Mosaic BRCA1 promoter methylation contribution in hereditary breast/ovarian cancer pedigrees

PURPOSE

Mosaic BRCA1 promoter methylation (BRCA1meth) increases the risk of early-onset breast cancer, triple-negative breast cancer and ovarian cancer. As mosaic BRCA1meth are believed to occur de novo, their role in family breast/ovarian cancer has not been assessed.

PATIENTS

Blood-derived DNA from 20 unrelated affected cases from families with aggregation of breast/ovarian cancer, but with no germline pathogenic variants in BRCA1/2, PALB2 or RAD51C/D, were screened by methylation-sensitive high-resolution melting. CpG analysis was performed by pyrosequencing on blood and buccal swab. Two probands carried a pathogenic variant in a moderate-penetrance gene (ATM and BARD1), and 8 of 18 others (44%) carried BRCA1meth (vs none of the 20 age-matched controls). Involvement of BRCA1 in tumourigenesis in methylated probands was demonstrated in most tested cases by detection of a loss of heterozygosity and a homologous recombination deficiency signature. Among the eight methylated probands, two had relatives with breast cancer with detectable BRCA1meth in blood, including one with high methylation levels in two non-tumour tissues.

CONCLUSIONS

The high prevalence of mosaic BRCA1meth in patients with breast/ovarian cancer with affected relatives, as well as this first description of a family aggregation of mosaic BRCA1meth, shows how this de novo event can contribute to hereditary breast/ovarian cancer pedigrees.

Residual ANTXR1+ myofibroblasts after chemotherapy inhibit anti-tumor immunity via YAP1 signaling pathway

Although cancer-associated fibroblast (CAF) heterogeneity is well-established, the impact of chemotherapy on CAF populations remains poorly understood. Here we address this question in high-grade serous ovarian cancer (HGSOC), in which we previously identified 4 CAF populations. While the global content in stroma increases in HGSOC after chemotherapy, the proportion of FAP+ CAF (also called CAF-S1) decreases. Still, maintenance of high residual CAF-S1 content after chemotherapy is associated with reduced CD8+ T lymphocyte density and poor patient prognosis, emphasizing the importance of CAF-S1 reduction upon treatment. Single cell analysis, spatial transcriptomics and immunohistochemistry reveal that the content in the ECM-producing ANTXR1+ CAF-S1 cluster (ECM-myCAF) is the most affected by chemotherapy. Moreover, functional assays demonstrate that ECM-myCAF isolated from HGSOC reduce CD8+ T-cell cytotoxicity through a Yes Associated Protein 1 (YAP1)-dependent mechanism. Thus, efficient inhibition after treatment of YAP1-signaling pathway in the ECM-myCAF cluster could enhance CD8+ T-cell cytotoxicity. Altogether, these data pave the way for therapy targeting YAP1 in ECM-myCAF in HGSOC.

Adaptive nanopore sequencing to determine pathogenicity of BRCA1 exonic duplication

BRCA1 and BRCA2 are tumour suppressor genes that have been characterised as predisposition genes for the development of hereditary breast and ovarian cancers among other malignancies. The molecular diagnosis of this predisposition syndrome is based on the detection of inactivating variants of any type in those genes. But in the case of structural variants, functional consequences can be difficult to assess using standard molecular methods, as the precise resolution of their sequence is often impossible with short-read next generation sequencing techniques. It has been recently demonstrated that Oxford Nanopore long-read sequencing technology can accurately and rapidly provide genetic diagnoses of Mendelian diseases, including those linked to pathogenic structural variants. Here, we report the accurate resolution of a germline duplication event of exons 18-20 of BRCA1 using Nanopore sequencing with adaptive sampling target enrichment. This allowed us to classify this variant as pathogenic within a short timeframe of 10 days. This study provides a proof-of-concept that nanopore adaptive sampling is a highly efficient technique for the investigation of structural variants of tumour suppressor genes in a clinical context.

APC germline pathogenic variants and epithelial ovarian cancer: causal or coincidental findings?

APC germline pathogenic variants result in predisposition to familial adenomatous polyposis and extraintestinal tumours such as desmoid fibromatosis, medulloblastomas and thyroid cancers. They have also been recently involved in ovarian microcystic stromal tumours. APC inactivation has been described at the tumour level in epithelial ovarian cancers (EOCs). Here, we report the identification of APC germline pathogenic variants in two patients diagnosed with premenopausal EOC in early 30s, with no other pathogenic variant detected in the known ovarian cancer predisposing genes. Subsequent tumour analysis showed neither a second hit of APC inactivation nor β-catenin activation. Both tumours did not have a homologous recombination (HR) deficiency, pointing towards the implication of other genes than those involved in HR. APC may contribute to the carcinogenesis of EOC in a multifactorial context. Further studies are required to clarify the role of APC in predisposition to EOC.

A catalog of numerical centrosome defects in epithelial ovarian cancers

Centrosome amplification, the presence of more than two centrosomes in a cell is a common feature of most human cancer cell lines. However, little is known about centrosome numbers in human cancers and whether amplification or other numerical aberrations are frequently present. To address this question, we have analyzed a large cohort of primary human epithelial ovarian cancers (EOCs) from 100 patients. We found that rigorous quantitation of centrosome number in tumor samples was extremely challenging due to tumor heterogeneity and extensive tissue disorganization. Interestingly, even if centrosome clusters could be identified, the incidence of centrosome amplification was not comparable to what has been described in cultured cancer cells. Surprisingly, centrosome loss events where a few or many nuclei were not associated with centrosomes were clearly noticed and overall more frequent than centrosome amplification. Our findings highlight the difficulty of characterizing centrosome numbers in human tumors, while revealing a novel paradigm of centrosome number defects in EOCs.

[2021 update of the GEFPICS' recommendations for HER2 status assessment in invasive breast cancer in France]

The last international guidelines on HER2 determination in breast cancer have been updated in 2018 by the American Society of Clinical Oncology and College of American Pathologists, on the basis of a twenty-year practice and results of numerous clinical trials. Moreover, the emerging HER2-low concept for 1+ and 2+ non amplified breast cancers lead to refine French practices for HER2 status assessment. The GEFPICS group, composed of expert pathologists, herein presents the latest French recommendations for HER2 status evaluation in breast cancer, taking into account the ASCO/CAP guidelines and introducing the HER2-low concept. In the era of personalized medicine, HER2 status assessment remains one of the most important biomarkers in breast cancer and its quality guaranties the optimal patients' care. French pathologists' commitment in theranostic biomarker quality is more than ever required to provide the most efficient cares in oncology.

Co-occurrence of germline BRCA1 and CDH1 pathogenic variants

INTRODUCTION

We report a very rare case of familial breast cancer and diffuse gastric cancer, with germline pathogenic variants in both BRCA1 and CDH1 genes. To the best of our knowledge, this is the first report of such an association.Family description: The proband is a woman diagnosed with breast cancer at the age of 52 years. She requested genetic counselling in 2012, at the age of 91 years, because of a history of breast cancer in her daughter, her sister, her niece and her paternal grandmother and was therefore concerned about her relatives. Her sister and maternal aunt also had gastric cancer. She was tested for several genes associated with hereditary breast cancer.

RESULTS

A large deletion of BRCA1 from exons 1 to 7 and two CDH1 pathogenic cis variants were identified.

CONCLUSION

This complex situation is challenging for genetic counselling and management of at-risk individuals.

