Assessment of the reliability of MSI status and dMMR proteins deficiency screening on endoscopic biopsy material in esophagus and gastric adenocarcinoma.

BACKGROUND: Microsatellite instability (MSI) is a negative predictive factor for neoadjuvant chemotherapy in resectable oesogastric adenocarcinoma and a crucial determinant for immunotherapy. We aimed to evaluate reliability of dMMR/MSI status screening performed on preoperative endoscopic biopsies. METHODS: Paired pathological samples from biopsies and surgical specimen of oesogastric adenocarcinoma were retrospectively collected between 2009 and 2019. We compared dMMR status obtained by immunohistochemistry (IHC) and MSI status by PCR. dMMR/MSI status on surgical specimen was considered as reference. RESULTS: PCR and IHC were conclusive on biopsies respectively for 53 (96.4%) and 47 (85.5%) of the 55 patients enrolled. IHC was not contributive for 1 surgical specimen. A third reading of IHC was carried out for 3 biopsies. MSI status was observed in 7 (12.5%) surgical specimens. When analyses were contributive, sensitivity and specificity of biopsies for dMMR/MSI were respectively 85% and 98% for PCR vs. 86% and 98% for IHC. Concordance rate between biopsies and surgical specimen was 96.2% for PCR and 97.8% for IHC. CONCLUSIONS: Endoscopic biopsies are a suitable source of tissue for dMMR/MSI status determination in oesogastric adenocarcinoma which should be routinely performed at diagnosis to better adapt neoadjuvant treatment. MINIABSTRACT: By comparison of dMMR phenotype obtained by immunohistochemistry and MSI status by PCR between match-paired samples of oesogastric cancer's endoscopic biopsies and surgical specimen, we observed that biopsies are a suitable source of tissue for dMMR/MSI status determination.

Une lésion labiale inhabituelle.

A 75 years old patient presented with a papular easily bleeding lesion of the lower lip that had been growing for two months. He was known for alcoholic cirrhosis complicated with hepatocellular carcinoma treated since one year. A working diagnostic hypothesis of benign vascular lesion was proposed. Microscopic examination showed a neoplastic dermal proliferation that had been fully excised, made of lobules segregated by thin fibrous septae. The neoplastic architecture was trabecular and delineating spaces forming pseudo-rosettes. Tumour cells were monomorphic, cuboidal or cylindric with abundant eosinophilic and granulous cytoplasm and centered by a lone nucleus that often contained a prominent nucleolus. Some spaces were filled with a brownish-greenish pigmented material. Immunohistochemical study showed that tumour cells were positive with the hepatocyte paraffin 1 antibody as well as cytokeratin 8 antibody. Chromogranin A and synaptophysin stainings were negative. Thus we concluded to a lip metastasis from the previously known hepatocellular carcinoma. Skin metastasis arise in around 3% of cases of hepatocellular carcinoma. They account for less than 1% of all cutaneous metastasis. Overall appearance of cutaneous metastasis of hepatocellular carcinoma is associated with a poor prognosis and an aggravated risk of metastasis to other locations and organs and a median overall survival of less than 5 months. Since incidence of hepatocellular carcinoma is rising pathologists might face more frequently in years to come to cutaneous metastasis whose varied clinical presentations make a diagnostic challenge.

A massive open online course to teach undergraduate medical students in oncology: keys of success.

Massive Open Online Courses (MOOCs) are gaining popularity in education while classroom lectures are being deserted, especially after COVID-19 pandemic. Their added value in teaching undergraduate medical students remains to be confirmed. This study evaluated a MOOC devoted to undergraduate medical students in a blended oncology-teaching university program. It was the first to target undergraduate medical students in oncology at its beginning. Students were asked to participate in a survey before and after MOOC to explore interactions between their characteristics and final grades, 65% of the participating students belonged to the rich class. 70% of the students completed the MOOC. Grades distributions were similar before and after MOOC implementation, so MOOC doesn't alter overall results. In addition, there was a positive effect of the MOOC on median grades on the immediate test. The univariate and multivariate analysis showed that socioeconomic status and student's willingness to participate interacted significantly with final results. Particularly, students' motivation and satisfaction were associated with better results; Almost 70% of students asked for blended learning. E-learning is reliable to teach oncology to undergraduate medical students. The success is directly linked to students' willingness to participate, and can be improved using blended methods including tutorials.

