3CA, enabling further precision targeting and possible re-response. CONCLUSIONS: The benefit of N + F + T for HR+ HER2-mutant MBC after progression on CDK4/6is is clinically meaningful and, based on this study, N + F + T has been included in the National Comprehensive Cancer Network treatment guidelines. SUMMIT has improved our understanding of the translational implications of targeting HER2 mutations with neratinib-based therapy.

Overall survival in the OlympiA phase III trial of adjuvant olaparib in patients with germline pathogenic variants in BRCA1/2 and high-risk, early breast cancer.

BACKGROUND: The randomized, double-blind OlympiA trial compared 1 year of the oral poly(adenosine diphosphate-ribose) polymerase inhibitor, olaparib, to matching placebo as adjuvant therapy for patients with pathogenic or likely pathogenic variants in germline BRCA1 or BRCA2 (gBRCA1/2pv) and high-risk, human epidermal growth factor receptor 2-negative, early breast cancer (EBC). The first pre-specified interim analysis (IA) previously demonstrated statistically significant improvement in invasive disease-free survival (IDFS) and distant disease-free survival (DDFS). The olaparib group had fewer deaths than the placebo group, but the difference did not reach statistical significance for overall survival (OS). We now report the pre-specified second IA of OS with updates of IDFS, DDFS, and safety. PATIENTS AND METHODS: One thousand eight hundred and thirty-six patients were randomly assigned to olaparib or placebo following (neo)adjuvant chemotherapy, surgery, and radiation therapy if indicated. Endocrine therapy was given concurrently with study medication for hormone receptor-positive cancers. Statistical significance for OS at this IA required P < 0.015. RESULTS: With a median follow-up of 3.5 years, the second IA of OS demonstrated significant improvement in the olaparib group relative to the placebo group [hazard ratio 0.68; 98.5% confidence interval (CI) 0.47-0.97; P = 0.009]. Four-year OS was 89.8% in the olaparib group and 86.4% in the placebo group (Δ 3.4%, 95% CI -0.1% to 6.8%). Four-year IDFS for the olaparib group versus placebo group was 82.7% versus 75.4% (Δ 7.3%, 95% CI 3.0% to 11.5%) and 4-year DDFS was 86.5% versus 79.1% (Δ 7.4%, 95% CI 3.6% to 11.3%), respectively. Subset analyses for OS, IDFS, and DDFS demonstrated benefit across major subgroups. No new safety signals were identified including no new cases of acute myeloid leukemia or myelodysplastic syndrome. CONCLUSION: With 3.5 years of median follow-up, OlympiA demonstrates statistically significant improvement in OS with adjuvant olaparib compared with placebo for gBRCA1/2pv-associated EBC and maintained improvements in the previously reported, statistically significant endpoints of IDFS and DDFS with no new safety signals.

Efficacy of PI3K inhibitors in advanced breast cancer.

The phosphoinositide 3 (PI3)-kinase/Akt signaling pathway has always been a focus of interest in breast cancer due to its role in cell growth, cell proliferation, cell migration and deregulated apoptosis. Its activation has been linked to endocrine resistance and worse prognosis in certain subgroups of breast cancer. In addition, deregulation of the PI3K/Akt pathway including PIK3CA activating mutation is frequently present in breast cancer. Multiple efforts have been carried out to target this pathway, initially with pan-PI3K inhibitors with some hint of activity but hampered by their limiting side-effects. A recent large randomized trial in patients with endocrine-resistant PIK3CA-mutant hormone receptor (HR)-positive tumors led to the approval of the first PI3K inhibitor, alpelisib, in combination with fulvestrant. The specificity of alpelisib against the p110α catalytic isoform provided additional efficacy and a better toxicity profile. In this review, we summarize the main research with PI3K inhibitors in breast cancer and we provide some insight of potential future combinations of this treatment in breast cancer patients.

Efficacy of PI3K inhibitors in advanced breast cancer.

