The E3 ubiquitin ligase TRIP12 is required for pancreatic acinar cell plasticity and pancreatic carcinogenesis.

The E3 ubiquitin ligase thyroid hormone receptor interacting protein 12 (TRIP12) has been implicated in pancreatic adenocarcinoma (PDAC) through its role in mediating the degradation of pancreas transcription factor 1a (PTF1a). PTF1a is a transcription factor essential for the acinar differentiation state that is notably diminished during the early steps of pancreatic carcinogenesis. Despite these findings, the direct involvement of TRIP12 in the onset of pancreatic cancer has yet to be established. In this study, we demonstrated that TRIP12 protein was significantly upregulated in human pancreatic preneoplastic lesions. Furthermore, we observed that TRIP12 overexpression varied within PDAC samples and PDAC-derived cell lines. We further demonstrated that TRIP12 was required for PDAC-derived cell growth and for the expression of E2F-targeted genes. Acinar-to-ductal cell metaplasia (ADM) is a reversible process that reflects the high plasticity of acinar cells. ADM becomes irreversible in the presence of oncogenic Kras mutations and leads to the formation of preneoplastic lesions. Using two genetically modified mouse models, we showed that a loss of TRIP12 prevented acini from developing ADM in response to pancreatic injury. With two additional mouse models, we further discovered that a depletion of TRIP12 prevented the formation of KrasG12D-induced preneoplastic lesions and impaired metastasis formation in the presence of mutated KrasG12D and Trp53R172H genes. In summary our study identified an overexpression of TRIP12 from the early stages of pancreatic carcinogenesis and proposed this E3 ubiquitin ligase as a novel regulator of acinar plasticity with an important dual role in initiation and metastatic steps of PDAC. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Body weight changes and duration of estrogen exposure modulate the evolution of hepatocellular adenomas after contraception discontinuation.

BACKGROUND AND AIMS: The natural history of hepatocellular adenomas (HCAs) remains to be better described, especially in nonresected patients. We aim to identify the predictive factors of HCA evolution after estrogen-based contraception discontinuation. APPROACH AND RESULTS: We retrospectively included patients with a histological diagnosis of HCA from three centers. Clinical, radiological, and pathological data were collected to identify predictive factors of radiological evolution per Response Evaluation Criteria in Solid Tumors, version 1.1, and occurrence of complications (bleeding, malignant transformation). We built a score using variables that modulate estrogen levels: body mass index and duration of estrogen-based contraception. An external cohort was used to validate this score. 183 patients were included in the cohort, including 161 women (89%) using estrogen-based contraception for a median of 12 years. Thirty percent of patients had at least one HNF1A -inactivated HCA, 45.5% at least one inflammatory HCA, and 11% at least one HCA with activation of ß-catenin (bHCA). Twenty-one symptomatic bleedings (11%) and eleven malignant transformations (6%) occurred. Ages < 37 years old ( p = 0.004) and HCA > 5 cm at imaging were independently associated with symptomatic bleeding ( p = 0.003), whereas a bHCA was associated with malignant transformation ( p < 0.001). After a median follow-up of 5 years, radiological regression was observed in 31%, stabilization in 47%, and progression in 22% of patients. Weight loss was associated with regression ( p < 0.0001) and weight gain with progression ( p = 0.02). The estrogen exposure score predicted radiological regression (odds ratio, 2.33; confidence interval 95%, 1.29-4.19; p = 0.005) with a linear relationship between the rate of estrogen exposure and the probability of regression. This result was confirmed in an external cohort of 72 female patients ( p = 0.003). CONCLUSION: Weight variation is strongly associated with radiological evolution after oral contraception discontinuation. A score of estrogen exposure, easily assessable in clinical practice at diagnosis, predicts regression of HCA.

Association of Radiochemotherapy to Immunotherapy in unresectable locally advanced Oesophageal carciNoma-randomized phase 2 trial ARION UCGI 33/PRODIGE 67: the study protocol.

