Tumor heterogeneity and plasticity, driven by Epithelial-Mesenchymal Transition (EMT), enable cancer therapeutic resistance. We previously showed that EMT promotes primary cilia formation, which enables stemness and tumorigenesis in triple-negative breast cancer (TNBC). Here, we establish a role for primary cilia in human TNBC chemotherapeutic resistance. We developed patient-derived organoids, and showed that these recapitulated the cellular heterogeneity of TNBC biopsies. Notably, one of the identified cell states bore a quasi-mesenchymal phenotype, primary cilia, and stemness signatures. We treated our TNBC organoids with chemotherapeutics and observed partial killing. The surviving cells with organoid-reconstituting capacity showed selective enrichment for the quasi-mesenchymal ciliated cell subpopulation. Genomic analyses argue that this enrichment reflects a combination of pre-existing cells and ones that arose through drug-induced cellular plasticity. We developed a family of small-molecule inhibitors of ciliogenesis and show that these, or genetic ablation of primary cilia, suppress chemoresistance. We conclude that primary cilia help TNBC to evade chemotherapy. Significance Cancer cells that activate EMT to acquire a quasi-mesenchymal state form primary cilia to evade chemotherapy in human triple-negative breast cancer. Pharmacological inhibition of primary ciliogenesis counteracts EMT-induced chemoresistance. ### Competing Interest Statement The authors have declared no competing interest.

Purpose Triple-negative breast cancers (TNBC) account for 15% of all breast cancers but carry the worst prognosis. Because of their heterogenicity, these tumors are not all prone to targeted therapies. However, due to their high immune infiltration, targeting their immune microenvironment is of tremendous interest and is becoming the standard of care for high-risk early-stage TNBC. Nevertheless, the characterization of this immune infiltrate is often limited to general tumor-infiltrating lymphocytes (TILs) counting, without characterization of lymphocytes subtypes. Thus, we aimed at precisely characterizing these sub-populations and evaluating their prognostic significance.Methods We selected 91 TNBC tumors for which we had both the TILs count on hematoxylin and eosin (H&E) slides determined by an expert pathologist and the immune microenvironment cell subtypes characterization using flow cytometry (FC). We then compared the prognostic value of immune microenvironment subpopulations vs total TILs count.Results TNBCs contained a mean of 22.8±25.9% TILs in the tumor surface area, including mainly CD4+ helper T lymphocytes (14.1%), mostly Th2 (11.7%), CD8+ cytotoxic T lymphocytes (11.1%), and myeloid cells (8.4%) including antigen presenting cells (APC). The TILs count was correlated with the abundance of these cellular subpopulations (p≤0.004). TILs percentage was predictive of overall survival (OS) in univariate analysis (p=0.044), high APC infiltration was predictive of relapse-free survival (RFS) in univariate analysis (p≤0.030), and Th2 infiltration was predictive of both RFS and OS in univariate (p=0.009, 0.008 respectively) and multivariate analyses (p=0.002, 0.010 respectively).Conclusion The characterization of TILs composition is essential to better understand the potential antitumoral functions of these cells, and to strongly improve the associated prognostic and predictive values. We here demonstrate that Th2 subpopulation is associated with a better overall survival in TNBC and could be of use to predict response to the newly used immunotherapies.### Competing Interest StatementThe authors have declared no competing interest.### Funding StatementThis study was funded by grants from Rennes University Hospital (CORECT 2021-UF 8946-03) and association La Vannetaise### Author DeclarationsI confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.YesThe details of the IRB/oversight body that provided approval or exemption for the research described are given below:The Ethics Committee Review Board of Centre de lutte contre le Cancer Eugene Marquis gave ethical approval for this workI confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.YesI understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).YesI have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.YesAll data produced in the present study are available upon reasonable request to the authors* BC : Breast Cancer BCSC : Breast Cancer Stem Cell CD : Cluster of Differentiation DBCC : Differentiated Breast Cancer Cell DC : Dendritic cells DCIS : Ductal Carcinoma In Situ FC : Flow Cytometry FFPE : Formalin-Fixed Paraffin-Embedded H&E : Hematoxylin and Eosin LN : Lymph Node NAC : Neoadjuvant chemotherapy OS : Overall Survival pCR : pathological Complete Response pTNM : pathological classification of Tumor size (T), Node involvement (N), and Metastasis (M) according to international guidelines RFS : Relapse-Free Survival TC : T Cells (Lymphocytes) Th response : T helper response TILs : Tumor-Infiltrating Lymphocytes TNBC : Triple-Negative Breast Cancer