The phosphoinositide 3 (PI3)-kinase/Akt signaling pathway has always been a focus of interest in breast cancer due to its role in cell growth, cell proliferation, cell migration and deregulated apoptosis. Its activation has been linked to endocrine resistance and worse prognosis in certain subgroups of breast cancer. In addition, deregulation of the PI3K/Akt pathway including PIK3CA activating mutation is frequently present in breast cancer. Multiple efforts have been carried out to target this pathway, initially with pan-PI3K inhibitors with some hint of activity but hampered by their limiting side-effects. A recent large randomized trial in patients with endocrine-resistant PIK3CA-mutant hormone receptor (HR)-positive tumors led to the approval of the first PI3K inhibitor, alpelisib, in combination with fulvestrant. The specificity of alpelisib against the p110α catalytic isoform provided additional efficacy and a better toxicity profile. In this review, we summarize the main research with PI3K inhibitors in breast cancer and we provide some insight of potential future combinations of this treatment in breast cancer patients.

T-cell bispecific antibodies in node-positive breast cancer: novel therapeutic avenue for MHC class I loss variants.

BACKGROUND: Tumor-infiltrating lymphocytes (TILs) represent a prognostic factor for survival in primary breast cancer (BC). Nonetheless, neoepitope load and TILs cytolytic activity are modest in BC, compromising the efficacy of immune-activating antibodies, which do not yet compete against immunogenic chemotherapy. PATIENTS AND METHODS: We analyzed by functional flow cytometry the immune dynamics of primary and metastatic axillary nodes [metastatic lymph nodes (mLN)] in early BC (EBC) after exposure to T-cell bispecific antibodies (TCB) bridging CD3ε and human epidermal growth factor receptor 2 (HER2) or Carcinoembryonic Antigen-Related Cell Adhesion Molecule 5 (CEACAM5), before and after chemotherapy. Human leukocyte antigen (HLA) class I loss was assessed by whole exome sequencing and immunohistochemistry. One hundred primary BC, 64 surrounding 'healthy tissue' and 24 mLN-related parameters were analyzed. RESULTS: HLA loss of heterozygosity was observed in EBC, at a clonal and subclonal level and was associated with regulatory T cells and T-cell immunoglobulin and mucin-domain-3 expression restraining the immuno-stimulatory effects of neoadjuvant chemotherapy. TCB bridging CD3ε and HER2 or CEACAM5 could bypass major histocompatibility complex (MHC) class I loss, partially rescuing T-cell functions in mLN. CONCLUSION: TCB should be developed in BC to circumvent low MHC/peptide complexes.

Modulation of Rb phosphorylation and antiproliferative response to palbociclib: the preoperative-palbociclib (POP) randomized clinical trial.

Background: The cyclin-dependent kinase 4 (CDK4)/6 inhibitor Palbociclib is a new standard treatment in hormone-receptor positive breast cancer patients. No predictive biomarkers have been identified and no pharmacodynamics has properly been described so far. Patients and methods: Patients with early-breast cancer were randomized 3 : 1 to oral palbociclib 125 mg daily for 14 days until the day before the surgery versus no treatment. Primary objective was antiproliferative response defined as a natural logarithm of Ki67 expression at day 15 below 1. Secondary end points were subgroups analyses and safety. Exploratory analyses included search for predictive biomarkers. Immunostainings (Ki67, RB, pRB, p16, pAKT, pER, pCDK2, CyclinD1), FISH (CCND1) and gene expression (GE) arrays were carried out at baseline and at surgery. In addition, activating PIK3CA and AKT1 mutations were assessed at baseline. Results: 74 patients were allocated to palbociclib and 26 to control. Most patients (93%) were hormone-receptor (HR)-positive, whereas 8% were HER2-positive. Palbociclib led to significantly more antiproliferative responses when compared with control (58% versus 12%, P < 0.001), and to a significantly higher Ki67 decrease (P < 0.001). In the HR-positive/HER2-negative subgroup, this antiproliferative effect was even more marked in the palbociclib arm when compared with control (70% versus 9%, P < 0.001). Palbociclib treatment led also to a significantly higher decrease from baseline in phospho-Rb when compared with control (P < 0.001). Among treated patients, changes in Ki67 correlated with changes in phospho-Rb (Spearman rank r = 0.41, P < 0.0001). GE analyses confirmed a major effect on proliferation and cell cycle genes. Among treated patients, CCNE2 expression was significantly more decreased in antiproliferative responders versus nonresponders (P = 0.006). Conclusion: Short-term preoperative palbociclib decreases Ki67 in early-breast cancer patients. Early decrease of Rb phosphorylation correlates with drug's effect on cell proliferation and could potentially identify patients with primary resistance. Clinical trial registration: NCT02008734.

