Colorectal polypectomy and endoscopic mucosal resection: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2024.

1: ESGE recommends cold snare polypectomy (CSP), to include a clear margin of normal tissue (1-2 mm) surrounding the polyp, for the removal of diminutive polyps (≤ 5 mm).Strong recommendation, high quality of evidence. 2: ESGE recommends against the use of cold biopsy forceps excision because of its high rate of incomplete resection.Strong recommendation, moderate quality of evidence. 3: ESGE recommends CSP, to include a clear margin of normal tissue (1-2 mm) surrounding the polyp, for the removal of small polyps (6-9 mm).Strong recommendation, high quality of evidence. 4: ESGE recommends hot snare polypectomy for the removal of nonpedunculated adenomatous polyps of 10-19 mm in size.Strong recommendation, high quality of evidence. 5: ESGE recommends conventional (diathermy-based) endoscopic mucosal resection (EMR) for large (≥ 20 mm) nonpedunculated adenomatous polyps (LNPCPs).Strong recommendation, high quality of evidence. 6: ESGE suggests that underwater EMR can be considered an alternative to conventional hot EMR for the treatment of adenomatous LNPCPs.Weak recommendation, moderate quality of evidence. 7: Endoscopic submucosal dissection (ESD) may also be suggested as an alternative for removal of LNPCPs of ≥ 20 mm in selected cases and in high-volume centers.Weak recommendation, low quality evidence. 8: ESGE recommends that, after piecemeal EMR of LNPCPs by hot snare, the resection margins should be treated by thermal ablation using snare-tip soft coagulation to prevent adenoma recurrence.Strong recommendation, high quality of evidence. 9: ESGE recommends (piecemeal) cold snare polypectomy or cold EMR for SSLs of all sizes without suspected dysplasia.Strong recommendation, moderate quality of evidence. 10: ESGE recommends prophylactic endoscopic clip closure of the mucosal defect after EMR of LNPCPs in the right colon to reduce to reduce the risk of delayed bleeding.Strong recommendation, high quality of evidence. 11: ESGE recommends that en bloc resection techniques, such as en bloc EMR, ESD, endoscopic intermuscular dissection, endoscopic full-thickness resection, or surgery should be the techniques of choice in cases with suspected superficial invasive carcinoma, which otherwise cannot be removed en bloc by standard polypectomy or EMR.Strong recommendation, moderate quality of evidence.

Long-Term Follow-up of the Italian Flexible Sigmoidoscopy Screening Trial.

BACKGROUND: Recent reports showed that the protective effect of flexible sigmoidoscopy (FS) screening was maintained up to17 years, although differences were reported by sex. OBJECTIVE: To assess long-term reduction of colorectal cancer (CRC) incidence and mortality after a single FS screening. DESIGN: Parallel randomized controlled trial. (ISRCTN registry number: 27814061). SETTING: 6 centers in Italy. PARTICIPANTS: Persons aged 55 to 64 years expressing interest in having FS screening if invited, recruited from 1995 to 1999 and followed until 2012 (incidence) and 2014 to 2016 (mortality). INTERVENTION: Eligible persons were randomly assigned (1:1 ratio) to either the once-only FS screening group or control (usual care) group. MEASUREMENTS: Incidence and mortality rate ratios (RRs) and rate differences. RESULTS: A total of 34 272 persons (17 136 in each group) were included in the analysis; 9911 participants had screening in the intervention group. Median follow-up was 15.4 years for incidence and 18.8 years for mortality. Incidence of CRC was reduced by 19% (RR, 0.81 [95% CI, 0.71 to 0.93]) in the intention-to-treat (ITT) analysis, comparing the intervention with the control group, and by 33% (RR, 0.67 [CI, 0.56 to 0.81]) in the per protocol (PP) analysis, comparing participants screened in the intervention group with the control persons. Colorectal cancer mortality was reduced by 22% (RR, 0.78 [CI, 0.61 to 0.98]) in the ITT analysis and by 39% (RR, 0.61 [CI, 0.44 to 0.84]) in the PP analysis. Incidence of CRC was statistically significantly reduced among both men and women. Colorectal cancer mortality was statistically significantly reduced among men (ITT RR, 0.73 [CI, 0.54 to 0.97]) but not among women (ITT RR, 0.90 [CI, 0.59 to 1.37]). LIMITATION: Self-selection of volunteers from the general population sample targeted for recruitment may limit generalizability. CONCLUSION: The strong protective effect of a single FS screening for CRC incidence and mortality was maintained up to 15 and 19 years, respectively. PRIMARY FUNDING SOURCE: Italian Association for Cancer Research, Italian National Research Council, Istituto Oncologico Romagnolo, Fondo "E. Tempia," University of Milan, and Local Health Unit ASL-Torino.