BACKGROUND: In case of locally advanced and/or non-metastatic unresectable esophageal cancer, definitive chemoradiotherapy (CRT) delivering 50 Gy in 25 daily fractions in combination with platinum-based regimen remains the standard of care resulting in a 2-year disease-free survival of 25% which deserves to be associated with new systemic strategies. In recent years, several immune checkpoint inhibitors (anti-PD1/anti-PD-L1, anti-Program-Death 1/anti-Program-Death ligand 1) have been approved for the treatment of various solid malignancies including metastatic esophageal cancer. As such, we hypothesized that the addition of an anti-PD-L1 to CRT would provide clinical benefit for patients with locally advanced oesophageal cancer. To assess the efficacy of the anti-PD-L1 durvalumab in combination with CRT and then as maintenance therapy we designed the randomized phase II ARION (Association of Radiochemotherapy with Immunotherapy in unresectable Oesophageal carciNoma- UCGI 33/PRODIGE 67). METHODS: ARION is a multicenter, open-label, randomized, comparative phase II trial. Patients are randomly assigned in a 1:1 ratio in each arm with a stratification according to tumor stage, histology and centre. Experimental arm relies on CRT with 50 Gy in 25 daily fractions in combination with FOLFOX regimen administrated during and after radiotherapy every two weeks for a total of 6 cycles and durvalumab starting with CRT for a total of 12 infusions. Standard arm is CRT alone. Use of Intensity Modulated radiotherapy is mandatory. The primary endpoint is to increase progression-free survival at 12 months from 50 to 68% (HR = 0.55) (power 90%; one-sided alpha-risk, 10%). Progression will be defined with central external review of imaging. ANCILLARY STUDIES ARE PLANNED: PD-L1 Combined Positivity Score on carcinoma cells and stromal immune cells of diagnostic biopsy specimen will be correlated to disease free survival. The study of gut microbiota will aim to determine if baseline intestinal bacteria correlates with tumor response. Proteomic analysis on blood samples will compare long-term responder after CRT with durvalumab to non-responder to identify biomarkers. CONCLUSION: Results of the present study will be of great importance to evaluate the impact of immunotherapy in combination with CRT and decipher immune response in this unmet need clinical situation. TRIAL REGISTRATION: ClinicalTrials.gov, NCT: 03777813.Trial registration date: 5th December 2018.

CINSARC signature outperforms gold-standard TNM staging and consensus molecular subtypes for clinical outcome in stage II-III colorectal carcinoma.

The outcome of stage II-III colorectal cancer (CRC) is highly variable and therapeutic choice is currently based on TNM staging with a few additional biomarkers. However, studies show that some stage III patients have a better prognosis than some stage II patients. A promising consensus molecular (CMS) classification with prognostic relevance has been developed, but it is not used in daily practice. Our team developed CINSARC, a 67-gene expression prognostic signature, whose prognostic value has been demonstrated in many cancer types. It is applicable to formalin-fixed, paraffin-embedded (FFPE) blocks using NanoString® technology. We investigated whether it could predict outcome in stage II-III CRC. We established the CINSARC classification on the TCGA retrospective cohort comprising 297 stage II-III CRC patients using RNA sequencing and on a second independent cohort comprising 169 cases using NanoString® technology. We compared its recurrence-free and overall survival prognostic value with TNM staging and CMS classification. In the TCGA cohort, we showed that CINSARC significantly splits the population of stage II-III CRC into two groups with different progression-free interval (P = 1.68 × 10-2; HR = 1.87 [1.11-3.16]) and overall survival (P = 3.73 × 10-3; HR = 2.45 [1.31-4.59]) and is a strong prognostic factor in multivariate analysis, outperforming TNM staging and CMS classification. We validated these results in the second cohort by applying CINSARC on FFPE samples with Nanostring® technology. CINSARC is a ready-to-use tool with a robust independent prognostic value in stage II-III CRC.

An unusual phenotype occurs in 15% of mismatch repair-deficient tumors and is associated with non-colorectal cancers and genetic syndromes.