Molecular profiling of hormone receptor-positive, HER2-negative breast cancers from patients treated with neoadjuvant endocrine therapy in the CARMINA 02 trial (UCBG-0609)

BACKGROUND

Postmenopausal women with large, hormone receptor (HR)-positive/HER2-negative and low-proliferative breast cancer derived a benefit from neoadjuvant endocrine therapy (NET) in the CARMINA02 trial. This study was designed to correlate gene expression and mutation profiles with both response to NET and prognosis.

METHODS

Gene expression profiling using RNA sequencing was performed in 86 pre-NET and post-NET tumor samples. Targeted next-generation sequencing of 91 candidate breast cancer-associated genes was performed on DNA samples from 89 patients. Molecular data were correlated with radiological response and relapse-free survival.

RESULTS

The transcriptional profile of tumors to NET in responders involved immune-associated genes enriched in activated Th1 pathway, which remained unchanged in non-responders. Immune response was confirmed by analysis of tumor-infiltrating lymphocytes (TILs). The percentage of TILs was significantly increased post-NET compared to pre-NET samples in responders (p = 0.0071), but not in non-responders (p = 0.0938). Gene expression revealed that lipid metabolism was the main molecular function related to prognosis, while PPARγ is the most important upstream regulator gene. The most frequently mutated genes were PIK3CA (48.3%), CDH1 (20.2%), PTEN (15.7%), TP53 (10.1%), LAMA2 (10.1%), BRCA2 (9.0%), MAP3K1 (7.9%), ALK (6.7%), INPP4B (6.7%), NCOR1 (6.7%), and NF1 (5.6%). Cell cycle and apoptosis pathway and PIK3CA/AKT/mTOR pathway were altered significantly more frequently in non-responders than in responders (p = 0.0017 and p = 0.0094, respectively). The average number of mutations per sample was significantly higher in endocrine-resistant tumors (2.88 vs. 1.64, p = 0.03), but no difference was observed in terms of prognosis. ESR1 hotspot mutations were detected in 3.4% of treatment-naive tumors.

CONCLUSIONS

The Th1-related immune system and lipid metabolism appear to play key roles in the response to endocrine therapy and prognosis in HR-positive/HER2-negative breast cancer. Deleterious somatic mutations in the cell cycle and apoptosis pathway and PIK3CA/AKT/mTOR pathway may be relevant for clinical management.

TRIAL REGISTRATION

This trial is registered with ClinicalTrials.gov ( NCT00629616 ) on March 6, 2008, retrospectively registered.

The iron chelator deferasirox synergises with chemotherapy to treat triple-negative breast cancers

To ensure their high proliferation rate, tumor cells have an iron metabolic disorder causing them to have increased iron needs, making them more susceptible to iron deprivation. This vulnerability could be a therapeutic target. In breast cancers, the development of new therapeutic approaches is urgently needed for patients with triple-negative tumors, which frequently relapse after chemotherapy and suffer from a lack of targeted therapies. In this study, we demonstrated that deferasirox (DFX) synergises with standard chemotherapeutic agents such as doxorubicin, cisplatin and carboplatin to inhibit cell proliferation and induce apoptosis and autophagy in triple-negative breast cancer (TNBC) cells. Moreover, the combination of DFX with doxorubicin and cyclophosphamide delayed recurrences in breast cancer patient-derived xenografts without increasing the side-effects of chemotherapies alone or altering the global iron storage of mice. Antitumor synergy of DFX and doxorubicin seems to involve downregulation of the phosphoinositide 3-kinase and nuclear factor-κB pathways. Iron deprivation in combination with chemotherapy could thus help to improve the effectiveness of chemotherapy in TNBC patients without increasing toxicity. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Combination of COX-2 expression and PIK3CA mutation as prognostic and predictive markers for celecoxib treatment in breast cancer

COX-2 expression level and prognostic value are still a matter of debate in breast cancer (BC). We addressed these points in the context of PIK3CA mutational status. Based on an interesting study of aspirin efficacy in colorectal cancer, we hypothesized that celecoxib antitumoral activity may be restricted to PIK3CA mutated BC.

COX-2 mRNA expression was analyzed in 446 BC samples and in 61 BC patient-derived xenografts (PDX) using quantitative RT-PCR. The prognostic impact of COX-2 expression level was assessed independently and according to PIK3CA mutational status in our cohort and in a validation set of 817 BC. The antitumoral activity of celecoxib was tested in two triple-negative (TN) PDX with a PIK3CA wild-type (wt) or mutated genotype.

COX-2 mRNA was overexpressed in 2% of BC and significantly associated with TN subtype. Metastasis-free survival (MFS) was significantly better in patients with high COX-2 expression level, the prognosis of whom was similar to patients with PIK3CA mutations. TCGA validation cohort confirmed that patients with low COX-2 expression PIK3CA wt tumors had the worse disease-free survival (DFS) compared to all other subgroups. Celecoxib had a significant antitumoral effect in PIK3CA mutated PDX only. Celecoxib antitumoral activity involved S6 ribosomal protein and AKT phosphorylation.

Low expression of COX-2 has a significant negative impact on the MFS/DFS of BC patients. Antitumoral effect of celecoxib is restricted to PIK3CA mutated PDX. These results suggest that PIK3CA mutation may be a new predictive biomarker for celecoxib efficacy.

Abstract P2-03-04: Lymphovascular invasion in breast carcinoma following neodjuvant chemotherapy is a strong prognosis factor

Purpose : Lymphovascular invasion (LVI) is a poor prognosis factor in breast cancer (BC), but data on its value in the neoadjuvant setting is scarce. This study evaluates the relationships between post-NAC LVI and prognosis in BC.

Methods: We identified 1197 patients with primary BC receiving NAC +/- trastuzumab between 2002 and 2011. Information on LVI in post-NAC surgical specimen was retrieved from review of medical charts. Univariate and multivariate analyses were performed to assess the association of clinical, pathological factors with disease free survival (DFS) and overall survival (OS) was assessed using a cox proportional hazard model.

Results: On 1197 tumors, 528 were luminal (44.1%), 375 were triple negative breast cancer (TNBC) (31.3%) and 294 were HER2-positive (24.6%). On post-NAC surgical specimens, LVI was present in 302 (25.2%), absent in 531 (44.4%), and was not mentionned in 364 cases (30.4%). The presence of post-NAC LVI was associated with an impaired DFS (HR=2.17, 95 CI [1.65 - 2.86], p<0.001) and the magnitude of this impact varied by BC subtype (p-value for interaction=0.02), (luminal BC: HR=1.75, p=0.006; TNBC : HR=2.77, p<0.001 ; HER2-positive BC : HR=5.12, p<0.001).