Translational studies within the TAMRAD randomized GINECO trial: evidence for mTORC1 activation marker as a predictive factor for everolimus efficacy in advanced breast cancer.

BACKGROUND: Everolimus is an agent frequently associated with specific toxicities. Predictive markers of efficacy are needed to help define which patients could benefit from it. The goal of this exploratory study was to identify potential predictive biomarkers in the mammalian target of rapamycin (mTOR) complex 1 (mTORC1) activation pathway using primary tumor samples collected during the phase II tamoxifen plus everolimus (TAMRAD) trial. PATIENTS AND METHODS: Tumor tissues were collected retrospectively from the TAMRAD trial. Immunohistochemistry was carried out using specific antibodies directed toward proteins that result in mTORC1 activation [canonical phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/mTOR or alternative pathways]. DNA was extracted from the tumor tissue; mutation screening in the PIK3CA gene (exons 9 and 20) and the KRAS gene (exons 2 and 3) was first carried out using Sanger direct sequencing, and then completed by next-generation sequencing for PIK3CA. An exploratory analysis of everolimus efficacy in terms of a time-to-progression (TTP) increase was carried out in each biomarker subgroup (high versus low expression referring to the median percentage of marked cells). RESULTS: A total of 55 primary tumor samples from the TAMRAD trial­25 from the tamoxifen-alone group and 30 from the tamoxifen/everolimus group­were evaluated for biomarkers. The subgroups most likely to have an improvement in TTP with tamoxifen/everolimus therapy, compared with tamoxifen alone, were patients with high p4EBP1, low 4EBP1, low liver kinase B1, low pAkt, and low PI3K. Among the 45 samples screened for mutation status, nine samples (20%; 95% CI 9.6-34.6) had a PIK3CA mutation. KRAS mutation was observed in one patient. CONCLUSIONS: A positive correlation between late effectors of mTORC1 activation, a positive correlation between Akt-independent mTORC1 activation, and an inverse correlation between canonical PI3K/Akt/mTOR pathway and everolimus efficacy were observed in this exploratory analysis. However, these correlations need to be validated in larger studies before applying the findings to routine clinical practice.

Biomarker changes associated with the development of resistance to aromatase inhibitors (AIs) in estrogen receptor-positive breast cancer.

BACKGROUND: The purpose of this study was to identify any differences in key biomarkers associated with estrogen action between biopsies taken at diagnosis and at recurrence or progression during treatment with an aromatase inhibitor (AI). PATIENTS AND METHODS: Patients were retrospectively identified from a clinical database as having relapsed or progressed during AI treatment. Immunohistochemistry was carried out against estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor 2 (HER2), insulin-like growth factor type-1 receptor (IGF1R), insulin receptor substrate-1 (IRS-1), stathmin, phosphatase and tensin homolog and Ki67. RESULTS: Fifty-five pairs of samples were identified with ER- and/or PgR-positive diseases. Four (7%) patients were ER-negative at progression. Overall, PgR levels were lower in the recurrence sample, but 35% of cases remained positive. IGF1R levels decreased significantly. There were no substantial changes in HER2, IRS-1 or stathmin levels to indicate a role in resistance. Higher Ki67 levels at resistance indicate more proliferative disease. CONCLUSIONS: The phenotype of AI-recurrent lesions shows high between-tumour heterogeneity. There is evidence of an increase in Ki67, a reduction in IGF1R and a loss of ER expression in some individuals and some activation of growth factor signalling pathways that may explain resistance in individuals and merit treatment targeted to those pathways. Biopsy at recurrence will be necessary to identify the relevant target for individuals.