Purpose. Triple-negative breast cancers (TNBC) are defined as negative for hormonal receptors and human epidermal growth factor receptors 2 and account for 15% of breast cancers. TNBC carry the worst prognosis mainly because of their high proliferation index and the absence of efficient targeted therapies due to their molecular heterogeneity, even though some promising options are emerging. Besides, they do share a very high and distinct tumor-infiltrating lymphocytes (TILs) infiltration. Amongst TILs, CD8+ cytotoxic and CD4+ helper T-cells (TC) proved to be markers of a good outcome. However, pathologists routinely quantify overall TILs density only. Anti-PD-1/PD-L1 immunotherapies recently became available for immunosuppressive TNBC. Unfortunately, neither PD-1/PD-L1 expression nor TILs quantification is able to predict patients’ responses accurately. Thus, we aimed at precisely characterizing TILs sub-populations and evaluating their prognostic significance before their predictive one. Methods. We selected 91 patients at the time of surgery before any adjuvant therapy from January 2013 to December 2018 in Rennes, France. TNBC tumors went through TILs quantification on hematoxylin and eosin slides by a trained pathologist and immune microenvironment characterization using flow cytometry. We then compared the prognostic value of immune microenvironment subpopulations vs total TILs count. Results. TNBCs contained a mean of 22.8±25.9% TILs, including CD4+ TC (14.1%) mainly made of Th2 (11.7%), CD8+ TC (11.1%), and myeloid cells (8.4%) such as antigen presenting cells (APC). TILs groups and percentages were correlated with the abundance of these cellular subpopulations (p≤0.004). TILs percentage was predictive of overall survival (OS), while high APC infiltration was of relapse-free survival (RFS) in univariate analyses (p=0.044 & p≤0.030 respectively). Only Th2 infiltration was predictive of both RFS and OS in univariate (p=0.009 & p=0.008 respectively) and multivariate analyses (p=0.002 & p=0.010 respectively). When considering the different Th populations, only Th2 was a better predictive factor of survival than total leukocytes. Discussion. The development of immune therapies aiming at unlocking the anti-tumor immune response has revealed the desperate need to better characterize the tumor immune infiltrate. TILs quantification by pathologists is the only parameter routinely measured so far but it must be standardized since variability can affect their correlation with pCR. In our study, and contrary to most previous ones, stromal TILs were not significantly associated with RFS and OS. Thus, the characterization of TILs subtypes is critical since they can have either a pro- or an anti-tumorigenic function. Thus, we counteracted the limitations of TILs pathological quantification by finely characterizing the immune infiltrate using flow cytometry. Th2 infiltrate was the most frequent, as previously reported, and counterintuitively, was associated with a favorable prognostic value. This is rarely shown as Th2 infiltration is frequently reported to favor pro-tumorigenic immune tolerance. This proves that a more refined characterization of the intra-tumoral immune landscape is essential to derive interesting therapeutic perspectives, either by recapacitating Th2 response or by targeting their interaction with other immune subsets, like fibroblasts, macrophages, dendritic cells, or eosinophils and IgE. Finally, immunotherapies modulating Th2 response could also be used around the time of surgery that has been proved to induce immunomodulation. Conclusion. The characterization of TILs composition is essential to better understand the potential antitumoral functions of these cells and to substantially improve the associated prognostic and predictive values. Citation Format: Susie Brousse, Florence Godey, Elodie Laffont, Patrick Tas, Boris Campillo-Gimenez, Vincent Lavoué, Matthieu Le Gallo. Evaluation of T-cell infiltrating lymphocytes vs. Th2 in triple negative breast cancers (TNBC) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P2-11-23.