Immunohistochemistry (IHC) and/or MSI-PCR (microsatellite instability-polymerase chain reaction) tests are performed routinely to detect mismatch repair deficiency (MMR-D). Classical MMR-D tumors present a loss of MLH1/PMS2 or MSH2/MSH6 with MSI-High. Other profiles of MMR-D tumors have been described but have been rarely studied. In this study, we established a classification of unusual MMR-D tumors and determined their frequency and clinical impact. All MMR-D tumors identified between 2007 and 2017 were selected. Any profile besides the classical MMR-D phenotype was defined as unusual. For patients with unusual MMR-D tumors, IHC, and PCR data were reviewed, the tumor mutation burden (TMB) was evaluated and clinical and genetic features were collected. Of the 4948 cases of MMR testing, 3800 had both the available IHC and MSI-PCR results and 585 of these had MMR-D. After reviewing the IHC and PCR, 21% of the cases initially identified as unusual MMR-D were reclassified, which resulted in a final identification of 89 unusual MMR-D tumors (15%). Unusual MMR-D tumors were more often associated with non-CRC than classical MMR-D tumors. Unusual MMR-D tumors were classified into four sub-groups: i) isolated loss of PMS2 or MSH6, ii) classical loss of MLH1/PMS2 or MSH2/MSH6 without MSI, iii) four MMR proteins retained with MSI and, iv) complex loss of MMR proteins, with clinical characteristics for each sub-group. TMB-high or -intermediate was shown in 96% of the cancers studied (24/25), which confirmed MMR deficiency. Genetic syndromes were identified in 44.9% (40/89) and 21.4% (106/496) of patients with unusual and classical MMR-D tumors, respectively (P < 0.001). Five patients treated with an immune checkpoint inhibitor (ICI) had a prolonged clinical benefit. Our classification of unusual MMR-D phenotype helps to identify MMR deficiency. Unusual MMR-D phenotype occurs in 15% of MMR-D tumors. A high frequency of genetic syndromes was noted in these patients who could benefit from ICI.

CARMN-NOTCH2 fusion transcript drives high NOTCH2 expression in glomus tumors of the upper digestive tract.

Glomus tumors (GTs) are perivascular tumors mostly occurring in the distal extremities. Rare cases arise in the digestive tract and may be misdiagnosed with neuroendocrine or gastrointestinal stromal tumors. We aimed to specify the features of GT of the upper digestive tract. Clinical, histological, phenotypic, and molecular features of 16 digestive GTs were analyzed, of whom two underwent whole exome and RNA sequencing to search for gene alterations. RNA-sequencing disclosed a t(1:5)(p13;q32) translocation, which resulted in the fusion of CARMN and NOTCH2 in two GTs. The fusion gene encoded a protein sequence corresponding to the NOTCH2 intracellular domain that functions as transcription factor. These finding was supported by high expression of genes targeted by NOTCH. The CARMN-NOTCH2 translocation was detected in 14 out of 16 (88%) GTs of the upper digestive tract; but in only in two out of six cutaneous GTs (33%). Most digestive GT arose from the stomach (n = 13), and the others from duodenal (2) or oesophagous (1). Nuclear expression of NOTCH2 was detected in the 14 cases containing the fusion transcripts. The CARMN-NOTCH2 fusion transcript may contribute to activation of the NOTCH2 pathway in GT and drive tumor development. The high frequency of this translocation in GT of the upper digestive track suggest that detection of nuclear NOTCH2 expression may be useful diagnostic biomarker of these tumors.

MIAmS: microsatellite instability detection on NGS amplicons data.

MOTIVATION: Microsatellite instability (MSI) is a molecular marker of DNA mismatch repair deficiency frequently at play in oncogenesis. MSI testing is used for diagnostic, prognostic and therapeutic purposes in several cancers. The current gold standard analysis for microsatellite status is based on length distribution analysis of multiplex-PCR generated DNA fragments from tumor samples which is a laborious and time consuming method. Next generation sequencing (NGS) using amplicon panels is an easy, accurate and scalable technique to determine both the microsatellite status and tumor genome mutations at the same time. Here, we describe MIAmS, an application designed to tag microsatellite status from amplicon NGS of tumor samples. Interestingly, this tool does not require paired normal tissue for comparison. In addition, this scalable application provides a user-friendly report for the interpretation of the results by biologists and exhibits a strong accuracy and robustness for determination of the MSI status. AVAILABILITY: https://github.com/bialimed/miams. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online, evaluation data are available at http://www.ebi.ac.uk/ena/data/view/PRJEB31725.