Table 1 Univariate analysis and multivariate analysis on DFS (whole population)   Univariate  Multivariate VariableClassHRClpHRCIpAge< 451 0.35    45-550.82[0.62 - 1.08]     >550.87[0.64 - 1.19]    Menopausal statuspremenopausal1.04[0.81 - 1.34]0.75    postmenopausal1     BMI class19-251      < 191.24[0.75 - 2.05]0.41    > 251.36[1.06 - 1.75]0.01   Tumor sizeT1-T21      T31.77[1.38 - 2.27]<0.011.77[ 1.32 - 2.38 ]<0.001Clinical nodal statusN01      N1-N2-N31.35[1.05 - 1.72]0.021.43[ 1.07 - 1.91 ]0.016HistologyDuctal1      Other1.24[0.87 - 1.78]0.24   GradeGrade I-II1      III1.24[0.87 - 1.78]0.07   Ki 67<201      >201.54[1.06 - 2.22]0.02   Mitotic index≤221      >221.18[0.9 - 1.53]0.23   DCIS componentno1      yes1.33[0.88 - 2.01]0.18   Pre-NAC LVIno1      yes1.35[0.88 - 2.01]0.09   ER statusnegative1      positive0.72[0.56 - 0.91]<0.01   PR statusnegative1      positive0.66[0.51 - 0.85]<0.01   HER2 statusnegative1      positive0.84[0.62 - 1.14]0.26   BC subtypeluminal1      TNBC1.53[1.17 - 2]<0.012.67[ 1.93 - 3.69 ]<0.001 HER20.99[0.72 - 1.38]0.971.25[ 0.82 - 1.88 ]0.299Post NAC parametersPost-NAC LVI (breast)no1      yes2.17[1.65 - 2.86]<0.012.3[ 1.72 - 3.08 ]<0.001pCRNo pCR1      pCR0,4[0.27 - 0.59]<0.01   Pathological nodal involvement0       1-31.48[1.11 - 1.97]<0.01    ≥4 N+3.13[2.34 - 4.19]<0.01   RCB class01      10.97[0.36 - 2.64]0.96    22.88[1.69 - 4.89]<0.01    35.21[3.01 - 9.02]<0.01   ER: oestrogene receptor PR: progesteron receptor RCB: residual cancer burden

Post-NAC LVI was an independent predictor of poor DFS, that overwhelmed the prognostic impact of pathological complete response in all 3 BC subtypes. Post-NAC LVI was also an independent predictor of poor OS in the whole cohort and in all BC subtypes.

Table 1 resumes univariate and multivariate analysis on DFS in whole population.

Conclusion: Post-NAC LVI is a strong independent prognostic factor associated with poor DFS and OS, that (i) should be systematically mentioned in pathological reports following NAC and (ii) could be used to select high risk patients candidates to second line trials in the post-neoadjuvant window.

Citation Format: Hamy-Petit A-S, Lam G-T, Laas E, Darrigues L, Balezeau T, Guerin J, Livartowski A, Sadacca B, Pierga J-Y, Vincent-Salomon A, Bidard F-C, Lerebours F, Brain E, Becette V, Rouzier R, Lae M, Reyal F. Lymphovascular invasion in breast carcinoma following neodjuvant chemotherapy is a strong prognosis factor [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-03-04.

Limited Prognostic Value of c-erbB-2 Compared to uPA and PAI-1 in Primary Breast Carcinoma

In a retrospective study of 488 women with primary breast cancer, after a median follow-up of 10 years, we sought interactions between disease-free survival (DFS) and overall survival (OS) and tumor antigen levels of two components of the plasminogen system, urokinase-type plasminogen activator (uPA) and its inhibitor PAI-1, and the transmembrane growth factor receptor c-erbB-2. We used ELISAs (American Diagnostica, Greenwich, CT, USA) to quantify uPA and PAI-1 antigen levels in cytosols, and a double monoclonal antibody-based assay (EIA) (Ciba Corning Diagnostics, Alameda, CA, USA) to quantify c-erbB-2 in membrane extracts of the same tissues. Weak positive correlations were found between uPA and c-erbB-2 (rs=0.146; p=0.001) and between PAI-1 and c-erbB-2 (rs=0.154; p<0.001). In the overall population, using univariate analyses, c-erbB-2 overexpression and high uPA and PAI-1 antigen levels (>300 IU/mg, >1.40 ng/mg and >5.53 ng/mg, respectively) were significantly associated with shorter DFS (p=0.003, p<0.001 and p<0.001, respectively) and OS (p<0.001 in all cases). Using multivariate analyses, PAI-1, node status and tumor size were independent predictors of DFS and c-erbB-2 was retained in the model only for OS. In the node-negative subgroup, PAI-1 was the strongest significant survival predictor both for OS (p=0.003; HR 2.52) and DFS (p<0.001; HR 2.39). This study shows that in primary breast cancer c-erbB-2 offers no additional prognostic information when uPA and/or PAI-1 are candidates in the multivariate analyses.

Abstract 2031: Antitumoral synergy of iron chelators and chemotherapies in triple-negative breast cancer cell lines and patient-derived xenograft

Introduction: Tumor cells present an iron metabolic disorder with high proliferation rate, increased iron storage (ferritin and Labile Iron Pool - LIP) and high sensibility to iron deprivation, which could be a therapeutic target. Anticancer effect of iron chelators deferoxamine (DFO) and deferasirox (DFX) has been revealed in several types of cancers. In breast cancer (BC), the development of new therapeutic approaches is urgently needed for triple negative (TN) subtype which presents poor prognosis and lacks targeting therapy. We investigated the therapeutic potential of iron chelators combined with chemotherapeutic agents in TNBC cell lines and patient-derived xenografts (PDX).

Methods: Anticancer effects of iron chelators combined with chemotherapeutic agents (doxorubicin, cisplatin or carboplatin) were evaluated in vitro in 4 TNBC cell lines by MTT assay, annexin V/PI staining and assessment of caspase 3/7 activity. Assessment of LIP, transferrin receptor 1 (TfR1) expression level, Reactive Oxygen Species (ROS) production and mitochondrial membrane potential variations were performed by flow cytometry, and ELISA assay for ferritin level. The activity of DFX alone or combined with doxorubicin/cyclophosphamide (AC) was tested in the HBCx-10 TNBC PDX selected because of its relapse to AC. Iron homeostasis, hypoxia and PI3K pathway were analyzed by immunohistochemistry (IHC) and Western-blot in both cell lines and PDX tumors. In DFX+/-AC treated and untreated tumors, induction of apoptosis was performed by TUNEL assay and a transcriptome analysis is ongoing.

Results: Iron chelators acted in synergy effect with three chemotherapies in all cell lines which were tested to inhibit cell proliferation and induce apoptosis. Chelators increased cytotoxicity until 60% compared to chemotherapies alone. In all cell lines, chelators treatment increased TfR1 expression level and decreased LIP and ferritin. Furthermore, down-regulation of PI3K pathway, hypoxia, mitochondrial membrane potential, and the production increasing of ROS were observed. In HBCx-10 PDX, a trend for antitumoral activity of DFX alone was observed (p=0.09) at the end of the experiment (day 81). A significant difference of Relative Tumor Volume (RTV) was observed since day 18 between the AC group and the DFX+AC group (tumor growth inhibition: 37 to 61%, tumor growth delay: 10 to 14 days, 0.005&lt;p&lt;0.04). Same as the observing in vitro, modulations of PI3K pathway and hypoxia are involved in this antitumoral synergy. Except neutropenia (due to chemotherapy), no other hematologic toxicity was observed in both AC and DFX+AC groups.

Conclusions: Iron chelators may increase the effectiveness of conventional chemotherapies for TNBC treatments. This antitumoral synergy involves PI3K pathway downregulation, ROS production and decrease mitochondrial membrane potential.

Citation Format: Sandrine Tury, Sophie Vacher, Véronique Becette, Franck Assayag, Sophie Chateau-Joubert, Jean-Luc Servely, Elisabetta Marangoni, Ivan Bièche, Céline Callens. Antitumoral synergy of iron chelators and chemotherapies in triple-negative breast cancer cell lines and patient-derived xenograft [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2031. doi:10.1158/1538-7445.AM2017-2031

Abstract P4-01-03: Predictive value of FDG-PET/CT after neoadjuvant endocrine treatment in breast cancer

Background: Neaodjuvant endocrine therapy (NET) has demonstrated efficacy in terms of clinical response and outcome in hormone-receptor positive (HR+) post-menopausal patients (pts) with breast cancer (BC) not eligible for primary breast conservative surgery (BCS). However, the monitoring of tumor response to NET is challenging and clinical response is the current gold standard. The aim of the present study was to investigate the contribution of the early metabolic response (eMR) at one month in FDG-PET/CT in a NET setting for post-menopausal pts with HR+, HER2- BC compared to morphological and pathological responses. We also aimed to evaluate the prognostic value of eMR.