Introduction Follicular helper T-cell lymphomas (TFHL) have an aggressive course with a poor outcome. European and US guidelines recommend anthracycline-based chemotherapy as a first-line treatment, but the 5-year overall survival rate is still approximately 30%. We describe here the features of a cohort of TFHL patients who experienced prolonged survival despite the absence of specific treatment or the initiation of steroid-based therapy. Patients and methods In our study, we describe 15 adult patients who suffered from TFHL and had not received intensive chemotherapy at diagnosis for any reason. Biopsies of these cases were centrally reviewed, and the mutational pattern was determined using next-generation sequencing. Results These 15 patients had the classic clinical, biological and pathological features of TFHL, angioimmunoblastic-type. TET2 mutations were found in 83% of patients; RHOA G17V, IDH2 R172 and DNMT3A mutations were found in 67%, 42% and 33% of the patients, respectively. Among the 15 patients, 8 did not receive any treatment, and 7 received steroid-based treatment. Ten patients had progression (5 in each group). Four patients died (3 of them from the progression of their lymphoma). The median follow-up in our cohort was 53 months. The 5-year OS was 66%, 100% for untreated patients and 29% for the others. In those 2 groups, the median time to treatment initiation was 22 months from diagnosis. Conclusion We described a series of 15 well-characterized TFHL patients with an indolent outcome, suggesting that a watch-and-wait approach can be proposed in selected patients. Identifying factors predicting such evolution is warranted.

Expression of hormone receptor (HR) for estrogens (ER) and progesterone (PR) and HER2 remains the cornerstone to define the therapeutic strategy for breast cancer patients. We aimed to compare phenotypic profiles between matched primary and metastatic breast cancer (MBC) in the ESME database, a National real-life multicenter cohort of MBC patients. Patients with results available on both primary tumour and metastatic disease within 6 months of MBC diagnosis and before any tumour progression were eligible for the main analysis. Among the 16,703 patients included in the database, 1677 (10.0%) had available biopsy results at MBC diagnosis and on matched primary tumour. The change rate of either HR or HER2 was 27.0%. Global HR status changed (from positive = either ER or PR positive, to negative = both negative; and reverse) in 14.2% of the cases (expression loss in 72.5% and gain in 27.5%). HER2 status changed in 7.8% (amplification loss in 45.2%). The discordance rate appeared similar across different biopsy sites. Metastasis to bone, HER2+ and RH+/HER2- subtypes and previous adjuvant endocrine therapy, but not relapse interval were associated with an HR discordance in multivariable analysis. Loss of HR status was significantly associated with a risk of death (HR adjusted = 1.51, p = 0.002) while gain of HR and HER2 discordance was not. In conclusion, discordance of HR and HER2 expression between primary and metastatic breast cancer cannot be neglected. In addition, HR loss is associated with worse survival. Sampling metastatic sites is essential for treatment adjustment.

The Epithelial–Mesenchymal Transition (EMT) and primary ciliogenesis induce stem cell properties in basal Mammary Stem Cells (MaSCs) to promote mammogenesis, but the underlying mechanisms remain incompletely understood. Here, we show that EMT transcription factors promote ciliogenesis at intermediate EMT transition states by activating ciliogenesis inducers, including FGFR1. The resulting primary cilia promote BBS11-dependent ubiquitination and inactivation of a central signaling node, GLIS2. We show that GLIS2 inactivation promotes MaSC stemness, and GLIS2 is required for normal mammary gland development. Moreover, GLIS2 inactivation is required to induce the proliferative and tumorigenic capacities of the Mammary-Tumor-initiating cells (MaTICs) of claudin-low breast cancers. Claudin-low breast tumors can be segregated from other breast tumor subtypes based on a GLIS2-dependent gene expression signature. Collectively, our findings establish molecular mechanisms by which EMT programs induce ciliogenesis to control MaSC and MaTIC biology, mammary gland development, and claudin-low breast cancer formation.