Telocytes are the physiological counterpart of inflammatory fibroid polyps and PDGFRA-mutant GISTs.

PDGFRA mutations in the gastrointestinal (GI) tract can cause GI stromal tumour (GIST) and inflammatory fibroid polyp (IFP). Hitherto no cell type has been identified as a physiological counterpart of the latter, while interstitial Cajal cells (ICC) are considered the precursor of the former. However, ICC hyperplasia (ICCH), which strongly supports the ICC role in GIST pathogenesis, has been identified in germline KIT-mutant settings but not in PDGFRA-mutant ones, challenging the precursor role of ICC for PDGFRA-driven GISTs. Telocytes are a recently described interstitial cell type, CD34+/PDGFRA+. Formerly considered fibroblasts, they are found in many organs, including the GI tract where they are thought to be involved in neurotransmission. Alongside IFPs and gastric GISTs, GI wall "fibrosis" has been reported in germline PDGFRA-mutants. Taking the opportunity offered by its presence in a germline PDGFRA-mutant individual, we demonstrate that this lesion is sustained by hyperplastic telocytes, constituting the PDGFRA-mutant counterpart of germline KIT mutation-associated ICCH. Moreover, our findings support a pathogenetic relationship between telocyte hyperplasia and both IFPs and PDGFRA-mutant GISTs. We propose the term "telocytoma" for defining IFP, as it conveys both the pathogenetic (neoplastic) and histotypic ("telocytary") essence of this tumour, unlike IFP, which rather evokes an inflammatory-hyperplastic lesion.

Assessment of a HER2 scoring system for colorectal cancer: results from a validation study.

We sought to develop criteria for ERBB2-positivity (HER2) in colorectal cancer to ensure accurate identification of ERBB2-amplified metastatic colorectal cancer patients suitable for enrollment in a phase II trial of ERBB2-targeted therapy (HERACLES trial). A two-step approach was used. In step 1, a consensus panel of pathologists adapted existing protocols for use in colorectal cancer to test ERBB2 expression and amplification. Collegial revision of an archival test cohort of colorectal cancer samples led to specific recommendations for adapting current breast and gastric cancer criteria for scoring ERBB2 in colorectal cancer. In step 2, from September 2012 to January 2015, colorectal-specific ERBB2 testing protocols and ERBB2 scoring criteria were used to centrally screen for ERBB2-positive KRAS wild-type colorectal cancer patients to be enrolled in the HERACLES trial (clinical validation cohort). In both archival test (N=256) and clinical validation (N=830) cohorts, a clinically sizeable 5% fraction of KRAS wild-type colorectal cancer patients was found to be ERBB2-positive according to the colorectal cancer-specific ERBB2 scoring criteria. ERBB2-positive tumors showed ERBB2 immunostaining consisting of intense membranous ERBB2 protein expression, corresponding to homogenous ERBB2 amplification, in >50% of cells. None of the immunohistochemistry 0 or 1+ cases was amplified. Concordance between SISH and FISH was 100%. In conclusion, we propose specific criteria for defining ERBB2-positivity in colorectal cancer (HERACLES Diagnostic Criteria). In a phase II trial of trastuzumab and lapatinib in a cetuximab-resistant population, HERACLES Diagnostic Criteria shaped the selection of patients and defined ERBB2 as a predictive marker for response to ERBB2-targeted therapy in metastatic colorectal cancer.

Histological features of advanced colorectal adenomas detected by endoscopy and fecal immunochemical test.