[The first data challenge of the french society of pathology: An international competition in 2020, a research tool in A.I. for the future?] / Le premier data challenge organisé par la Société Française de Pathologie : une compétition internationale en 2020, un outil de recherche en intelligence artificielle pour l'avenir ?

The french society of pathology (SFP) organized in 2020 its first data challenge with the help of Health Data Hub (HDH). The organisation of this event first consisted in recruiting almost 5000 slides of uterus cervical biopsies obtained in 20 pathology centers. After having made sure that patients did not refuse to include their slides in the project, the slides were anonymised, digitized and annotated by expert pathologists, and were finally uploaded on a data challenge platform for competitors all around the world. Competitors teams had to develop algorithms that could distinguish among four diagnostic classes in epithelial lesions of uterine cervix. Among many submissions by competitors, the best algorithms obtained an overall score close to 95%. The best 3 teams shared 25k€ prizes during a special session organised during the national congress of the SFP. The final part of the competition lasted only 6 weeks and the goal of SFP and HDH is now to allow for the collection to be published in open access. This final step will allow data scientists and pathologists to further develop artificial intelligence algorithms in this medical area.

Haemorrhagic shock secondary to a diffuse ulcerative enteritis after Ipilimumab and Nivolumab treatment for metastatic melanoma: a case report.

We provide a unique case of haemorrhagic shock complicating a corticosteroid-resistant diffuse ulcerative enteritis in a patient treated with a combination of an anti cytotoxic T-lymphocyte antigen-4 (CTLA4) and an anti programmed cell death protein 1 (PD-1) for metastatic melanoma. Immunotherapy has changed the perspective for the management of patients with metastatic melanoma but are also responsible for digestive complications mainly represented by immunomediated colitis. Digestive bleeding is common in patients with extensive colonic lesions but has never been described in enteritis independent of colitis. The patient with acute intestinal obstruction related ileitis without evidence of stricture on imaging and then had a gastro-intestinal bleed. In the absence of haemorrhagic lesions on upper gastrointestinal endoscopy, colonoscopy and computed tomography (CT) angiography, a surgical exploration with enteroscopy was performed. This revealed an extensive ulcerated jejunoileitis, with active bleeding, within a Meckel's diverticulum. Management included resection of the Meckel diverticulum with a transient double barrel ileostomy. Two infliximab infusions were given due to persistent bleeding. We observed a dramatic improvement after infliximab treatment with complete cessation of bleeding and no further need for transfusions. A complete mucosal healing has been achieved on enteroscopy at 3 months with disappearance of histological inflammatory lesions. This observation suggests that infliximab represents a therapeutic option in severe enteritis and may be as effective as in more moderate immune-mediated enterocolitis.

Can AI predict epithelial lesion categories via automated analysis of cervical biopsies: The TissueNet challenge?

The French Society of Pathology (SFP) organized its first data challenge in 2020 with the help of the Health Data Hub (HDH). The organization of this event first consisted of recruiting nearly 5000 cervical biopsy slides obtained from 20 pathology centers. After ensuring that patients did not refuse to include their slides in the project, the slides were anonymized, digitized, and annotated by expert pathologists, and finally uploaded to a data challenge platform for competitors from around the world. Competing teams had to develop algorithms that could distinguish 4 diagnostic classes in cervical epithelial lesions. Among the many submissions from competitors, the best algorithms achieved an overall score close to 95%. The final part of the competition lasted only 6 weeks, and the goal of SFP and HDH is now to allow for the collection to be published in open access for the scientific community. In this report, we have performed a "post-competition analysis" of the results. We first described the algorithmic pipelines of 3 top competitors. We then analyzed several difficult cases that even the top competitors could not predict correctly. A medical committee of several expert pathologists looked for possible explanations for these erroneous results by reviewing the images, and we present their findings here targeted for a large audience of pathologists and data scientists in the field of digital pathology.