Methods: This was a prospective and ancillary study of CARMINA 02, UCBG0609 (Cancer in press), a phase II clinical trial evaluating the efficacy of 4 to 6 months neoadjuvant anastrozole or fulvestrant. FDG-PET/CT exams were performed at baseline (M0), after 1 month of treatment (M1: eMR) and pre-Op (late metabolic response: lMR) in 11 pts (74.2 years ± 3.6) from 2007 to 2010. Pts were classified “metabolic responders” (mR) if SUVmax values decrease was ≥ 40% at M1 and “non-metabolic responders” (mNR) if otherwise; lMR was also assessed in mR and mNR groups defined at M1. We compared eMR to morphological response (clinical, breast US and MRI) at M1 and pre-op, to the pathological response according to Sataloff classification and to Ki67 score variation during treatment. Early metabolic response was also correlated with the PEPI (Preoperative Endocrine Prognostic Index) score and survival (overall survival, OS and relapse free survival, RFS).

Results: Main results are summarized in Table I. There was a significant difference between mR and mNR pts at M1 (eMR) and pre-op (lMR). One patient with a complete metabolic response at pre-op had the best pathological response (Sataloff TB). Also, mR pts had a better clinical response: 2 partial response (PR) in mR vs 1 in mNR group and 2 mNR patients were classified PD (progressive disease). There was a trend toward better survival for mR pts in OS and RFS (Kaplan-Meier p=0.18 and 0.06, respectively) and all the pejorative events occurred in the mNR group: 3 deaths and 3 metastatic progressions. Besides, no difference in eMR was observed regarding the histological subtype (ductal or lobular; p&gt;0.05) nor the treatment group (p&gt;0.05).

Table I: Metabolic, morphological and pathological response at M1, Pre-Op and on the surgical specimen.  MR : 5ptsmNR : 6ptsP valueM1SUVmax2.6±1.13.9±1.40.00017 Clinical size42.5mm±11.951.7mm±7.50.19 US size22.6mm±6.334.2mm±2.40.02 MRI size21.2mm±4.239.7mm±4.79.16 E-5 Ki 673.6%±1.98.2%±80.19Pre-OpSUVmax2±1.33.3±1.40.018 Clinical size31mm±12.448.3mm±10.80.035 US size18.5mm±7.331.3mm±9.50.07 MRI size17.9mm±7.134.8mm±7.70.003Surgical SpecimenSataloff (TA+TB vs TC+TD)20% vs 80%0 vs 100%1 PEPI score (I+II vs III)80% vs 20%33 vs 67%0.048 Ki 678.6%±9.812.3%±7.90.41

Conclusions: These preliminary results showed the value of the early metabolic response in FDG- PET/CT in a NET setting compared to the morphological or the pathological responses alone. Early metabolic responders patients had better OS, RFS and PEPI scores.

Citation Format: Boughdad S, Champion L, Becette V, Cherel P, Fourme E, Edeline V, Lemonnier J, Lerebours F, Alberini JL. Predictive value of FDG-PET/CT after neoadjuvant endocrine treatment in breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-01-03.

Abstract P3-04-09: Genomic analysis to evaluate response to neoadjuvant anastrozole and fulvestrant in post-menopausal ER-positive HER2-negative breast cancer patients included in the UCBG CARMINA02 trial

Background: CARMINA02 is a non-comparative multicenter phase II randomized trial evaluating the clinical response rate after up to 6 months of neoadjuvant endocrine therapy (NET) in HR+/HER2- patients with 1 mg anastrozole (Arm A) or 500 mg fulvestrant (Arm B). Secondary objectives included predictive markers of response and outcome. Between 2007 and 2011, 116 women with operable infiltrating breast adenocarcinoma T2-T4 N0-N3 M0 were randomized. Clinical response rates at 6 months (RECIST criteria) were 52.6% [95%CI 41-64%] in Arm A and 36.8% [95%CI 25-49%] in Arm B (Cancer 2016, in press). We aimed to identify the molecular predictive markers of resistance or sensitivity common to both treatments.

Methods: Ninety tumor RNA from clinical responder (n=34) and resistant patients (n=23) treated in arms A or B have been sequenced with Illumina Hiseq2500 technology leading to 2x100-nt paired-end RNA-seq reads. These samples are from pre-treatment (29 in arm A, 28 in arm B) and post-treatment tumors (6 months after, 17 in arm A and 16 in arm B). Alignment was performed with Tophat_2.0.6. Differential gene expression was analyzed with the Differential Expression analysis for Sequence count data package. Gene fusion was detected with ChimeraScan, TophatFusion and DeFuse tools. Variant calling including variations, insertions and deletions was processed following GATK recommendations for RNAseq datas. Quantitative RT-PCR experiments were done to confirm RNA-seq expression results in patient samples not selected for RNA-seq analysis (validation cohort).

Results: We first analyzed differentially expressed genes (DEGs) between responders and non-responders in pre-treatment or post-treatment samples to select potential predictive markers of response. We identified 51 DEGs before treatment common to anastrozole and fulvestrant. Among these 51 genes, SGK2 was the only gene more intensely expressed in responders than in non-responders. Then we compared DEGs between pre and post-treatment samples for responders or non-reponders for both treatment arms. SGK2 expression remains stable after treatment. Furthermore we identified 7 DEGs specific to responders and 11 DEGs specific to non-responders. Concerning genes fusion detection predicted by at least 2 tools, none was specific to a response type. We noted a higher number of fusions in non-responders samples. Variants detected by RNA-Seq are being confirmed by DNA-Seq using a home-made next-generation sequencing panel including 95 genes frequently mutated in breast cancers (analysis ongoing).

Conclusion:High expression of SGK2, encoding a kinase induced in response to signals that activate PI3kinase, may represent a predictive marker of sensitivity to NET. DEGs associated with NET response or resistance belong to cell cycle, DNA replication and repair, cell death and drug metabolism. Ongoing DNA-seq datas will complete this genomic analysis. This research was conducted with support from AstraZeneca and Institut Curie.

Citation Format: Callens C, Bessoltane N, Ngo C, Chemlali W, Becette V, Bernard V, Delattre O, Lemonnier J, Mouret-Reynier M-A, Andre F, Bieche I, Lerebours F. Genomic analysis to evaluate response to neoadjuvant anastrozole and fulvestrant in post-menopausal ER-positive HER2-negative breast cancer patients included in the UCBG CARMINA02 trial [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-04-09.

Circulating human papillomavirus DNA detected using droplet digital PCR in the serum of patients diagnosed with early stage human papillomavirus-associated invasive carcinoma

Specific human papillomavirus genotypes are associated with most ano‐genital carcinomas and a large subset of oro‐pharyngeal carcinomas. Human papillomavirus DNA is thus a tumour marker that can be detected in the blood of patients for clinical monitoring. However, data concerning circulating human papillomavirus DNA in cervical cancer patients has provided little clinical value, due to insufficient sensitivity of the assays used for the detection of small sized tumours. Here we took advantage of the sensitive droplet digital PCR method to identify circulating human papillomavirus DNA in patients with human papillomavirus‐associated carcinomas.