BACKGROUND AND STUDY AIMS: The detection of advanced adenomas within organized screening programs using either immunochemical fecal occult blood test (FIT) or endoscopy has been associated with the prevention of colorectal cancer. The histological changes and pathogenetic mechanisms that lead to the detection of such lesions by either of these screening methods have not yet been addressed. PATIENTS AND METHODS: The histological specimens of 50 advanced adenomas detected by FIT were compared with those of 50 advanced adenomas detected by primary endoscopy screening that were matched for size and histology. The following variables were systematically recorded: 1) histopathological changes compatible with luminal bleeding induced by ischemia; 2) hypoxia in the adenomatous tissue, assessed through the expression of carbonic anhydrase IX; and 3) microvessel quantitative analysis, evaluated by CD31 and CD105 immunostains. All specimens were reviewed blindly by an expert gastrointestinal pathologist. RESULTS: Histopathological changes associated with ischemia-related luminal bleeding were significantly more frequent in FIT-positive than in endoscopy-detected advanced adenomas (78 % vs. 14 %; P < 0.001). Carbonic anhydrase IX expression was also significantly higher in FIT-detected advanced adenomas (immunohistochemical score: 12.0 vs. 4.1; P < 0.001). Conversely, no differences were found in microvessel density. CONCLUSIONS: The detection of advanced adenomas by FIT screening appears to be related to ischemia-associated luminal bleeding, which, in turn, may be due to periods of hypoxia. The absence of such changes in endoscopy-detected advanced adenomas would suggest that the two screening methods may be complementary for the detection of advanced neoplasia within organized screening programs.

Blood and lymphatic vessel invasion in pT1 colorectal cancer: an international concordance study.

AIM: This study was performed to evaluate the concordance in pathological assessments of blood and lymphatic vessel invasion (BLI) in pT1 colorectal cancers and to assess the effect of diagnostic criterion on consistency in the assessment of BLI. METHODS: Forty consecutive patients undergoing surgical resection of pT1 colorectal cancers were entered into this study. H&E-stained, D2-40-stained and elastica-stained slides from the tumours were examined by 18 pathologists from seven countries. The 40 cases were divided into two cohorts with 20 cases each. In cohort 1, pathologists diagnosed BLI using criteria familiar to them; all Japanese pathologists used a criterion of BLI from the Japanese Society for Cancer of the Colon and Rectum (JSCCR). In cohort 2, all pathologists used the JSCCR diagnostic criterion. RESULTS: In cohort 1, diagnostic concordance was moderate in the US/Canadian and European pathologists. There were no differences in the consistency compared with results for Japanese pathologists, and no improvement in the diagnostic concordance was found for using the JSCCR criterion. However, in cohort 2, the JSCCR criterion decreased the consistency of BLI diagnosis in the US/Canadian and European pathologists. The level of decreased consistency in the assessment of BLI was different between the US/Canadian and European pathologists. CONCLUSIONS: A uniform criterion strongly influences the diagnostic consistency of BLI but may not always improve the concordance. Further study is required to achieve an objective diagnosis of BLI in colorectal cancer. The varying effects of diagnostic criterion on the pathologists from Japan, the USA/Canada and Europe might reflect varied interpretations of the criterion. Internationally accepted criterion should be developed by participants from around the world.

YKL-40/c-Met expression in rectal cancer biopsies predicts tumor regression following neoadjuvant chemoradiotherapy: a multi-institutional study.