Prevalence and prognosis of microsatellite instability in oesogastric adenocarcinoma, NORDICAP 16-01.

BACKGROUND: The prevalence and prognosis association of microsatellite instability (MSI) in oesogastric junction and gastric adenocarcinoma (OGC) have been reported with conflicting results. METHODS: Patients with OGC from 2010 to 2015 were enrolled in this retrospective multicenter study. MSI was determined by genotyping. MLH1 promoter methylation and BRAFV600E mutation were screened in the MSI tumors. RESULTS: Among 315 tumors analyzed, 39 (12.4%) were of the MSI phenotype. Compared to MSS tumors, MSI tumors were more frequent in patients >70 years (17% vs 9%, p=0.048) and in gastric antral primary (20% versus 5% in junction tumor and 12% in fundus tumor. Among 29 MSI tumors analyzed, 28 had a loss of MLH1 protein expression and 27 had MLH1 promotor hypermethylation. None had a BRAF V600E mutation. The 4-year cumulative incidence of recurrence for patients with resected tumor was significantly lower in dMMR tumors versus pMMR tumors (17% versus 47%, p=0.01). For the patients with unresectable tumor the median overall survival was 11 months in MSS group and 14 months in MSI group (p=0.24). CONCLUSION: MSI prevalence in OGC was 12.4%, associated with antral localization and advanced age. Patients with MSI tumors had a lower cumulative incidence of recurrence after surgery. MSI phenotype was mainly associated with loss of MLH1 protein expression, MLH1 promotor hypermethylation and had no BRAFV600E mutation.

[An unusual digestive complication under anti-PD-1 (pembrolizumab)]. / Une complication digestive rare sous anti-PD-1 (pembrolizumab).

The most commonly reported pattern of anti-PD-1 induced colitis is an active colitis characterized by neutrophilic inflammation and prominent apoptosis. On the other hand, reports of collagenous colitis (which is a microscopic colitis) are exceptional. In this report, we describe an unusual case of anti-PD1-associated collagenous colitis in a 76-year-old man, treated with pembrolizumab for a stage IV cutaneous melanoma. Fourteen months after the start of pembrolizumab, the patient developed a grade 3 diarrhea (up to 9 stools per day) associated with profound hypokalemia. No bacterial, viral or parasitological infectious agents were found from stool analysis. The rectosigmoidoscopy showed colonic diffuse congestion with no ulceration. Systematic biopsies were performed during endoscopy. Histologically, the fragments analyzed revealed a moderately thickened subepithelial collagen layer (20-30µm thick) associated with a mild mixed inflammatory infiltrate within the lamina propria. There were no granuloma lesions, ulcerations or viral inclusion bodies. The patient was initially successfully treated with corticosteroids (prednisone) and temporary interruption of pembrolizumab. However, during corticosteroids tapering, a relapse was observed. The treatment was switched to budesonide, leading to a complete and definitive resolution of diarrhea. To date, budesonide has been stopped and pembrolizumab has not been restarted. Currently, there is a bone progression treated by radiotherapy alone. In case of a more important progression, a systemic treatment will be secondarily discussed.

[Large bowel ganglioneuromatosis associated with neurofibromatosis type 1]. / Ganglioneuromatose du tube digestif dans le cadre d'une neurofibromatose de type 1.

Gastrointestinal tract ganglioneuromatosis is a rare condition, which is isolated or included in a syndromique disease. Multiple endocrine neoplasia type 2 is the most frequently associated syndrome. Association with type 1 neurofibromatosis has also been established, but much rarely. We report the case of large bowel ganglioneuromatosis found incidentally in a patient with type 1 neurofibromatosis.

Severe gastrointestinal toxicity of MEK inhibitors.