Les cancers colorectaux héréditaires vus par le pathologiste.

The pathologist's role in the management of hereditary colorectal cancer is important. The pathologist may suspect a familial cancer when particular morphological and/or clinical criteria are present or give a response to a clinical request in the context of a possible hereditary cancer. In this setting, the pathologist's conclusions have necessarily to be integrated to a precise environment, and if needed, followed by an oncogenetic consultation and a germline mutation research. The aim of this article is to present the main aspects of hereditary colon cancers that a pathologist may see, but also to highlight the histopathological characteristics and the place of the pathologist in the management of these different entities.

Influence of Progenitor-Derived Regeneration Markers on Hepatitis C Virus-Related Cirrhosis Outcome (ANRS CO12 CirVir Cohort).

Progenitor-derived regeneration gives rise to the aberrant expression of biliary markers such as cytokeratin 7 (K7) and epithelial cell adhesion molecule (EpCAM) in hepatocytes. We aimed to describe the expression of these molecules in patients with compensated hepatitis C virus (HCV)-related cirrhosis and to investigate its potential influence on cirrhosis complications. Among patients with Child-Pugh A uncomplicated HCV-related cirrhosis enrolled in the prospective ANRS CO12 CirVir cohort, we selected individuals with a liver biopsy collected within 2 years before inclusion in the study. K7 and EpCAM immunostaining identified intermediate hepatobiliary cells. The influence of biliary marker expres-sion in hepatocytes on decompensation events and the occurrence of hepatocellular carcinoma (HCC) was studied using a multivariate Cox proportional hazards regression model. Among the 337 patients eligible for the study (men, 67%; median age, 52 years), 198 (58.8%) had biopsies with K7-positive hepatocytes including extensive staining in 40 (11.9%) and 203 had EpCAM-positive hepatocytes (60.6%). During follow-up (median, 54.2 months), 47 patients (14%) experienced a decompensation event, and HCC was diagnosed in 37 patients (11%). Extensive K7 staining was independently associated with the occurrence of a decompensation event (hazard ratio [HR], 3.00; 95% confidence interval [CI], 1.30-6.89; P = 0.010). EpCAM expression was independently associated with HCC occurrence (HR, 2.37; 95% CI, 1.07-5.23; P =0.033) along with age and a low prothrombin ratio. CONCLUSION: Progenitor-derived regeneration depicted by K7 and EpCAM immunostaining of hepatocytes in liver biopsies of patients with compensated HCV-related cirrhosis marks a cirrhosis stage more prone to develop complications. (HEPATOLOGY 2018; 68:1534-1548).

Correction: Protein biomarkers predictive for response to anti-EGFR treatment in RAS wild-type metastatic colorectal carcinoma.

Supplementary Table 1 and the Supplementary Figure legends were not included when this manuscript was first published. The files are now available here.

Molecular Classification of Hepatocellular Adenoma Associates With Risk Factors, Bleeding, and Malignant Transformation.