Elacestrant in ESR1-mutant, endocrine-responsive metastatic breast cancer: should health authorities consider post hoc data to inform priority access?

For patients with hormone receptor-positive/human epidermal growth factor receptor 2 (HER2)-negative (HR+/HER2-) metastatic breast cancer (mBC) progressed on first-line endocrine therapy plus a cyclin-dependent kinase 4 and 6 inhibitor (CDK4/6i), fulvestrant, a selective estrogen receptor degrader (SERD) administered intramuscularly, represented the only monotherapy option until the approval of elacestrant. This oral SERD has been approved for patients with ESR1-mutant HR+/HER2- mBC by the European Medicines Agency, the Food and Drug Administration, and the UK Medicines and Healthcare products Regulatory Agency, according to the results of the randomized phase III EMERALD trial, which demonstrated elacestrant superiority over standard endocrine monotherapy. Consequently, elacestrant has been incorporated in the European Society for Medical Oncology and American Society of Clinical Oncology guidelines. However, in Europe, the access to this recommended drug depends on the decision of the National Health Authorities of each state. In this communication, we describe the main results and implications of the EMERALD trial, in the context of the biomarker-driven algorithm for patients with HR+/HER2- mBC progressed on CDK4/6i, and conclude that a subgroup of patients with ESR1-mutant tumors and specific clinical features can really derive a clinically meaningful benefit from elacestrant, sparing access to more toxic combination approaches and preserving the quality of life.

Incidence and outcome of brain and/or leptomeningeal metastases in HER2-low metastatic breast cancer in the French ESME cohort.

BACKGROUND: Breast cancer (BC) is the second most common cancer that metastasizes to the brain. Particularly up to half of patients with human epidermal growth factor receptor 2 (HER2)-positive (HER2+) metastatic breast cancer (mBC) may develop brain metastases over the course of the disease. Nevertheless, little is known about the prevalence and the outcome of brain and leptomeningeal metastases (BLMM) in HER2-low BC. We compared the cumulative incidence of BLMM and associated outcomes among patients with HER2-low, HER2-negative (HER2-) and HER2+ mBC. PATIENTS AND METHODS: This cohort study was conducted from the Epidemiological Strategy and Medical Economics (ESME) mBC database and included patients treated for mBC between 2012 and 2020 across 18 French comprehensive cancer centers and with known HER2 and hormone receptor (HR) status. The cumulative incidence of BLMM after metastatic diagnosis was estimated using a competing risk methodology with death defined as a competing event. RESULTS: 19 585 patients were included with 6118 (31.2%), 9943 (50.8%) and 3524 (18.0%) being HER2-low, HER2- and HER2+ mBC, respectively. After a median follow-up of 48.6 months [95% confidence interval (CI) 47.7-49.3 months], BLMM were reported in 4727 patients: 1192 (25.2%) were diagnosed with BLMM at first metastatic diagnosis and 3535 (74.8%) after metastatic diagnosis. Multivariable analysis adjusted for age, histological grade, metastases-free interval and HR status showed that the risk of BLMM at metastatic diagnosis was similar in patients with HER2- compared to HER2-low mBC [odds ratio (OR) (95% CI) 1.00 (0.86-1.17)] and higher in those with HER2+ compared to HER2-low [OR (95% CI) 2.23 (1.87-2.66)]. Similar results were found after metastatic diagnosis; the risk of BLMM was similar in HER2- compared to HER2-low [subdistribution hazard ratio (sHR) (95% CI) 1.07 (0.98-1.16)] and higher in the HER2+ group [sHR (95% CI) 1.56 (1.41-1.73)]. CONCLUSIONS: The prevalence and evolution of BLMM in HER2-low mBC are similar to those in patients with HER2- tumors. In contrast to patients with HER2+ mBC, the prognosis of BLMM remains dismal in this population.