Gastrointestinal toxicities of MEK inhibitors in melanoma patients are frequent. In clinical trials, the most common digestive adverse events were nausea, vomiting, and diarrhoea. However, severe toxicities such as colitis and gastrointestinal perforation, some with fatal outcomes, have been reported. These rare but severe adverse events are not well described. We performed a retrospective analysis of all patients with stage IV and unresectable stage III melanoma treated with a MEK inhibitors at Saint-Louis Hospital, Paris, between 1 August 2013 and 15 October 2018. Among 119 patients exposed to MEK inhibitors, 78 were treated with trametinib, 19 with cobimetinib, four with binimetinib, and 18 patients with two different MEK inhibitors at separate times. All grade digestive adverse events were observed in 39 (32.7%) patients. Grade 3 and 4 adverse events occurred in 6 (5%) patients: 2 (1.7%) developed perforations, 3 (2.5%) had colitis and 1 (0.8%) had grade 4 diarrhoea. These adverse events were all reversible following a permanent discontinuation of the MEK inhibitors, or a temporary interruption followed by resumption at a dose lower than conventional posology. There were no fatal outcomes; however one patient had a permanent ileostomy. The mechanism underlying these toxicities is not well known. Clinicians should be aware of such toxicities.

[Large scale teaching in pathology]. / Pédagogie à grande échelle en ACP.

Medical education is currently facing great changes that affect all medical specialties, including anatomical pathology. Due to rapidly increasing medical knowledge and diagnostic complexity, we are living an era of teaching resources mutualization. We present different tools that allow large numbers of students to access courses, self-evaluations, and competencies assessments. MOOC platforms and e-learning platforms are central to these new online tools, which include the French National Platform of Medical Specialties, dedicated to the teaching of 50,000 medical residents in France. We also discuss "serious games" and the use of images and virtual slides in anatomical pathology teaching. These new modalities can deliver essential knowledge to large student populations, but they must be used in conjunction with adapted teacher-led courses focusing on competencies and professional skills in order to be fully effective.

Association of Primary Resistance to Immune Checkpoint Inhibitors in Metastatic Colorectal Cancer With Misdiagnosis of Microsatellite Instability or Mismatch Repair Deficiency Status.

IMPORTANCE: Primary resistance to immune checkpoint inhibitors is observed in 10% to 40% of patients with metastatic colorectal cancer (mCRC) displaying microsatellite instability (MSI) or defective mismatch repair (dMMR). OBJECTIVE: To investigate possible mechanisms underlying primary resistance to immune checkpoint inhibitors of mCRC displaying MSI or dMMR. DESIGN, SETTING, AND PARTICIPANTS: This post hoc analysis of a single-center, prospective cohort included 38 patients with mCRC diagnosed as MSI or dMMR by local laboratories and entered into trials of immune checkpoint inhibitors between January 1, 2015, and December 31, 2016. The accuracy of MSI or dMMR status was also assessed in a retrospective cohort comprising 93 cases of mCRC that were diagnosed as MSI or dMMR between January 1, 1998, and December 31, 2016, in 6 French hospitals. Primary resistance of mCRC was defined as progressive disease according to Response Evaluation Criteria in Solid Tumors criteria, 6 to 8 weeks after initiation of immune checkpoint inhibitors, without pseudo-progression. All tumor samples were reassessed for dMMR status using immunohistochemistry with antibodies directed against MLH1, MSH2, MSH6, and PMS2, and for MSI using polymerase chain reaction with pentaplex markers and with the HSP110 T17 (HT17) repeat. MAIN OUTCOMES AND MEASURES: The primary outcome was positive predictive value. RESULTS: Among the 38 patients (15 women and 23 men; mean [SD] age, 55.6 [13.7] years) in the study with mCRC displaying MSI or dMMR, primary resistance to immune checkpoint inhibitors was observed in 5 individuals (13%). Reassessment of the status of MSI or dMMR revealed that 3 (60%) of these 5 resistant tumors were microsatellite stable or displayed proficient mismatch repair. The positive predictive value of MSI or dMMR status assessed by local laboratories was therefore 92.1% (95% CI, 78.5%-98.0%). In the retrospective cohort of 93 patients (44 women and 49 men; mean [SD] age, 56.8 [18.3] years) without immune checkpoint inhibitor treatment, misdiagnosis of the MSI or dMMR status by local assessment was 10% (n = 9), with a positive predictive value of 90.3% (95% CI, 82.4%-95.0%). Testing for MSI with the HT17 assay confirmed the MSI or dMMR status in 2 of 4 cases showing discrepant results between immunohistochemistry and pentaplex polymerase chain reaction (ie, dMMR but microsatellite stable). CONCLUSIONS AND RELEVANCE: Primary resistance of mCRC displaying MSI or dMMR to immune checkpoint inhibitors is due mainly to misdiagnosis of their MSI or dMMR status. Larger studies are required to confirm these findings. Microsatellite instability or dMMR status should be tested routinely using both immunohistochemistry and polymerase chain reaction methods prior to treatment with immune checkpoint inhibitors.