ObjectivePeritoneal or mesenteric tumours may correspond to several tumour types or tumour-like conditions, some of them being represented by histiocytosis. This rare condition often poses diagnostic difficulties that can lead to important time delay in targeted therapies. Our aim was to describe main features of histiocytoses with mesenteric localisation that can improve the diagnostic process.DesignWe performed a retrospective study on 22 patients, whose peritoneal/mesenteric biopsies were infiltrated by histiocytes.ResultsAbdominal pain was the revealing symptom in 10 cases, and 19 patients underwent surgical biopsies. The diagnosis of histiocytosis was proposed by initial pathologists in 41% of patients. The other initial diagnoses were inflammation (n=7), sclerosing mesenteritis (n=4) and liposarcoma (n=1). The CD163/CD68+CD1a- histiocytes infiltrated subserosa and/or deeper adipose tissues in 16 and 14 cases, respectively. ABRAFV600Emutation was detected within the biopsies in 11 cases, and two others were MAP2K1 mutated. The final diagnosis was histiocytosis in 18 patients, 15 of whom had Erdheim-Chester disease. The median diagnostic delay of histiocytosis was 9 months. Patients treated with BRAF or MEK inhibitors showed a partial response or a stable disease. One patient died soon after surgery, and five died by the progression of the disease.ConclusionDiagnosis of masses arising in the mesentery should be carefully explored as one of the possibilities in histiocytosis. This diagnosis is frequently missed on mesenteric biopsies. Molecular biology for detecting the mutations in BRAF or in genes of the MAP kinase pathway is a critical diagnostic tool.

Composite and sequential lymphomas involving both classical Hodgkin lymphoma (CHL) and primary mediastinal B-cell lymphoma (PMBCL) are rare phenomena. Beyond the relevant biological interest raised by these cases, treatments and outcome data are poorly covered in the recent literature. This retrospective analysis describes the pathological and clinical characteristics of 10 composite and 15 sequential cases included after a central pathological review. At diagnosis, 70% of the composite lymphomas presented a disseminated and extranodal disease. Among the 15 sequential lymphomas, 12 were CHL at first occurrence and three were PMBCL. Based on their clinical evolution, these sequential lymphomas could be divided into early (i.e., diagnosis of second lymphoma within a year) and late [(i.e., a second lymphoma occurrence occurring after a long period of complete remission]). All composite cases were alive in complete remission after a median follow-up of 34 months. If the early sequential lymphoma presented a particularly poor outcome with a median overall survival shorter than one year, the late cases were efficiently salvaged. Further molecular studies are needed to describe the underlying biology of these rare diseases, possibly representing the extreme of tumour cell plasticity found in grey-zone lymphoma.