A series of 70 serum specimens, taken at the time of diagnosis, between 2002 and 2013, were retrospectively analyzed in patients with human papillomavirus‐16 or human papillomavirus‐18‐associated carcinomas, composed of 47 cases from the uterine cervix, 15 from the anal canal and 8 from the oro‐pharynx. As negative controls, 18 serum samples from women with human papillomavirus‐16‐associated high‐grade cervical intraepithelial neoplasia were also analyzed. Serum samples were stored at −80°C (27 cases) or at −20°C (43 cases). DNA was isolated from 200 µl of serum or plasma and droplet digital PCR was performed using human papillomavirus‐16 E7 and human papillomavirus‐18 E7 specific primers.

Circulating human papillomavirus DNA was detected in 61/70 (87%) serum samples from patients with carcinoma and in no serum from patients with cervical intraepithelial neoplasia. The positivity rate increased to 93% when using only serum stored at −80°C. Importantly, the two patients with microinvasive carcinomas in this series were positive. Quantitative evaluation showed that circulating viral DNA levels in cervical cancer patients were related to the clinical stage and tumour size, ranging from 55 ± 85 copies/ml (stage I) to 1774 ± 3676 copies/ml (stage IV).

Circulating human papillomavirus DNA is present in patients with human papillomavirus‐associated invasive cancers even at sub‐clinical stages and its level is related to tumour dynamics. Droplet digital PCR is a promising method for circulating human papillomavirus DNA detection and quantification. No positivity was found in patients with human papillomavirus‐associated high grade cervical intraepithelial neoplasia.

Abstract P4-09-03: Prognostic and predictive value of COX2 in breast cancer, correlation with PIK3CA mutations

Background: Cyclooxygenase-2 (COX2) is responsible for the synthesis of prostaglandins from arachidonic acid. This enzyme is weakly expressed in normal tissues and implicated in oncogenic and inflammatory processes. Treatment with a COX2 inhibitor (aspirin) increases overall survival of patients with colorectal cancer only for PIK3CA mutated tumors confirming an interaction between COX2 and the PI3K/AKT pathway. PIK3CA gene mutations are detected in 10-40% of BC depending on the molecular subtype. We hypothesized that COX inhibition could have an impact in Breast Cancer (BC) treatment.

Methods: COX2 mRNA expression levels were analyzed in 446 BC samples and 61 patient-derived xenografts (PDX) using qRT-PCR. Protein expression of COX2 was studied by immunohistochemistry (IHC) in 26 BC and 14 PDX. The prognostic impact of COX2 expression level according to PIK3CA mutation status was also analyzed in BC patients. The activity of celecoxib, a selective COX2 inhibitor, was tested in two PDX of triple-negative BC: the HBCx50 PDX (PIK3CA wild-type, expressing COX2) and the HBCx4B PDX (PIK3CA mutated, expressing COX2).

Results: COX2 transcript was under-expressed in 74% and overexpressed in 2% of the BC samples. COX2 overexpression is significantly associated with triple-negative subtype (11%, 7/68 cases, p&lt;0.0001). Moreover, immunostaining of COX2 was well correlated with COX2 mRNA expression level. PIK3CA mutations were detected in 33% of patients. We showed that metastasis-free survival (MFS) was significantly better in patients who do not under-express COX2 (p=0.007) or in patients with PIK3CA mutation (p=0.02) regardless the BC subtype and adjuvant treatment. In the PIK3CA wild-type (wt) subgroup, MFS of patients was significantly better in patients not under-expressing COX2 than in patients under-expressing COX2 (p=0.01). In PDX, the strongest expression levels of COX2 were found in triple-negative (median 36 [0-1673]) compared to luminal (median 0 [0-202]) and HER2 positive subtypes (median 6 [0-601]). In vivo studies showed that celecoxib has no effect on the HBCx50 (PIK3CA wt) PDX growth while a significant antitumoral effect of celecoxib is observed in HBCx4B (PIK3CA mutated) PDX (tumor growth inhibition=41%, p=0.03).

Conclusion: In BC, COX2 underexpression is frequent and impact prognosis. BC overexpressing COX2 are rare and mainly belong to the triple-negative subtype. In vivo PDX studies show that the antitumoral effect of celecoxib may be restricted to BC expressing COX2 with PIK3CA mutation. Analyses of signaling pathways, expression levels of COX2 and its target proteins, tumor proliferation and apoptosis induction are ongoing on tumors and serum of mice to elucidate the antitumoral effect of celecoxib. This work could help to identify a subgroup of BC patients who may benefit from celecoxib especially as COX2 immunostaining and PIK3CA mutation status could routinely be used as COX2 inhibitor sensitivity biomarkers. These results need to be validated in a phase II clinical trial.

Citation Format: Tury S, Becette V, Assayag F, Vacher S, Marangoni E, Bièche I, Lerebours F, Callens C. Prognostic and predictive value of COX2 in breast cancer, correlation with PIK3CA mutations. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-09-03.

[Fertility sparing treatment in women affected by cervical cancer larger than 2cm]

OBJECTIVE

We report our experience on fertility sparing treatment in young women affected by cervical cancer of more than 2cm.

METHODS

Between July 2012 and February 2014, five patients presenting cervical tumors larger than 2cm (IB1>2cm) (23-35) and wishing to preserve fertility have been treated at our institution. Laparoscopic pelvic and para-aortic lymphadenectomy was performed for all patients. When lymph nodes were free of disease, patients had neoadjuvant chemotherapy followed by surgical conservative treatment.

RESULTS

Four patients underwent a cisplatin based neoadjuvant chemotherapy before conservative surgery: radical trachelectomy or simple trachelectomy. One patient with nodal involvement underwent a 3cycle chemotherapy followed by concurrent radiochemotherapy. Hematologic toxicity grade 3 was observed in one patient leading to a change of chemotherapy. Two patients showed complete disappearance of tumor and two a partial response to neoadjuvant treatment. After a mean follow up of 20.5months (14-33), no relapse was observed. To date, no pregnancy was obtained.

CONCLUSION

Lymph node staging followed by neoadjuvant chemotherapy and radical trachelectomy seems to be a promising treatment scheme for patients with cervical tumors IB1>2cm pN0 seeking parenthood.

Histo-genomic stratification reveals the frequent amplification/overexpression of CCNE1 and BRD4 genes in non-BRCAness high grade ovarian carcinoma

The treatment of epithelial ovarian cancer (EOC) is narrowly focused despite the heterogeneity of this disease in which outcomes remain poor. To stratify EOC patients for targeted therapy, we developed an approach integrating expression and genomic analyses including the BRCAness status. Gene expression and genomic profiling were used to identify genes recurrently (>5%) amplified and overexpressed in 105 EOC. The LST (Large-scale State Transition) genomic signature of BRCAness was applied to define molecular subgroups of EOC. Amplified/overexpressed genes clustered mainly in 3q, 8q, 19p and 19q. These changes were generally found mutually exclusive. In the 85 patients for which the genomic signature could be determined, genomic BRCAness was found in 52 cases (61.1%) and non-BRCAness in 33 (38.8%). A striking mutual exclusivity was observed between BRCAness and amplification/overexpression data. Whereas 3q and 8q alterations were preferentially observed in BRCAness EOC, most alterations on chromosome 19 were in non-BRCAness cases. CCNE1 (19q12) and BRD4 (19p13.1) amplification/overexpression was found in 19/33 (57.5%) of non-BRCAness cases. Such disequilibrium was also found in the TCGA EOC data set used for validation. Potential target genes are frequently amplified/overexpressed in non-BRCAness EOC. We report that BRD4, already identified as a target in several tumor models, is a new potential target in high grade non-BRCAness ovarian carcinoma.