[A misleading breast metastasis of medullary thyroid carcinoma]. / Métastase mammaire d'un carcinome médullaire thyroïdien : un challenge diagnostique.

Recognition of mammary metastases by pathologists is fundamental because their prognosis and treatment are different from those of primary mammary carcinomas. We report the case of a 54-year-old woman presenting on her mammography a left breast nodule known for 5 years, having discreetly increased in size. Breast ultrasound showed a regular 1.2cm hypoechogenic nodular formation. A microbiopsy was performed. On microscopic examination, we observed a tumor proliferation realizing nests within a small, richly vascularized stroma. The tumor cells had a moderately abundant, eosinophilic, granular cytoplasm and a rounded, slightly atypical nucleus. One mitosis was found for 10 fields at×400 magnification. Tumor cells did not express hormone receptors but chromogranin A, synaptophysin, TTF1 and thyrocalcitonin. The proliferation index established by the anti-Ki67 antibody was 5 %. The diagnosis was a secondary localization of a well-differentiated neuroendocrine tumor which immunohistochemical profile firstly suggests a thyroid origin. We later learned that the patient had a history of total thyroidectomy 13 years ago. It was a sporadic medullary carcinoma of the thyroid. Bone scintigraphy revealed a lacunar lesion of the posterior part of the right iliac wing suspicious of secondary location. This right iliac lesion was biopsied. It was also a localization of the medullary thyroid carcinoma. The final diagnosis is a metastatic medullary thyroid carcinoma, slowly progressive, the mammary metastasis having probably existed for 5 years.

Utility and Safety of Liver Biopsy in Patients with Undetermined Liver Blood Test Anomalies after Allogeneic Hematopoietic Stem Cell Transplantation: A Monocentric Retrospective Cohort Study.

Liver blood test anomalies are common after allogeneic hematopoietic stem cell transplantation (allo-HSCT), but their cause often remains difficult to identify. Our objective was to evaluate the safety and utility of liver biopsies in patients who underwent allo-HSCT. In a retrospective single-center cohort study, we reviewed all cases of patients who underwent liver biopsy between June 2005 and July 2017. During this period, 54 biopsies were performed in 45 patients, in which 38 patients underwent allo-HSCT for malignant and 7 for nonmalignant hematological disorders. Median time between allo-HSCT and liver biopsy was 213 days. Seven biopsies were percutaneous, and 47 were transjugular. No adverse event related to the biopsy procedure occurred; 94.5% biopsies (51 of 54) led to a histological diagnosis. Cholestatic graft-versus-host disease was histologically demonstrated in 16 biopsies (30%); hepatitis-like graft-versus-host disease in 9 biopsies (17%); nonalcoholic steatohepatitis in 6 biopsies (9%); regenerative nodular hyperplasia in 4 biopsies (5%); and drug-induced liver injury, sinusoidal obstruction syndrome, and viral hepatitis each in 3 biopsies (5%). Association between clinical, laboratory, imaging and pathological features was poor. Only 34% of physicians' prebiopsy hypotheses were confirmed by pathological findings. Patient management was influenced by liver biopsy results in 65% of cases, allowing us to identify a new diagnosis (n = 13), rule out a differential diagnosis (n = 14), or confirm the main hypothesis (n = 6). In conclusion, liver biopsy is a safe and useful technique to investigate liver blood test anomalies following allo-HSCT.