Abstract Background: Therapeutic options at diagnosis for metastatic breast cancers (MBC) differ largely according to cancer phenotype (namely, hormone receptor (HR) and HER2 status). Reported discordance rates between primary tumor and metastasis vary widely in literature, with a median of 18% for estrogen receptor, 31% for progesterone receptor and 10% for HER2. The present study aimed to compare phenotypic profiles between primary and MBC in the real-life setting. Patients (pts) and methods: Epidemio-Strategy and Medical Economics (ESME)MBC data platform (NCT03275311) is a French national, multicenter, observational cohort using clinical trials' methodology for data capture, monitoring and quality controls. At the time of analysis, it comprised data of 16703 consecutive newly diagnosed MBC pts (1/01/08-31/12/14) treated in 18 French comprehensive cancer centres. The primary endpoint was the discordance rate of HR and HER2 status between primary tumor and MBC (biopsy of metastatic site done within 6 months of MBC diagnosis). Only patients with both histological reports available were considered. Potential factors associated with phenotype discordance were assessed in a multivariate logistic regression. Results: 2933 out of 16703 (17.6%) had a biopsy in the first 6 months of metastatic disease. HR and/or HER2 status was available in 1677 pts. The discordance rate between primary and matched MBC was 14.2% (222/1566) for HR: loss of expression in 72.5%, gain in 27.5%. For HER2, the discordance rate was 7.8% (84/1076): 45.2% of losses and 54.8% of gains of expression. The primary HR+/HER2+ subgroup had the highest rate of changes: 53% (49/92) with either a loss of HR (43%), loss of HER2 (43%) or a loss of both (14%). 18% (33/181) of primary triple-negative breast cancer (TNBC) had a phenotypic change with a majority of HR gain (79%). In multivariate analysis, administration of adjuvant chemotherapy +/- targeted therapy was the sole independent predictor of HR status modification (OR: 1.73, 95%CI 1.27-2.36, p=0.001). The presence of a mixed histology was the only predictor of HER2 discordance (OR =2.57, 95%CI 1.19-5.55, p=0.016). Patient characteristics Total population (n=16703)Pts with primary and MBC phenotype available (n=1677)Age at metastatic diagnosis Median (range)61 (19-99)60 (24-93)De novo MBC4507 (27.1%)221 (13.2%)Number of metastatic sites Median (range)1 (1-9)2 (1-7)MBC sites Brain1200 (7.2%)138 (8.2%)Visceral7755 (46.4%)928 (55.3%)Non-visceral7748 (46.4%)611 (36.4%)Phenotypic profileN = 2933N=1677TNBC356 (18.5%)272 (19.3%)HR+/HER2-1251 (65.0%)917 (65.2%)HR-/HER2+150 (7.8%)105 (7.5%)HR+/HER2+168 (8.7%)112 (8%)Missing1008271Metastatic site samplingN=2933N=1677Bone692 (24.2%)419 (25.5%)Liver514 (18.0%)355 (21.6%)Skin379 (13.3%)203 (12.4%)Node306 (10.7%)169 (10.3%)Lung258 (9.0%)168 (10.2%)Pleura283 (9.9%)121 (7.4%)CNS/CSF*132 (4.6%)42 (2.6%)Other or multiple296 (10.3%)165 (10.0%)Missing7335* CNS= central nervous system, CSF=cerebro-spinal fluid Conclusion: Biopsy and phenotype re-evaluation of MBC early in the disease course has a confirmed potential significant therapeutic impact in this large scale real life setting and should be proposed as often as possible. Citation Format: Lefevre S, Lusque A, Joyon N, Arnould L, Penault-Llorca F, MacGrogan G, Treilleux I, Vincent-Salomon A, Haudebourg J, Maran-Gonzalez A, Charafe-Jauffret E, Courtinard C, Franchet C, Verriele V, Brain E, Tas P, Delaloge S, Filleron T, LaCroix-Triki M. Phenotypic discordance between primary and metastatic breast cancer (MBC) in a large scale real-life multicentre French cohort [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-12-05.