Enhanced expression of the PDGFR/Abl signaling pathway in aromatase inhibitor-resistant breast cancer.

BACKGROUND: We have found that the platelet-derived growth factor receptor (PDGFR)/Abl signaling pathway is up-regulated as a determinant of the acquisition of resistance to estrogen deprivation in vitro. We aimed to determine its clinical relevance in aromatase inhibitor (AI)-resistant breast cancer. PATIENTS AND METHODS: We identified a cohort of 45 patients with estrogen receptor-positive breast cancer who had been treated with an AI, subsequently relapsed and had biopsy material available from both the presentation and post-AI recurrent lesion. PDGFRα, PDGFRß and Abl expression was assessed in formalin-fixed paraffin-embedded sections. RESULTS: Tumor protein expression of PDGFRα (1.39-fold, P=0.0065), PDGFRß (4.32-fold, P=0.006) and Abl (1.8-fold, P=0.001) was increased at the point of relapse. Tumor and stromal expression of PDGFRα as well as PDGFRß was significantly correlated in pre-treatment and relapse samples. High post-treatment tumor and stromal PDGFRß levels were associated with a short time to treatment failure (TTF). Expression of PDGFRα in relapsing tumor specimens was correlated with Abl expression and Ki67 levels. Furthermore, changes in Abl correlated significantly with changes in ER expression. CONCLUSIONS: These clinical data support a role for enhanced PDGF/Abl signaling in AI-resistant disease and provide a rationale for targeting the pathway in endocrine-resistant breast cancer.

Association between the nuclear to cytoplasmic ratio of p27 and the efficacy of adjuvant polychemotherapy in early breast cancer.

BACKGROUND: The purpose of this study was to evaluate the prognostic and predictive value of p27 expression in patients with early breast cancer. PATIENTS AND METHODS: Quantitative immunofluorescence assays for p27 were done on a tissue microarray that included 823 samples from patients randomized between anthracycline-based chemotherapy and no chemotherapy. Quantification of p27 was done using the AQUA® system (HistoRx, Inc., Branford, CT). Both p27 nuclear expression and the nuclear to cytoplasmic ratio were assessed. RESULTS: Nuclear p27 expression was not predictive for the efficacy of anthracycline-based chemotherapy [adjusted P=0.18 for disease-free survival (DFS)] nor prognostic [95% confidence interval (CI) 0.99-1.01, P=0.49]. However, p27 nuclear/cytoplasmic ratio was predictive for the efficacy of adjuvant chemotherapy (adjusted P=0.016 DFS). The adjusted hazard ratio (HR) for relapse associated with adjuvant chemotherapy was 0.56 (95% CI 0.37-0.84, P=0.005) and 1.06 (95% CI 0.76-1.47, P=0.74) for patients with high and low nuclear/cytoplasmic ratio, respectively. p27 N/C ratio was prognostic in patients treated with chemotherapy (HR for relapse or death for a 1 unit increase in p27 N/C ratio was 0.30, 95% CI 0.12-0.77) but not in the untreated arm (HR for relapse or death was 1.27, 95% CI 0.58-2.8). CONCLUSIONS: This study did not confirm the role of p27 nuclear expression as a prognostic parameter. However, the p27 nuclear/cytoplasmic ratio was predictive in patients treated with anthracycline-based chemotherapy.

Breast Cancer Index predicts pathological complete response and eligibility for breast conserving surgery in breast cancer patients treated with neoadjuvant chemotherapy.