BACKGROUND & AIMS: Hepatocellular adenomas (HCAs) are benign liver tumors that can be assigned to molecular subtypes based on inactivating mutations in hepatocyte nuclear factor 1A, activating mutations in ß-catenin, or activation of inflammatory signaling pathways. We aimed to update the classification system for HCA and associate the subtypes with disease risk factors and complications. METHODS: We analyzed expression levels of 20 genes and sequenced exon regions of 8 genes (HNF1A, IL6ST, CTNNB1, FRK, STAT3, GNAS, JAK1, and TERT) in 607 samples of 533 HCAs from 411 patients, collected from 28 centers mainly in France from 2000 and 2014. We performed gene expression profile, RNA sequence, whole-exome and genome sequence, and immunohistochemical analyses of select samples. Molecular data were associated with risk factors, histopathology, bleeding, and malignant transformation. RESULTS: Symptomatic bleeding occurred in 14% of the patients (85% of cases were female, median age, 38 years); 7% of the nodules were borderline between HCA and hepatocellular carcinoma, and 3% of patients developed hepatocellular carcinoma from HCA. Based on molecular features, we classified HCA into 8 subgroups. One new subgroup, composed of previously unclassified HCA, represented 4% of HCAs overall and was associated with obesity and bleeding. These tumors were characterized by activation of sonic hedgehog signaling, due to focal deletions that fuse the promoter of INHBE with GLI1. Analysis of genetic heterogeneity among multiple HCAs, from different patients, revealed a molecular subtype field effect; multiple tumors had different mutations that deregulated similar pathways. Specific molecular subtypes of HCA associated with various HCA risk factors, including imbalances in estrogen or androgen hormones. Specific molecular subgroup of HCA with ß-catenin and sonic hedgehog activation associated with malignant transformation and bleeding, respectively. CONCLUSIONS: Using sequencing and gene expression analyses, we identified a subgroup of HCA characterized by fusion of the INHBE and GLI1 genes and activation of sonic hedgehog pathway. Molecular subtypes of HCAs associated with different patients' risk factors for HCA, disease progression, and pathology features of tumors. This classification system might be used to select treatment strategies for patients with HCA.

CCDC115-CDG: A new rare and misleading inherited cause of liver disease.

Congenital disorders of glycosylation (CDG) linked to defects in Golgi apparatus homeostasis constitute an increasing part of these rare inherited diseases. Among them, COG-CDG, ATP6V0A2-CDG, TMEM199-CDG and CCDC115-CDG have been shown to disturb Golgi vesicular trafficking and/or lumen pH acidification. Here, we report 3 new unrelated cases of CCDC115-CDG with emphasis on diagnosis difficulties related to strong phenotypic similarities with mitochondriopathies, Niemann-Pick disease C and Wilson Disease. Indeed, while two individuals clinically presented with early and severe liver fibrosis and cirrhosis associated with neurological symptoms, the other one "only" showed isolated and late severe liver involvement. Biological results were similar to previously described patients, including hypercholesterolemia, elevated alkaline phosphatases and defects in copper metabolism. CDG screening and glycosylation study finally led to the molecular diagnosis of CCDC115-CDG. Besides pointing to the importance of CDG screening in patients with unexplained and severe liver disease, these reports expand the clinical and molecular phenotypes of CCDC115-CDG. The hepatic involvement is particularly addressed. Furthermore, hypothesis concerning the pathogenesis of the liver disease and of major biological abnormalities are proposed.

[Guidelines for the management of malignant colo-rectal polyps (pTis and pT1) treated by endoscopic resection]. / Protocole d'examen d'un polype colorectal pTis/pT1 traité par exérèse endoscopique.

The therapeutic management of malignant colorectal polyp with endoscopic resection is mainly based on specific histopathological criteria. The quality of these criteria is strongly linked to the management of the endoscopic specimen. The French Pathology Society drafted a standardized pathological report with guidelines for the macroscopic management of the endoscopic specimen and explanatory notes for each histopathological criteria. These guidelines are based on the TNM AJCC/UICC classification, 8th edition and the WHO 2010 classification of colorectal tumors, the recommendations of the French Society of Digestive Endoscopy, the synthesis of the literature and on international consensus for prognostic criteria. The pathological report of a malignant colorectal polyp must clearly mention: the histological type and the size of the polyp, the pT stage and the following five prognostic criteria: the value of the resection margins, the level of tumor invasion into the submucosa, the grade of the tumor, the absence or presence of vascular emboli and of tumor budding.

Protein biomarkers predictive for response to anti-EGFR treatment in RAS wild-type metastatic colorectal carcinoma.