First French Pilot Quality Assessment of the EndoPredict Test for Early Luminal Breast Carcinoma.

BACKGROUND/AIM: Genomic signatures are needed for the determination of prognosis in patients with early stage, estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancers. EndoPredict test is a RNA-based multigene assay that assesses the risk of 10-year relapse in this context. Quality assessment is a mandatory requirement for a laboratory to address the analytical quality of these molecular analyses. The aim of the study was to demonstrate the robustness of this prognostic test, its usefulness for the patient's treatment strategy, at the national level. MATERIALS AND METHODS: This study presents a pilot quality assessment (QA) of the EndoPredict test using composite design, including the follow-up of internal control values (qREF) of the 12 genes of the assay for 151 independent tests and one formalin-fixed paraffin embedded (FFPE) breast cancer sample. The evaluation of the test was performed by comparing the results of six independent medical laboratories. RESULTS: All measures were highly reproducible and quantification of the qREF showed a standard deviation of less than 0.50 and a coefficient of variation always of <2%. All laboratories found concordant results for the breast cancer samples. The mean EndoPredict (EP) score for the breast cancer sample was 4.97±0.24. The mean of EPclin score was 3.07±0.05. CONCLUSION: This first French independent reported QA assessed the robustness and reproducibility of the EndoPredict test. Such a simple composite design could represent an adapted QA for an expensive diagnostic test.

18FDG-PET/CT and molecular markers to predict response to neoadjuvant chemotherapy and outcome in HER2-negative advanced luminal breast cancers patients.

BACKGROUND: The efficacy of neoadjuvant chemotherapy regimens in advanced luminal breast cancer patients is difficult to predict. Intrinsic properties of breast tumors, including altered gene expression profile and dynamic evaluation of metabolic properties of tumor cells using positron emission tomography/computed tomography (PET/CT) of tumor cells, have been identified to guide patient's prognosis. The aim of this study is to determine if both analyses may improve the prediction of response to neoadjuvant chemotherapy in ER-positive / HER2-negative breast cancers (BCs) patients. METHODS: We used metabolic PET parameters, at diagnosis and after two cycles of chemotherapy and proliferation gene expression profile on biopsy at diagnosis, in particular, the genomic grade index (GGI) analyzed by reverse transcription and quantitative polymerase chain reaction (RT-qPCR). The pathological response was the surrogate endpoint. RESULTS: The change of FDG uptake between baseline PET and interim PET after 2 cycles of neoadjuvant chemotherapy (ΔSUVmax) was highly associated with pCR (p=0.008). We also observed an ability of P53 mutated status (p=0.042), in addition to histological grade (p=0. 0004), and PR expression (p=0.01) to predict pCR in ER-positive BCs, whereas no proliferation marker predicted pCR (P=0.39 for GGI). Finally, only ΔSUVmax was significantly associated with event free survival (p=0.047). CONCLUSIONS: Our results confirm the predictive and prognostic value of tumor ΔSUVmax in ER-positive /HER2-negative advanced BCs patients. These findings can be helpful to select high-risk patients within trials investigating novel treatment strategies.

COX2/PTGS2 Expression Is Predictive of Response to Neoadjuvant Celecoxib in HER2-negative Breast Cancer Patients.