Background The EndoPredict (EP) test has been developed and validated for assessing recurrence risk in patients with estrogen receptor (ER)-positive HER2-negative breast cancer (BC). This test is based on the expression of 12 genes (molecular score), combined with clinicopathological criteria (i.e. tumor size and nodal status) (EPclin risk score). For node-positive patients, the weight given to the node status in the EPclin score is similar when considering pN1mi (]0.2-2mm]) or pN1 (>2mm, 1-3 positive lymph nodes). Our aim was to characterize the EPclin classification of the pN1mi subgroup in the French national registry for molecular signatures in ER+ BC. Methods Since April 2016, nine French laboratories using EP test in clinical practice prospectively implement a national registry for molecular prognostic signatures in ER+ BC. We analyzed the pN1mi subgroup with regards to their clinico-pathological characteristics, molecular EP score and EPclin risk score. Using the definition formula of the EPclin score [EPclin=0.35t + 0.64n + 0.28EP, with n=1 for pN0, 2 for pN1mi/pN1, 3 for pN2, 4 for pN3], we could calculate a hypothetical EPclin score if the pN1mi had been considered as pN0 [n factor=1]. Results By the end of 2017, the database included 1246 EP tests performed in routine practice, including 67 (5.4%) pN1mi. The pN1mi BC were ER+ HER2- (67/67, 100%), invasive carcinoma of no special type in 52/67 (78%), with a median tumor size of 18 mm (range 7-45; pT1c in 40/67). Among these, 22 were classified as EPclin low and 45 as EPclin high, with a median EP score of 6 (range 2-14), a median EPclin score of 3.70 (range 3-6), and a median relapse risk at 10-year of 15%(range 5-73). Most interestingly, 23/67 (34%; i.e. 1.8% of all EP tests performed) pN1mi BC displayed an EPclin score comprised between 3.4 and 4, just above the cut-off value of 3.3: these cases (and only these cases) would have been classified in a different risk category (i.e. EPclin low risk) if the node status would have been considered as negative. Conclusion With regards to EndoPredict test in pN1mi BC - and the persistent debate as to whether they should bear the same weight as node-positive (pN1) or negative (pN0) tumors - categorization in the EPclin class is not likely to be impacted by the node factor weight in the vast majority (>65%) of the pN1mi cases and >98% of all patients tested with EP. Only cases with an EPclin between 3.4 and 4 might be impacted. Citation Format: LaCroix-Triki M, Arnould L, MacGrogan G, Penault-Llorca F, Haudebourg J, Tas P, Garnier A, Vincent-Salomon A, Miquel C, Lehmann-Che J, Callens C, Quillien V, Cayre A, Lamy P-J, Rouleau E, De Cremoux P. EndoPredict prognostic signature in pN1mi, estrogen receptor-positive breast cancer: analysis of the French national registry for molecular signatures [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-08-23.

L’OMS individualise de nombreux sous-types de lymphomes non-hodgkiniens selon leurs caractéristiques histologiques, génétiques et immunophénotypiques. La distinction entre un lymphome B diffus à grandes cellules (LBDGC) et un lymphome à cellules du manteau (LCM) pléomorphe peut être difficile. Nous présentons ici un cas exceptionnel de lymphome B agressif présentant un triple réarrangement des gènes Bcl-6, c-Myc et CCND1. La patiente âgée de 62 ans a présenté un tableau de tuméfaction inguinale unilatérale de taille rapidement croissante, d’origine ganglionnaire probable, associée à un tableau neurologique atypique. La ponction lombaire retrouvait un contingent de cellules anormales, compatible avec un envahissement neuro-méningé de maladie lymphomateuse. Ni l’examen clinique, ni l’imagerie TEP n’ont identifié d’autres atteintes. Une biopsie de cette masse a été réalisée. L’analyse anatomopathologique a mis en évidence une prolifération lymphomateuse diffuse de cellules de taille moyenne exprimant CD20, BCL-6, MUM-1, C-MYC et BCL-1. L’indice de prolifération Ki-67 était > 95 %. Une étude par hybridation in situ en fluorescence a retrouvé un réarrangement des gènes Bcl-6, c-Myc et CCND1 au sein des mêmes cellules. De rares lymphomes composites associant un LBDGC et un LCM ont été décrits [1] ainsi que 3 cas de LBDGC avec un double réarrangement des gènes Bcl-6 et CCND1 [2]. L’observation, ici, d’un réarrangement du gène CCND1 ainsi que d’un profil immunohistochimique et cytogénétique commun à l’ensemble des cellules tumorales a orienté le diagnostic vers un LCM pléomorphe. Il s’agit, à notre connaissance, du premier cas rapporté présentant un réarrangement de CCND1, Bcl-6 et c-Myc. Nous formulons l’hypothèse que ce triple réarrangement favorise une plus grande agressivité tumorale. La recherche systématique des réarrangements des gènes Bcl-2, Bcl-6, c-Myc et CCND1, dans les lymphomes B diffus exprimant BCL-1, pourrait permettre de préciser la fréquence de cette entité et le pronostic individuel des patients.