P5-11-13: Rates of Upgrade to Malignancy for 271 Cases of Atypical Columnar Cell Hyperplasia Diagnosed by Breast Core Biopsy

Purpose: Atypical columnar cell hyperplasia (ACCH) is a borderline lesion that might represent an early stage in the development of certain low-grade carcinomas in situ (CIS) and invasive cancers. There are no guidelines on its management. Our objectives were to determine the upgrade to malignancy rate and identify a subpopulation of patients that might undergo just mammographic surveillance.

Methods: We retrospectively reviewed the data for 271 ACCH cases among 5555 breast core biopsies obtained over a 7-year period (Jan. 2003 — Jan. 2010). We collated clinical data (age, history of cancer, menopausal status), radiological data (lesion type, size, Bi-Rads category), technical data (number of biopsies, needle gauge, excision quality) and histological data and sought correlations between these factors and upgrade rate.

Results: The 271 ACCH comprised 128 cases of pure ACCH, 135 cases of ACCH + atypical ductal hyperplasia, and 8 cases of ACCH + atypical lobular hyperplasia. Overall, 184 patients underwent surgery and 46 mammographic surveillance. Surgery detected 34 cases of malignancy (23 CIS, 7 invasive cancers, and 4 mixed cases) giving a 15% upgrade rate. Quality of excision was the only factor associated with under-diagnosis.

Conclusion: The presence of ACCH at biopsy warrants surgery.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-11-13.

[The lesions of flat epithelial atypia diagnosed on breast biopsy]

Among pre-invasive breast diseases, the lesion of flat epithelial atypia has a level of risk that remains unclear. The clinical significance of these lesions and how to behave during their diagnostic biopsy (monitoring vs. surgery) are still uncertain, because few studies (including monitoring) are available and because of the polymorphic spectrum of lesions and their many denominations across the studies in the literature. This article aims to update our knowledge and provide elements for the management of these lesions diagnosed on breast biopsy.

TP53 status for prediction of sensitivity to taxane versus non-taxane neoadjuvant chemotherapy in breast cancer (EORTC 10994/BIG 1-00): a randomised phase 3 trial

BACKGROUND

TP53 has a crucial role in the DNA damage response. We therefore tested the hypothesis that taxanes confer a greater advantage than do anthracyclines on breast cancers with mutated TP53 than in those with wild-type TP53.

METHODS

In an open-label, phase 3 study, women (age <71 years) with locally advanced, inflammatory, or large operable breast cancers were randomly assigned in a 1:1 ratio to either a standard anthracycline regimen (six cycles of intravenous fluorouracil 500 mg/m², epirubicin 100 mg/m², and cyclophosphamide 500 mg/m² every 21 days [FEC100], or fluorouracil 600 mg/m², epirubicin 75 mg/m², cyclophosphamide 900 mg/m² [tailored FEC] starting on day 1 and then every 21 days) or a taxane-based regimen (three cycles of docetaxel 100 mg/m², intravenously infused over 1 h on day 1 every 21 days, followed by three cycles of intravenous epirubicin 90 mg/m² and docetaxel 75 mg/m² on day 1 every 21 days [T-ET]) at 42 centres in Europe. Randomisation was by use of a minimisation method that stratified patients by institution and initial tumour stage. The primary endpoint was progression-free survival (PFS) according to TP53 status. Analysis was by intention to treat. This is the final analysis of this trial. The study is registered with ClinicalTrials.gov, number NCT00017095.

FINDINGS

928 patients were enrolled in the FEC group and 928 in the T-ET group. TP53 status was not assessable for 183 (20%) patients in the FEC group and 204 (22%) patients in the T-ET group mainly because of low tumour-cell content in the biopsy. 361 primary endpoint events were recorded in the FEC group and 314 in the T-ET group. In patients with TP53-mutated tumours, 5-year PFS was 59·5% (95% CI 53·4-65·1) in the T-ET group (n=326) and 55·3% (49·2-60·9) in the FEC group (n=318; hazard ratio 0·84, 98% CI 0·63-1·14; p=0·17). In patients with TP53 wild-type tumours, 5-year PFS was 66·8% (95% CI 61·4-71·6) in the T-ET group (n=398) and 64·7% (59·6-69·4) in the FEC group (n=427; 0·89, 98% CI 0·68-1·18; p=0·35). For all patients, irrespective of TP53 status, 5-year PFS was 65·1% (95% CI 61·6-68·3) in the T-ET group and 60·8% (57·3-64·2) in the FEC group (0·85, 98% CI 0·71-1·02; p=0·035). At the sites using FEC100 versus T-ET, the most common grade 3 or 4 adverse events were febrile neutropenia (75 [9%] of 803 vs 173 [21%] of 809, respectively), and neutropenia (653 [81%] vs 730 [90%], respectively). At the sites using tailored FEC versus T-ET, the most common grade 3 or 4 adverse events were febrile neutropenia (ten [8%] of 118 vs 26 [22%] of 116, respectively), and neutropenia (100 [85%] vs 115 [99%], respectively). Two patients died of toxicity during or within 30 days of chemotherapy completion and without disease relapse (one in each group).

INTERPRETATION

Although TP53 status was prognostic for overall survival, it was not predictive of preferential sensitivity to taxanes. TP53 status tested by use of the yeast assay in this patient population cannot be used to select patients for an anthracycline-based chemotherapy versus a taxane-based chemotherapy.

FUNDING

US National Cancer Institute, La Ligue Nationale Contre le Cancer, European Union, Pharmacia, and Sanofi-Aventis.

Immunomarker studies of fine-needle cytopuncture cell blocks for tumor response prediction after preoperative chemotherapy and prognosis in operable nonmetastatic primary breast carcinoma

Neo-adjuvant chemotherapy of breast cancer provides an opportunity to evaluate predictive factors at initial tumor biopsy. We evaluated these factors on cell blocks obtained by diagnostic fine-needle cytopuncture (FNC), with respect to tumor regression and outcome. A prospective study (1996-2003, median follow-up 82 months) involved 163 patients with breast carcinoma (T2 ≥ 3 cm, T3, T4 noninflammatory) diagnosed by means of FNC. Malignancy, cytologic grade, and the presence of lymphocytes were determined on cytologic smears. Ki67, estrogen receptor (ER), progesterone receptor (PgR), HER2, and p53 expression was assessed on cell blocks by means of immunohistochemistry. All the patients received anthracycline-based chemotherapy. A combined clinical and pathologic tumor regression score was calculated. Twelve cases (7.5%) showed a complete regression, 72 cases (44%) a partial regression and 79 cases (48.5%) no regression. Factors predictive of regression were high grade, presence of lymphocytes, pN0, high Ki67 expression, hormone receptor negativity, and the "triple negative" phenotype. In univariate analysis 5-year metastasis-free survival rate (MFS) correlated with cytologic grade, pN, ER, and p53 status, while overall survival (OS) correlated with cytologic grade, type of surgery, pN, and ER status. In multivariate analysis, MFS was significantly influenced by the regression score, Ki67, age, ER status, pN, HER2, and initial tumor size. Except for age, the same parameters correlated with OS. FNC with the cell block technique is a rapid, minimally invasive, reliable, and inexpensive method for analyzing predictive biomarkers, and may thus be useful in the management of breast cancer patients requiring neo-adjuvant chemotherapy.