BACKGROUND: Neoadjuvant chemo-radiotherapy (CRT) followed by surgical resection is the standard treatment for locally advanced rectal cancer, although complete tumor pathological regression is achieved in only up to 30% of cases. A clinicopathological and molecular predictive stratification of patients with advanced rectal cancer is still lacking. Here, c-Met and YKL-40 have been studied as putative predictors of CRT response in rectal cancer, due to their reported involvement in chemoradioresistance in various solid tumors. MATERIAL AND METHODS: A multicentric study was designed to assess the role of c-Met and YKL-40 expression in predicting chemoradioresistance and to correlate clinical and pathological features with CRT response. Immunohistochemistry and fluorescent in situ hybridization for c-Met were performed on 81 rectal cancer biopsies from patients with locally advanced rectal adenocarcinoma. All patients underwent standard (50.4 gy in 28 fractions + concurrent capecitabine 825 mg/m2) neoadjuvant CRT or the XELOXART protocol. CRT response was documented on surgical resection specimens and recorded as tumor regression grade (TRG) according to the Mandard criteria. RESULTS: A significant correlation between c-Met and YKL-40 expression was observed (R = 0.43). The expressions of c-Met and YKL-40 were both significantly associated with a lack of complete response (86% and 87% of c-Met and YKL-40 positive cases, p< 0.01 and p = 0.006, respectively). Thirty of the 32 biopsies co-expressing both markers had partial or absent tumor response (TRG 2-5), strengthening their positive predictive value (94%). The exclusive predictive role of YKL-40 and c-Met was confirmed using a multivariate analysis (p = 0.004 and p = 0.007 for YKL-40 and c-Met, respectively). TRG was the sole morphological parameter associated with poor outcome. CONCLUSION: c-Met and YKL-40 expression is a reliable predictor of partial/absent response to neoadjuvant CRT in rectal cancer. Targeted therapy protocols could take advantage of prior evaluations of c-MET and YKL-40 expression levels to increase therapeutic efficacy.

Aurora kinase A gene copy number is associated with the malignant transformation of colorectal adenomas but not with the serrated neoplasia progression.

A crucial role for Aurora Kinase A (AURKA) gene has been demonstrated in the advanced steps of colorectal tumor progression. Little is known, however, about its role in the early phases of the adenoma-carcinoma sequence. Moreover, no data are currently available concerning AURKA involvement in the serrated tumorigenesis. Fluorescence in situ hybridization analysis and immunohistochemistry were used to assess gene copy number and protein expression in 40 colorectal adenomas, 20 cancerized adenomas, and 20 serrated polyps. An increased copy number was found either in adenomatous tissue or in early cancer in the vast majority of cancerized adenomas, but only in 5% of adenomas (P < .001). Protein expression strictly paralleled fluorescence in situ hybridization results. No changes in the gene copy number were observed in serrated polyps, regardless of their histotype and the presence of dysplasia, even if high percentages of immunostained cells were detected in all the subgroups. AURKA gene is associated with progressive colorectal adenomas but is uninvolved in the development of nonprogressive adenomas. The diploid status of the gene is maintained along the progression of serrated neoplasia. AURKA protein expression in serrated polyps is uncoupled from gene status and is likely to reflect apoptotic dysregulation.

Early rectal cancer: the European Association for Endoscopic Surgery (EAES) clinical consensus conference.

BACKGROUND: The last 30 years have witnessed a significant increase in the diagnosis of early-stage rectal cancer and the development of new strategies to reduce the treatment-related morbidity. Currently, there is no consensus on the definition of early rectal cancer (ERC), and the best management of ERC has not been yet defined. The European Association for Endoscopic Surgery in collaboration with the European Society of Coloproctology developed this consensus conference to provide recommendations on ERC diagnosis, staging and treatment based on the available evidence. METHODS: A multidisciplinary group of experts selected on their clinical and scientific expertise was invited to critically review the literature and to formulate evidence-based recommendations by the Delphi method. Recommendations were discussed at the plenary session of the 14th World Congress of Endoscopic Surgery, Paris, 26 June 2014, and then posted on the EAES website for open discussion. RESULTS: Tumour biopsy has a low accuracy. Digital rectal examination plays a key role in the pre-operative work-up. Magnification chromoendoscopy, endoscopic ultrasound and magnetic resonance imaging are complementary staging modalities. Endoscopic submucosal dissection and transanal endoscopic microsurgery are the two established approaches for local excision (LE) of selected ERC. The role of all organ-sparing approaches including neoadjuvant therapies followed by LE should be formally assessed by randomized controlled trials. Rectal resection and total mesorectal excision is indicated in the presence of unfavourable features at the pathological evaluation of the LE specimen. The laparoscopic approach has better short-term outcomes and similar oncologic results when compared with open surgery. CONCLUSIONS: The management of ERC should always be based on a multidisciplinary approach, aiming to increase the rate of organ-preserving procedures without jeopardizing survival.