BACKGROUND: Metastatic colorectal cancer (mCRC) patients with mutant KRAS or NRAS are ineligible for anti-epidermal growth factor receptor (anti-EGFR) therapy, as RAS mutations activate downstream pathways independently of EGFR and induce primary resistance. However, even among RAS wild-type (WT) patients, only a fraction responds to anti-EGFR therapy, suggesting that other mechanisms of resistance exist. We hypothesise that different (epi)genetic alterations can lead to primary anti-EGFR resistance and that the crucial end point is the activation of protein signalling pathways. METHODS: We analysed the expression and activation of proteins involved in cell signalling, using reverse phase protein arrays, on a multicentre French cohort of RAS WT mCRC treated with anti-EGFR treatment. RESULTS: We identify activated EGFR and HER3 as protein biomarkers predictive for better overall survival. Active EGFR signalling and downstream PI3K, but not MAPK, pathway activation are associated with response to anti-EGFR treatment. Left-sided mCRC displays active ErbB2/3 and Wnt pathways and a better response to anti-EGFR therapy compared to right-sided mCRC. CONCLUSIONS: We identify active EGFR and PI3K signalling as a key factor for response to anti-EGFR treatment in mCRC and highlight the importance of developing these biomarkers in clinical practice for the selection of RAS WT mCRC patients that would benefit from anti-EGFR treatment.

Detection of viral hepatitis E in clinical liver biopsies.

AIMS: To determine the relative utility of in-situ testing for hepatitis E virus (HEV) RNA and paraffin-section polymerase chain reaction (PCR) to diagnose HEV infection in paraffin-embedded clinical liver biopsies, and to correlate with clinicopathological characteristics. METHODS AND RESULTS: We evaluated in-situ and quantitative PCR (qPCR)-based approaches to identifying HEV in clinical liver biopsies from infected patients from multiple centres, correlating with clinical setting (immunocompetent, allograft or immunosuppressed native liver) and histological findings. Thirty-six biopsies from 29 patients had histological data, 27 and 23 of which had satisfactory material for in-situ RNA testing and tissue qPCR, respectively. Both approaches specifically identified HEV infection, but tissue qPCR was significantly more sensitive than RNAscope in-situ testing (P = 0.035). In immunocompetent but not immunosuppressed patients the tissue qPCR yield correlated with the severity of lobular hepatitis (rho = 0.94, P < 0.001). qPCR viral yield was comparably high in allografts and immunosuppressed native livers and significantly greater than with native liver infection. Immunosuppressed patients showed reduced severity of hepatitis and cholestatic changes, compared with immunocompetent patients. Indeed, HEV-infected liver allografts could show minimal hepatitis for many months. In individual cases each technique was useful when serum was not available to identify chronic infection retrospectively (in biopsies taken 4-31 months before diagnosis), to identify persistent/residual infection when contemporary serum PCR was negative and to identify cleared infection. CONCLUSIONS: qPCR is more effective than in-situ RNA testing to identify HEV infection in paraffin-embedded liver biopsies and has diagnostic utility in selected settings.

HSP110 T17 simplifies and improves the microsatellite instability testing in patients with colorectal cancer.

BACKGROUND: Every colorectal cancer (CRC) patient should be tested for microsatellite instability (MSI, a marker for defective DNA mismatch repair) as a first screen for Lynch syndrome (LS). In this study, we investigated whether it may be possible to improve the detection of MSI in CRC. We examined whether the HT17 DNA repeat (critical for correct splicing of the chaperone HSP110) might constitute a superior marker for diagnosis of the MSI phenotype in patients with CRC compared with the standard panel of markers (pentaplex). METHODS: The HT17 polymorphism was analysed in germline DNA from 1037 multi-ethnic individuals. We assessed its sensitivity and specificity for detecting MSI in a multicentre, population-based cohort of 685 patients with CRC and an additional series of 70 patients with CRC considered to be at-risk of LS. All cases were screened earlier for MSI using pentaplex markers. Cases showing discordant HT17/pentaplex results were further examined for the expression of mismatch repair proteins. RESULTS: HT17 status was analysed independently and blinded to previous results from pentaplex genotyping. HT17 showed no germline allelic variation outside a very narrow range. Compared with the pentaplex panel, HT17 showed better sensitivity (0.984 (95% CI 0.968 to 0.995) vs 0.951 (95% CI 0.925 to 0.972)) and similar specificity (0.997 (95% CI 0.989 to 1.000) for both) for the detection of MSI. Furthermore, HT17 alone correctly classified samples judged to be uncertain with the pentaplex panel and showed excellent ability to detect MSI in patients with LS. CONCLUSIONS: HT17 simplifies and improves the current standard molecular methods for detecting MSI in CRC.