Introduction: : This study sought to identify predictive factors of involved surgical margins in breast-conserving surgery (BCS) after neoadjuvant chemotherapy (NAC) to help guide the surgical procedure. Materials and Methods: : Retrospective study of patients who had BCS after NAC between January 2008 and December 2013. Outcome measure: tumor-involved margin, defined by tumor cells on ink for invasive cancer and tumor-free margin < 2 mm for DCIS. Results: : Ninety-seven patients were included. The median age of patients was 46 years old [28-71]. The initial average tumor size was 47.8 mm [+/- 18.6]. Twelve patients (12.4%) had involved tumor margins on final histology after BCS and NAC. According to the multivariate model including only preoperative variables of positive margins, initial ultrasound tumor size <= 27 mm (p = 0.045) and low SBR grade (p = 0.009) were independently associated with tumor-involved margins. According to the multivariate model including pre- and postoperative variables of positive margins, ductal carcinomain situ was also independently associated with tumor-involved margins (p = 0.021). Conclusion: : Initial ultrasound tumor size <= 27 mm and low SBR grade were independently associated with tumor-involved margins. These preoperative data were very helpful to guide the surgical procedure in breast cancer. (C) 2019 Elsevier Masson SAS. All rights reserved.

The use of novel methods to characterize living tumor cells relies on well-conceived biobanks. Herein, we raised the question of whether the composition of fresh and freeze/thawed dissociated tumor samples is comparable in terms of quantitative and qualitative profiling.

Purpose To prospectively assess the clinical impact of expert review of lymphoma diagnosis in France. Materials and Methods From January 2010 to December 2013, 42,145 samples from patients with newly diagnosed or suspected lymphomas were reviewed, according to the 2008 WHO classification, in real time by experts through the Lymphopath Network. Changes in diagnosis between referral and expert review were classified as major or minor according to their potential impact on patient care. Results The 42,145 reviewed samples comprised 36,920 newly diagnosed mature lymphomas, 321 precursor lymphoid neoplasms, 314 myeloid disorders, and 200 nonhematopoietic neoplasms, with 4,390 benign lesions. There were 4,352 cutaneous and 32,568 noncutaneous lymphomas. The most common mature noncutaneous lymphomas were diffuse large B-cell lymphomas (32.4%), follicular lymphomas (15.3%), classic Hodgkin lymphomas (13%), peripheral T-cell lymphomas (6.3%) of which angioimmunoblastic T-cell lymphomas (2.3%) were the most frequent, and mucosa-associated lymphoid tissue lymphomas (5.8%). A diagnostic change between referral and expert review occurred in 19.7% of patients, with an estimated impact on patient care for 17.4% of patients. This rate was significantly higher for patients sent with a provisional diagnosis seeking expert second opinion (37.8%) than for patients sent with a formal diagnosis (3.7%). The most frequent discrepancies were misclassifications in lymphoma subtype (41.3%), with 12.3% being misclassifications among small B-cell lymphoma entities. Fewer than 2% of changes were between benign and malignant lymphoid conditions. Minor changes (2.3%) mostly consisted of follicular lymphoma misgrading and diffuse large B-cell lymphoma subtype misclassification. Conclusion To our knowledge, this study provides the largest ever description of the distribution of lymphoma entities in a western country and highlights how expert review significantly contributes to a precise lymphoma diagnosis and optimal clinical management in a proportion of patients.