Phase III trial (EORTC 10994/BIG 00-01) assessing the value of p53 using a functional assay to predict sensitivity to a taxane versus nontaxane primary chemotherapy in breast cancer: Final analysis

LBA503

Background: Predictive markers of response to chemotherapy are lacking. Preclinical data suggest that p53 mutated tumors are resistant to anthracyclines and sensitive to taxanes. However, clinical data are contradictory. Using a functional yeast assay to detect biologically important mutations, this study tested the hypothesis that docetaxel confers a greater advantage over anthracyclines in p53 mutated tumors (mut) than p53 wild type (wt).

Methods: Patients (pts) with locally advanced/inflammatory or large operable tumors were randomized to either a standard anthracycline regimen (arm A) or a taxane-based treatment (arm B). In arm A pts received 6 cycles of FEC 100, or tailored FEC + G-CSF (Swedish cohort). In arm B docetaxel (T) 100mg/m2 was given for 3 cycles, followed by 3 cycles of epirubicin 90mg/m2and T 75mg/m2 q3 weeks (T-ET). After chemotherapy, pts underwent surgery followed by radiotherapy. Endocrine therapy and/or trastuzumab were given according to each center's policy. Fresh frozen tumor biopsies were mandatory before starting chemotherapy: frozen sections were examined centrally and the p53 test was done when the invasive tumor cell content was > 20%. cDNA derived from tumor-extracted RNA was transfected into yeast (Flaman et al. PNAS 1995): tumors were deemed p53 wt when there were < 20% red colonies (background) and p53 mut > 20%. The three co-primary comparisons for the endpoint of progression-free survival (PFS) were between arms A and B in p53 mut, p53 wt, and the entire trial population, each at a p=0.02. The sample size gave sufficient power for an interaction test for outcomes between p53 mut and wt at p<0.05.

Results: From April 2001 to November 2006, 1,856 patients were included. A total of 386 pts (21%) were ineligible (including 292 pts with <20% tumor cells and 67 without sample). No unexpected toxicity was observed. At the time of analysis 675 events were registered after a median follow-up time of 57 months. The results are summarized below.

Conclusions: p53 is not a predictive factor of response or resistance to taxanes, although it is, as expected, prognostic (<0.001). PFS is not statistically significantly different between FEC and T-ET arms at the 2% cutoff level.

[Table: see text]

[Table: see text]

P53 functional assay in yeast: evaluation in 1856 patients in a large prospective clinical trial (EORTC 10994/BIG 00-01)

Abstract #1067

Background:Although mutations in the p53 gene can occur in 20-30% of sporadic breast cancer, and are associated with other poor prognostic factors, there is no clear evidence as to whether p53 status should influence therapy. Immunohistochemistry has been demonstrated to be an inferior method compared with sequencing, but the optimal technique to assess the functional p53 status is not known. The yeast test is a functional assay which tests the transcriptional competence of p53, and detects biologically important mutations. Here we present the results of p53 evaluation using this method in a prospective study.&#x2028; Material and methods: EORTC 10994/BIG 00-01 trial is a randomized trial comparing the neoadjuvant use of an anthracycline-based regimen with a taxane-containing regimen in patients with large operable or locally advanced breast cancers. Fresh frozen tumour biopsies were mandatory before starting chemotherapy. Frozen sections were examined centrally and the p53 test was done if the invasive tumour cell content was above 20%. RNA extract was used to assess p53 status: p53 wild type tumours were defined as tumours whose cDNA transfected in yeast gave less than 20% red colonies (background); p53 mutated tumours gave 20% or more red colonies.&#x2028; Results: The trial accrual was completed in November 2006 after inclusion of 1856 patients. There was no frozen sample available in 70 patients. In 276 patients the % of tumour cells was &lt;20. The p53 test failed in 62 patients, generally because the quality or quantity of RNA was too low for RT-PCR. P53 was successfully assessed in 1458 patients: 661 (45%) tumours are p53 mutated and 797 (55%) are p53 wt. p53 mutated and wild type tumours were grade III in 40% (265/661) and 19% (153/797), respectively, and estrogen receptor negative in 41% (270/661) and 14.5% (116/797), respectively. We did not see any correlation between p53 status and tumour size or nodal status at diagnosis. HER2 status data are being collected.&#x2028; Conclusion: P53 status has been successfully evaluated using a yeast assay in 78.5% (1458/1856) of cases in the context of a multicenter trial. In indirect comparisons the frequency of patients with functionally altered p53 status is higher than with sequenced based methods. Our results confirm an association between p53 mutation and high grade or estrogen receptor negative status, but not with age, tumour size or clinical nodal status. More data regarding the quality and quantity of RNA collected will be presented at the meeting.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1067.

Cytologic diagnosis of lobular carcinoma of the breast: experience with 555 patients in the Rene Huguenin Cancer Center

BACKGROUND

Fine-needle aspiration generally produces results that are not as good for lobular carcinoma as the results for ductal carcinoma of the breast. In this study, the authors evaluated their team's performance in cytologic diagnosis of lobular carcinoma over 11 years and analyzed the reasons for diagnostic failure.

METHODS

Cytologic findings were analyzed in 555 consecutive fine-needle cytopuncture specimens from women with palpable, invasive lobular carcinoma of the breast. The authors also examined the influence of the cytologist's experience, the clinical tumor size, the histologic subtype, and the histologic grade on diagnostic performance. All negative samples were re-examined, along with all samples that had been obtained during the last year of the study, to refine the morphologic description of lobular carcinoma.

RESULTS

Malignancy was diagnosed in 68.8% of specimens overall. The individual pathologists diagnosed malignancy in from 44.4% to 81.1% of specimens, depending on their experience. Diagnostic performance was correlated with clinical tumor size, histologic grade, and histologic subtype, and correct diagnoses were significantly more frequent in pleomorphic subtypes than in "classic" types. Re-examination of all 32 negative specimens reduced the false-negative rate from 5.8% to 3.8%.

CONCLUSIONS

Despite the pitfalls associated with lobular carcinoma of the breast, fine-needle cytopuncture remains a useful diagnostic tool before treatment. Failures can be reduced through experience and by better knowledge of cytologic features.

Validation of gene signatures that predict the response of breast cancer to neoadjuvant chemotherapy: a substudy of the EORTC 10994/BIG 00-01 clinical trial

BACKGROUND

We have previously described gene-expression signatures that predict growth inhibitory and cytotoxic effects of common chemotherapeutic drugs in vitro. The aim of this study was to confirm the validity of these gene-expression signatures in a large series of patients with oestrogen-receptor-negative breast tumours who were treated in a phase III neoadjuvant clinical trial.

METHODS

This trial compares a non-taxane regimen (fluorouracil, epirubicin, and cyclophosphamide [FEC] for six cycles) with a taxane regimen (docetaxel for three cycles followed by epirubicin plus docetaxel [TET] for three cycles) in women with oestrogen-receptor-negative breast cancer. The primary endpoint of the study is the difference in progression-free survival based on TP53 status and will be reported later. Predicting response with gene signatures was a planned secondary endpoint of the trial and is reported here. Pathological complete response, defined as complete disappearance of the tumour with no more than a few scattered tumour cells detected by the pathologist in the resection specimen, was used to assess chemosensitivity. RNA was prepared from sections of frozen biopsies taken at diagnosis and hybridised to Affymetrix X3P microarrays. In-vitro single-agent drug sensitivity signatures were combined to obtain FEC and TET regimen-specific signatures. This study is registered on the clinical trials site of the US National Cancer Institute website http://www.clinicaltrials.gov/ct/show/NCT00017095.