Tumour budding is associated with hypoxia at the advancing front of colorectal cancer.

AIMS: The tumour budding ability to predict cancer progression is felt to be worthy of investigation with regard to its biological properties. This study was aimed at evaluating the role of hypoxia and microvascularization in the morphogenesis of tumour budding in colorectal carcinoma. METHODS AND RESULTS: The immunohistochemical expression of hypoxia-inducible factor-1α (HIF-1α) and carbonic anhydrase IX in cancer cells and CD105 in carcinoma-induced microvascularization were assessed in 479 colorectal cancers. Furthermore, MET proto-oncogene, receptor tyrosine kinase (MET) gene amplification was searched using fluorescence in-situ hybridization (FISH). Carbonic anhydrase IX and HIF-1α overall scores differed significantly in low- compared to high-grade tumour budding cancers (P < 0.001), both in pT1 and in pT2-4 tumours. Intratumour analysis of budding foci showed a striking absence of carbonic anhydrase IX immunostain in detaching cells with respect to the surrounding microsectors. The mean microvessel density values were significantly higher in the low- compared to the high-grade tumour budding groups (P < 0.001). A similar copy number of MET gene was detected in the two groups. CONCLUSIONS: Our study shows that tumour budding is associated with hypoxia induced by hypovascularization at the advancing front of colorectal cancer and that budding cells express a HIF-1α-mediated hypoxic tumour phenotype. MET gene amplification is not related to tumour budding morphogenesis.

The growing complexity of the intestinal polyposis syndromes.

Familial adenomatous polyposis has been the first form of inherited intestinal polyposis to be recognized. For a long time it has been considered the main polyposis syndrome, associated with an easily recognizable phenotype, with a marginal role attributed to a few very rare hamartomatous conditions. More recently, it has been gradually demonstrated that the intestinal polyposes encompass a range of conditions within a wide spectrum of disease severity, polyp histology, and extraintestinal manifestations. A growing number of genes and phenotypes has been identified, and heterogeneity of somatic molecular pathways underlying epithelial transformation in different syndromes and associated tumors has been documented. Increasing knowledge on the molecular bases and more widespread use of genetic tests has shown phenotypic overlaps between conditions that were previously considered distinct, highlighting diagnostic difficulties. With the advent of next generation sequencing, the diagnosis and the classification of these syndromes will be progressively based more on genetic testing results. However, the phenotypic variability documented among patients with mutations in the same genes cannot be fully explained by different expressivity, indicating a role for as yet unknown modifying factors. Until the latter will be identified, the management of patients with polyposis syndromes should be guided by both clinical and genetic findings.

Oxidative DNA damage drives carcinogenesis in MUTYH-associated-polyposis by specific mutations of mitochondrial and MAPK genes.

MUTYH is a DNA-base-excision-repair gene implicated in the activation of nuclear and mitochondrial cell-death pathways. MUTYH germline mutations cause an inherited polyposis, MUTYH-associated-polyposis, characterized by multiple adenomas and increased susceptibility to colorectal cancer. Since this carcinogenesis remains partially unknown, we searched for nuclear and mitochondrial gene alterations that may drive the tumorigenic process. Ninety-six adenomas and 7 carcinomas from 12 MUTYH-associated-polyposis and 13 classical/attenuated adenomatous polyposis patients were investigated by sequencing and pyrosequencing for the presence of mutations in KRAS, BRAF, MT-CO1/MT-CO2 and MT-TD genes. KRAS mutations were identified in 24% MUTYH-associated-polyposis vs 15% classical/attenuated familial polyposis adenomas; mutated MUTYH-associated-polyposis adenomas exhibited only c.34G>T transversions in codon 12, an alteration typically associated with oxidative DNA damage, or mutations in codon 13; neither of these mutations was found in classical/attenuated familial polyposis adenomas (P<0.001). Mutated MUTYH-associated-polyposis carcinomas showed KRAS c.34G>T transversions, prevalently occurring with BRAFV600E; none of the classical/attenuated familial polyposis carcinomas displayed these alterations. Comparing mitochondrial DNA from lymphocytes and adenomas of the same individuals, we detected variants in 82% MUTYH-associated-polyposis vs 38% classical/attenuated familial polyposis patients (P=0.040). MT-CO1/MT-CO2 missense mutations, which cause aminoacid changes, were only found in MUTYH-associated-polyposis lesions and were significantly associated with KRAS mutations (P=0.0085). We provide evidence that MUTYH-associated-polyposis carcinogenesis is characterized by the occurrence of specific mutations in both KRAS and phylogenetically conserved genes of mitochondrial DNA which are involved in controlling oxidative phosphorylation; this implies the existence of a colorectal tumorigenesis in which changes in mitochondrial functions cooperate with RAS-induced malignant transformation.