BACKGROUND: The aim of neoadjuvant chemotherapy is to increase the likelihood of successful breast conservation surgery (BCS). Accurate identification of BCS candidates is a diagnostic challenge. Breast Cancer Index (BCI) predicts recurrence risk in estrogen receptor+lymph node-breast cancer. Performance of BCI to predict chemosensitivity based on pathological complete response (pCR) and BCS was assessed. METHODS: Real-time RT-PCR BCI assay was conducted using tumor samples from 150 breast cancer patients treated with neoadjuvant chemotherapy. Logistical regression and c-index were used to assess predictive strength and additive accuracy of BCI beyond clinicopathologic factors. RESULTS: BCI classified 42% of patients as low, 35% as intermediate and 23% as high risk. Low BCI risk group had 98.4% negative predictive value (NPV) for pCR and 86% NPV for BCS. High versus low BCI group had a 34 and 5.8 greater likelihood of achieving pCR and BCS, respectively (P=0.0055; P=0.0022). BCI increased c-index for pCR (0.875-0.924; P=0.017) and BCS prediction (0.788-0.843; P=0.027) beyond clinicopathologic factors. CONCLUSIONS: BCI significantly predicted pCR and BCS beyond clinicopathologic factors. High NPVs indicate that BCI could be a useful tool to identify breast cancer patients who are not eligible for neoadjuvant chemotherapy. These results suggest that BCI could be used to assess both chemosensitivity and eligibility for BCS.

An immunological signature to predict outcome in patients with triple-negative breast cancer with residual disease after neoadjuvant chemotherapy.

BACKGROUND: When triple-negative breast cancer (TNBC) patients have residual disease after neoadjuvant chemotherapy (NACT), they have a high risk of metastatic relapse. With immune infiltrate in TNBC being prognostic and predictive of response to treatment, our aim was to develop an immunologic transcriptomic signature using post-NACT samples to predict relapse. MATERIALS AND METHODS: We identified 115 samples of residual tumors from post-NACT TNBC patients. We profiled the expression of 770 genes related to cancer microenvironment using the NanoString PanCancer IO360 panel to develop a prognostic transcriptomic signature, and we describe the immune microenvironments of the residual tumors. RESULTS: Thirty-eight (33%) patients experienced metastatic relapse. Hierarchical clustering separated patients into five clusters with distinct prognosis based on pathways linked to immune activation, epithelial-to-mesenchymal transition and cell cycle. The immune microenvironment of the residual disease was significantly different between patients who experienced relapse compared to those who did not, the latter having significantly more effector antitumoral immune cells, with significant differences in lymphoid subpopulations. We selected eight genes linked to immunity (BLK, GZMM, CXCR6, LILRA1, SPIB, CCL4, CXCR4, SLAMF7) to develop a transcriptomic signature which could predict relapse in our cohort. This signature was validated in two external cohorts (KMplot and METABRIC). CONCLUSIONS: Lack of immune activation after NACT is associated with a high risk of distant relapse. We propose a prognostic signature based on immune infiltrate that could lead to targeted therapeutic strategies to improve patient prognosis.

Discordance between core needle biopsy (CNB) and excisional biopsy (EB) for estrogen receptor (ER), progesterone receptor (PgR) and HER2 status in early breast cancer (EBC).

BACKGROUND: Analysis of estrogen receptor (ER), progesterone receptor (PgR) and HER2 status in early breast cancer (EBC) is increasingly being conducted in core needle biopsies (CNBs) taken at diagnosis but the concordance with the excisional biopsy (EB) is poorly documented. PATIENTS AND METHODS: Patients with EBC presenting to The Royal Marsden Hospital from June 2005 to September 2007 who had CNB and subsequent EB were included. ER and PgR were determined by immunohistochemistry (IHC) and graded from 0 to 8 (Allred score). HER2 was determined by IHC and scored from 0 to 3+. FISH analysis was carried out in HER2 2+ cases and in discordant cases. RESULTS: In all, 336 pairs of samples were compared. ER was positive in 253 CNBs (75%) for 255 EBs (76%) and was discordant in six patients (1.8%). PgR was positive in 221 CNBs (66%) and 227 (67.6%) EBs being discordant in 52 cases (15%). HER2 was positive in 41 (12.4%) of the 331 CNBs in which it was determined compared with 44 (13.3%) EBs and discordant in four cases (1.2%). CONCLUSIONS: CNB can be used with confidence for ER and HER2 determination. For PgR, due to a substantial discordance between CNB and EB, results from CNB should be used with caution.