FINDINGS

Of 212 patients with oestrogen-receptor-negative tumours assessed, 87 patients were excluded. 125 oestrogen-receptor-negative tumours (55 that showed pathological complete responses) were tested: 66 in the FEC group (28 that showed pathological complete responses) and 59 in the TET group (27 that showed pathological complete responses). The regimen-specific signatures significantly predicted pathological complete response in patients treated with the appropriate regimen (p<0.0001). The FEC predictor had a sensitivity of 96% (27 of 28 patients [95% CI 82-99]), specificity of 66% (25 of 38 patients [50-79]), positive predictive value (PPV) of 68% (27 of 40 patients [52-80]), and negative predictive value (NPV) of 96% (25 of 26 patients [81-99]). The TET predictor had a sensitivity of 93% (25 of 27 patients [77-98]), specificity 69% (22 of 32 patients [51-82]), PPV of 71% (25 of 35 patients [55-84]), and NPV of 92% (22 of 24 patients [74-98]). Analysis of tumour size, grade, nodal status, age, and regimen-specific signatures showed that the genomic signatures were the only independent variables predicting pathological complete response at p<0.01. Selection of patients with these signatures would increase the proportion of patients with pathological complete responses from 44% to around 70% in the patients studied here.

INTERPRETATION

We have validated the use of regimen-specific drug sensitivity signatures in the context of a multicentre randomised trial. The high NPV of both signatures may allow early selection of patients with breast cancer who should be considered for trials with new drugs.

Stellate images: anatomic and radiologic correlations

The stellate images are the most well-known and most typical finding in the diagnosis of breast cancer. Its positive predictive value is very high. However, in some cases, the stellate images can correspond to benign lesions. Stellate images require high quality mammograms, precise analysis, and as always in senology, confirmation by clinical examination, ultrasound if necessary, and in the case of palpable lesions, cytology. In this work, we will study malignant and benign stellate images mammographic-pathologic correlation as well as the importance of stellate images in the detection of non-palpable lesions. The typical stellate finding is correlated with the phenomena of fibrosis and elastosis and it is impossible to distinguish benign spicules from malignant spicules on mammography. We will present guidelines in the face of stellate image. Stellate images are for the most part suggestive of malignant lesions, and their discovery should lead to suspicion of cancer until the contrary is proven.

Use of radiology for the pathologist in the management of breast lesions

Today radiology is an essential step in the pathological analysis of breast biopsies. It is determinant at each stage of the management of non palpable lesions, clusters of microcalcifications and opacities, whether this concerns the needle biopsy or the surgical excision. Firstly, an X-ray is necessary to ensure that the core needle biopsy specimen has been adequately sampled and when samples with microcalcifications are selected by the radiologist, management can be more specific and accurate. In the case of surgical specimens, the X-ray confirms the presence of the radiographic abnormality or the clip indicating the site of the surgical excision which guides sampling. Some radiographic features also provide information on underlying pathologies allowing management to be adapted accordingly. Radiographs are also important to ensure that microscopically detected microcalcifications or lesions exactly correspond to the radiographic abnormality in size and location. The paraffin block can also be X-rayed to select those containing microcalcifications for additional slicing. It is also important to identify the presence of modifications caused by the core needle biopsy (fibrosis, haemorrhage and inflammation) and to carefully recognize displacement of epithelial cells and pseudo-emboli resulting from the needle procedure. Such correlation between radiology and pathology is essential so that appropriate management of the specimen can be adapted and to avoid pitfalls arising from pre-operative procedures.

Gene transcript assay by real-time RT-PCR in epithelial breast cancer cells selected by laser microdissection

The cell type heterogeneity within clinical cancer tissue samples may affect the accuracy of gene expression analysis. In order to validate our laser microdissection (LMD) method using the Leica AS LMD system (LEICA Microsystems), we compared the mRNA levels of three major genes involved in breast cancer (ERalpha, PR, HER2), measured by means of real-time quantitative RT-PCR, in 5000 microdissected malignant epithelial cells and in corresponding bulk tumor homogenates from 14 patients. We also compared the mRNA level results to protein expression measured by immunohistochemistry (IHC) on the same tumors. For the three genes, significant correlations were found between mRNA results obtained on microdissected cells and IHC. Comparison between IHC and mRNA results obtained on microdissected cells and bulk tumors showed that in all cases microdissection enhanced the sensitivity of assessing target gene transcript levels and was essential for their accurate evaluation in heterogeneous tumors.

Inter-laboratory quality control for hormone-dependent gene expression in human breast tumors using real-time reverse transcription-polymerase chain reaction

Quantitative reverse transcription-polymerase chain reaction (RT-PCR) used to detect minor changes in specific mRNA concentrations may be associated with poor reproducibility. Stringent quality control is therefore essential at each step of the protocol, including the PCR procedure. We performed inter-laboratory quality control of quantitative PCR between two independent laboratories, using in-house RT-PCR assays on a series of hormone-related target genes in a retrospective consecutive series of 79 breast tumors. Total RNA was reverse transcribed in a single center. Calibration curves were performed for five target genes (estrogen receptor (ER)alpha, ERbeta, progesterone receptor (PR), CYP19 (aromatase) and Ki 67) and for two reference genes (human acidic ribosomal phosphoprotein PO (RPLPO) and TATA box-binding protein (TBP)). Amplification efficiencies of the calibrator were determined for each run and used to calculate mRNA expression. Correlation coefficients were evaluated for each target and each reference gene. A good correlation was observed for all target and reference genes in both centers using their own protocols and kits (P < 0.0001). The correlation coefficients ranged from 0.90 to 0.98 for the various target genes in the two centers. A good correlation was observed between the level of expression of the ERalpha and the PR transcripts (P < 0.001). A weak inverse correlation was observed in both centers between ERalpha and ERbeta levels, but only when TBP was the reference gene. No other correlation was observed with other parameters. Real-time PCR assays allow convenient quantification of target mRNA transcripts and quantification of target-derived nucleic acids in clinical specimens. This study addresses the importance of inter-laboratory quality controls for the use of a panel of real-time PCR assays devoted to clinical samples and protocols and to ensure their appropriate accuracy. This can also facilitate exchanges and multicenter comparison of data.

[HER2 gene amplification assay: is CISH an alternative to FISH?]

The HER2 proto-oncogene encodes a transmembrane protein, which is considered to function as a growth factor receptor. Overexpression of this protein found by immunohistochemistry in about 20% of infiltrating breast carcinomas, has a predictive value of response to treatment by trastuzumab, an anti-HER2 humanized monoclonal antibody. Search for HER2 gene amplification is necessary to adapt the immunohistochemical technique quality and also in the cases of delicate analysis or weak overexpression. It is usually carried out by Fluorescence In Situ Hybridization (FISH). A more recent hybridization technique, named CISH because of its chromogenic revelation is an alternative method, which gives highly correlated results with FISH. We present details of this technique, which may be more familiar for the pathologists than FISH, because reading analysis is similar to that of immunohistochemical staining.

[Biopsy of breast microcalcifications using an 11-Gauge vacuum-assisted device: roles and challenges for the pathologist]

Stereotactic 11-Gauge vacuum-assisted biopsy provides a valuable tool in the diagnosis of mammographically detected breast microcalcifications. However, this new diagnostic technology presents some limitations and requires a close collaboration between radiologists, pathologists and physicians. The aim of this work is to propose a practical approach in the management of large core biopsies and to summarize the different difficulties faced by the pathologist in the management and histological interpretation of specimens issuing from this device.