Les systèmes de capture et d'analyse d'image permettent une analyse par FISH semi-automatisée des coupes de tissus fixés par le formol et inclus en paraffine. Le service de cytogénétique et biologie cellulaire du CHU de Rennes est équipé du système BIOVIEW® - Encore, pouvant scanner 200 lames par série avec une caméra haute résolution. Nous rapportons l'étude de 47 cas de lymphomes. L'analyse histologique correspondait à 42 lymphomes B diffus à grandes cellules pour lesquels un réarrangement des gènes BCL2, BCL6 et MYC a été recherché ainsi que 5 lymphomes folliculaires analysés pour les gènes BCL2 et BCL6 avec les sondes VYSIS® LSI BA correspondantes. Une analyse semi-automatique a été possible pour 73 % (99/136) des lames avec des résultats sans ambiguïté (réarrangement de BCL2 [n = 9], BCL6 [n = 8], MYC [n = 8], non réarrangés [n = 63]) dans 89 % (88/99) et douteux dans 11 % (11/99). Pour ces derniers, l'analyse manuelle au microscope a permis à chaque fois de confirmer le résultat initialement suspecté (réarrangement de BCL2 [n = 1], BCL6 [n = 2], MYC [n = 3], non réarrangés [n = 5]). Les résultats étaient non contributifs pour 27 % (37/136) des préparations. Une lecture manuelle au microscope a permis un rendu de résultat dans 35 % (13/37) des cas alors que les autres (24/37) restaient non interprétables. Le temps nécessaire pour l'analyse semi-automatisée d'une préparation (12 ± 7 min) était inférieur à celui de l'analyse manuelle (23 ± 5 min). Ces résultats montrent l'intérêt de l'utilisation en routine du système BIOVIEW® - Encore pour l'analyse par FISH des lymphomes. Outre le gain de temps et l'analyse ciblée des zones d'intérêt, ce système permet l'archivage automatique et standardisé des images. Son utilisation systématique est en cours pour les autres activités du service (tumeurs solides, onco-hématologie, cytogénétique constitutionnelle/prénatale) ainsi qu'en recherche pour l'étude de l'hétérogénéité tumorale.

Le cours en ligne ouvert et massif (Massive open online course [MOOC]) « Stratégies diagnostiques des cancers » a été dispensé à l’automne 2016 sur la plateforme France université numérique à deux niveaux d’apprenants : les étudiants de premier cycle dans le domaine de la santé et de la biologie, et le grand public. Parmi les 5285 inscrits dans 81 pays différents, 1237 apprenants (23 %) ont obtenu une attestation de suivi avec succès. Ce MOOC a par ailleurs été intégré à des unités d’enseignement pour des étudiants en médecine de DFGSM3 des universités Paris Diderot et Paris 13. À l’aide de questionnaires anonymes auprès des participants avant et après le MOOC, il a été montré que l’anatomie et cytologie pathologiques est moins bien connue que les autres spécialités médicales. La participation au MOOC a permis une nette amélioration des connaissances des participants concernant la place et le rôle du médecin pathologiste dans le diagnostic des cancers. Concernant les étudiants ayant suivi le MOOC dans le cadre de leur cursus universitaire, les retours sont très positifs, mais il est nécessaire d’apporter des aménagements substantiels des volumes et contenus des enseignements présentiels complémentaires.The Massive Open Online Course (or MOOC) “Diagnostic Strategies Cancers”, was hosted in autumn 2016 on the platform “France Université Numérique” and had two levels of learners: students in the field of health and biology and the general public. Of the 5285 learners in 81 different countries, 1237 (23%) were successfully certified. This MOOC was also integrated into the teaching program of medical students of Paris Diderot University and Paris 13 University. Using anonymous questionnaires before and after MOOC, it has been shown that pathology is less known than other medical specialties. Participation in this MOOC led to a marked improvement in participants’ knowledge of the place and role of the pathologist in the diagnosis of cancers. Regarding the students who have followed the MOOC as part of their university course, their comments were very positive, but it is necessary to make substantial adjustments in the amounts and contents of the campus-based courses.