Platinum-based chemotherapy in triple-negative breast cancer.

BACKGROUND: Experimental data suggest that triple-negative (TN) breast cancer may have increased sensitivity to platinum-based chemotherapy but clinical data are limited. We present our long-term results with platinum-based chemotherapy for TN breast cancer. PATIENTS AND METHODS: In all, 94 (17 TN), 79 (11 TN) and 155 (34 TN) patients receiving platinum-based chemotherapy in neo-adjuvant/adjuvant and advanced setting were included. Response rates and outcome were compared for TN tumours versus others. RESULTS: Neo-adjuvant complete response rates were significantly higher for TN tumours (88%) than others (51%; P = 0.005). The 5-year overall survival (OS) for TN tumours following adjuvant/neo-adjuvant chemotherapy was 64% [95% confidence interval (CI) 44% to 79%] compared with 85% (95% CI 79% to 90%) for others. Five-year disease-free survival for TN tumours was 57% (95% CI 37% to 73%) compared with 72% (95% CI 64% to 78%) for others. For patients with advanced breast cancer, overall response rates were 41% for TN tumours and 31% for others (P = 0.3). Patients with TN tumours had a significantly prolonged progression-free survival of 6 months compared with 4 months for others (P = 0.05), though the OS was not significantly different between the two groups (11 versus 7 months). CONCLUSION: Platinum-based chemotherapy achieves increased response rates for TN tumours, with a trend towards worse survival in early breast cancer through an improved survival in advanced disease. Prospective randomised trials are warranted.

[Conformal accelerated partial breast irradiation: state of the art]. / Irradiation partielle accélérée conformationnelle du sein : état des lieux.

Breast conserving treatment (breast conserving surgery followed by whole breast irradiation) has commonly been used in early breast cancer since many years. New radiation modalities have been recently developed in early breast cancers, particularly accelerated partial breast irradiation. Three-dimensional conformal accelerated partial breast irradiation is the most commonly used modality of radiotherapy. Other techniques are currently being developed, such as intensity-modulated radiotherapy, arctherapy, and tomotherapy. The present article reviews the indications, treatment modalities and side effects of accelerated partial breast irradiation.

Array CGH and PIK3CA/AKT1 mutations to drive patients to specific targeted agents: a clinical experience in 108 patients with metastatic breast cancer.

Breast cancer includes high number of molecular entities targetable by specific agents. In this study, array CGH and PIK3CA/AKT1 mutations were used to drive patients into targeted therapy. A prospective molecular analysis was offered to metastatic breast cancer patients for whom samples were collected prospectively or retrospectively either from frozen or paraffin-embedded tissue. Analyses were performed using array CGH (Agilent platform) and PIK3CA (exon 10 and 21) and AKT1 mutations were explored by standard Sanger sequencing. One hundred and eight patients were included. Good quality CGH was obtained in 79% cases and was better for frozen samples. Genomic alterations were identified in 50% of patients including 11 PIK3CA and 8 AKT1 mutations. Eighteen treatments (17 patients) were administered according to their molecular profile with evidence of activity in nine. Reasons for not providing a genomic-driven treatment included absence of progressive disease (38%), investigator's choice (9%), rapid PD (19%), and no drug access (21%). Array CGH correctly identified Her2 status in 97% cases; failures were related to low % of tumour cells. Our study showed that array CGH is feasible in the context of daily practice and, in combination with PIK3CA/AKT1 mutations, identifies a significant number of actionable molecular alterations that allow driving patients into specific targeted agents.