Patients with colorectal tumors with microsatellite instability and large deletions in HSP110 T17 have improved response to 5-fluorouracil­based chemotherapy.

BACKGROUND & AIMS: Patients with colorectal tumors with microsatellite instability (MSI) have better prognoses than patients with tumors without MSI, but have a poor response to 5-fluorouracil­based chemotherapy. A dominant-negative form of heat shock protein (HSP)110 (HSP110DE9) expressed by cancer cells with MSI, via exon skipping caused by somatic deletions in the T(17) intron repeat, sensitizes the cells to 5-fluorouracil and oxaliplatin.We investigated whether HSP110 T(17) could be used to identify patients with colorectal cancer who would benefit from adjuvant chemotherapy with 5-fluorouracil and oxaliplatin. METHODS: We characterized the interaction between HSP110 and HSP110DE9 using surface plasmon resonance. By using polymerase chain reaction and fragment analysis, we examined how the size of somatic allelic deletions in HSP110 T(17) affected the HSP110 protein expressed by tumor cells. We screened 329 consecutive patients with stage II­III colorectal tumors with MSI who underwent surgical resection at tertiary medical centers for HSP110 T(17). RESULTS: HSP110 and HSP110DE9 interacted in a1:1 ratio. Tumor cells with large deletions in T(17) had increased ratios of HSP110DE9:HSP110, owing to the loss of expression of full-length HSP110. Deletions in HSP110 T(17) were mostly biallelic in primary tumor samples with MSI. Patients with stage II­III cancer who received chemotherapy and had large HSP110 T(17) deletions (≥5 bp; 18 of 77 patients, 23.4%) had longer times of relapse-free survival than patients with small or no deletions (≤4 bp; 59 of 77 patients, 76.6%) in multivariate analysis (hazard ratio, 0.16; 95% confidence interval, 0.012­0.8; P = .03). We found a significant interaction between chemotherapy and T17 deletion (P =.009). CONCLUSIONS: About 25% of patients with stages II­III colorectal tumors with MSI have an excellent response to chemotherapy, due to large, biallelic deletions in the T(17) intron repeat of HSP110 in tumor DNA.

Endoscopic ultrasound-guided fine-needle aspiration biopsy coupled with a KRAS mutation assay using allelic discrimination improves the diagnosis of pancreatic cancer.

GOALS AND BACKGROUND: Mutation of the KRAS oncogene is present in 75% to 95% of pancreatic cancer tissues. This study aimed to evaluate whether endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), combined with analysis of the KRAS mutation, improves the diagnosis of pancreatic cancer in cases of inconclusive or doubtful cytopathologic analysis. PATIENTS AND METHODS: We prospectively included 186 patients with a pancreatic mass (103 men; mean age: 62 y). Cytopathology and KRAS mutations, using TaqMan MGB allelic discrimination, were performed on EUS-FNA material. A final diagnosis was obtained from EUS-FNA analysis and/or a subsequent biopsy if necessary, and/or surgery, and follow-up: these were pancreatic adenocarcinoma (n=104), other malignant pancreatic tumors (n=22), and benign lesions (n=60, including 35 cases of chronic pancreatitis). RESULTS: Inconclusive or doubtful (low-grade dysplasia or atypia) cytopathology was found in 68 cases. Of these, 29 patients who had adenocarcinoma were subsequently diagnosed, including 19 cases with a former KRAS mutation. Sensitivity, specificity, positive and negative predictive values, and overall accuracy of cytopathology alone to diagnose adenocarcinoma were 73%, 100%, 100%, 75%, and 85%, respectively. When KRAS mutation analysis was combined with pathology, these values reached 88%, 99%, 99%, 89%, and 93%, respectively. The performance of EUS-FNA to diagnose malignancy was similarly improved after the KRAS-mutation assay (negative predictive value increased from 67% to 88%; accuracy increased from 85% to 94%). CONCLUSIONS: EUS-FNA plus KRAS-mutation analysis, using allelic discrimination, is accurate and improves the diagnosis of pancreatic adenocarcinoma when pathology is inconclusive or doubtful.