BACKGROUND: The prognostic and predictive role of cyclo-oxygenase-2 (COX2) in breast cancer is still debated, and in particular, its role as a target of COX2 inhibitor (celecoxib) in neoadjuvant setting. MATERIALS AND METHODS: We analyzed a series of 156 breast cancer samples from patients of the COX2 inhibitor-treated arm included in the REMAGUS-02 randomized phase II trial. COX2 gene expression was assessed by reverse transcription and quantitative polymerase chain reaction using ribonucleic acid from frozen biopsies. Pathological complete response (pCR) was the surrogate end-point. RESULTS: Significantly higher rates of grade 3, and estrogen and progesterone receptor negativity were observed in tumors with the highest expression of COX2. pCR rates were significantly higher in COX2-overexpressing tumors in patients receiving celecoxib. The test for interaction between COX2 gene expression and the celecoxib effect was statistically significant (p<0.01), but was not retained in the multivariate analysis. CONCLUSION: COX2 overexpression is predictive of pCR in patients with celecoxib-treated tumors. The efficacy of celecoxib in breast cancer might be improved by quantification of COX2 gene expression.

Are random biopsies still useful for the detection of neoplasia in patients with IBD undergoing surveillance colonoscopy with chromoendoscopy?

BACKGROUND: Colonoscopy with pan-chromoendoscopy (CE) is superior to standard colonoscopy in detecting neoplasia in patients with IBD. Performing random biopsies in unsuspicious mucosa after CE remains controversial. METHODS: Consecutive patients with IBD who underwent surveillance colonoscopy using CE were prospectively included. The standardised procedure used CE, performed targeted biopsies or endoscopic resection on suspicious lesions and then quadrant random biopsies every 10 cm. A panel of five expert pathologists reviewed histological slides with dysplasia. Logistic regression model was used to evidence the factors associated with neoplasia in any or in random biopsies. RESULTS: 1000 colonoscopes were performed in 1000 patients (495 UC, 505 Crohn's colitis). In 82 patients, neoplasia was detected from targeted biopsies or removed lesions, and among them dysplasia was detected also by random biopsies in 7 patients. Importantly, in 12 additional patients dysplasia was only detected by random biopsies. Overall, 140 neoplastic sites were found in 94 patients, 112 (80%) from targeted biopsies or removed lesions and 28 (20%) by random biopsies. The yield of neoplasia by random biopsies only was 0.2% per-biopsy (68/31 865), 1.2% per-colonoscopy (12/1000) but 12.8% per-patient with neoplasia (12/94). Dysplasia detected by random biopsies was associated with a personal history of neoplasia, a tubular appearing colon and the presence of primary sclerosing cholangitis (PSC). CONCLUSIONS: Despite their low yield, random biopsies should be performed in association with CE in patients with IBD with a personal history of neoplasia, concomitant PSC or a tubular colon during colonoscopy. TRIAL REGISTRATION NUMBER: IRB 001508, Paris 7 University.

Targeting autophagic cancer stem-cells to reverse chemoresistance in human triple negative breast cancer.

There is growing evidence for the role of cancer stem-cells in drug resistance, but with few in situ studies on human tumor samples to decipher the mechanisms by which they resist anticancer agents.Triple negative breast cancer (TNBC) is the most severe sub-type of breast cancer, occurring in younger women and associated with poor prognosis even when treated at a localized stage.We investigated here the relationship between complete pathological response after chemotherapy and breast cancer stem-cell characteristics in pre-treatment biopsies of 78 women with triple negative breast carcinoma (TNBC).We found that chemoresistance was associated with large numbers of breast cancer stem-cells, and that these cancer stem-cells were neither proliferative nor apoptotic, but in an autophagic state related to hypoxia. Using relevant pharmacological models of patient-derived TNBC xenografts, we further investigated the role of autophagy in chemoresistance of breast cancer stem-cells. We demonstrated that hypoxia increased drug resistance of autophagic TNBC stem-cells, and showed that molecular or chemical inhibition of autophagic pathway was able to reverse chemoresistance.Our results support breast cancer stem-cell evaluation in pre-treatment biopsies of TNBC patients, and the need for further research on autophagy inhibition to reverse resistance to chemotherapy.