Spontaneous and pronase-induced HER2 truncation increases the trastuzumab binding capacity of breast cancer tissues and cell lines.

A subgroup of HER2-overexpressing breast tumours co-expresses p95(HER2), a truncated HER2 receptor that retains a functional HER2 kinase domain but lacks the extracellular domain, thus impairing trastuzumab binding. We evaluated p95(HER2) expression in 99 frozen breast carcinoma samples by western blot analysis. The HER2-positive cell line BT474 treated with pervanadate or pronase was used as a positive control for p95(HER2) expression. Immunohistochemistry was performed on parallel formalin-fixed, paraffin-embedded sections of the same case series using antibodies directed against either the intra- or extra-cellular binding domain of HER2. In particular, biotinylated trastuzumab (BiotHER) was used to evaluate the binding capacity of the humanized antibody. To avoid a subjective evaluation of the score values and the percentage of immunostained cells, the slides were scanned and automatically analysed. The number of cases with HER2 overexpression (score 3+) and HER2 gene amplification was higher in the p185(HER2)-positive/p95(HER2)-positive samples than in the p185(HER2)-positive/p95(HER2)-negative group. Automated analysis confirmed a significantly higher percentage of 3+ scored cells in p95(HER2)-positive cases. Conversely, the percentage of 2+ scored cells was higher inp95(HER2)-negative cases. The status of the HER2 extracellular domain was then studied using flow cytometry on BT474 cells after pronase enzymatic digestion using trastuzumab and pertuzumab, while the presence of HER2-HER3 dimers was studied using a proximity-ligation assay. In vitro experiments showed that short-term pronase digestion of BT474 cells produced two HER2 fragments (of 95 and 150 kDa, detectable in tissue specimens as well), increased the binding affinity of trastuzumab, reduced the rate of HER2-HER3 dimers, and did not interfere with pertuzumab-binding capacity. In conclusion, the presence of p95(HER2 as detected by western blot analysis does not compromise the immunohistochemical detection of HER2. Our data suggest that a reduction of the receptor steric hindrance as induced by enzymatic shedding may facilitate the binding capacity of trastuzumab.

Diagnostic reproducibility of tumour budding in colorectal cancer: a multicentre, multinational study using virtual microscopy.

AIMS: Despite the established prognostic relevance of tumour budding in colorectal cancer, the reproducibility of the methods reported for its assessment has not yet been determined, limiting its use and reporting in routine pathology practice. METHODS AND RESULTS: A morphometric system within telepathology was devised to evaluate the reproducibility of the various methods published for the assessment of tumour budding in colorectal cancer. Five methods were selected to evaluate the diagnostic reproducibility among 10 investigators, using haematoxylin and eosin (H&E) and AE1-3 cytokeratin-immunostained, whole-slide digital scans from 50 pT1-pT4 colorectal cancers. The overall interobserver agreement was fair for all methods, and increased to moderate for pT1 cancers. The intraobserver agreement was also fair for all methods and moderate for pT1 cancers. Agreement was dependent on the participants' experience with tumour budding reporting and performance time. Cytokeratin immunohistochemistry detected a higher percentage of tumour budding-positive cases with all methods compared to H&E-stained slides, but did not influence agreement levels. CONCLUSION: An overall fair level of diagnostic agreement for tumour budding in colorectal cancer was demonstrated, which was significantly higher in early cancer and among experienced gastrointestinal pathologists. Cytokeratin immunostaining facilitated detection of budding cancer cells, but did not result in improved interobserver agreement.

The Natural History of pT1 Colorectal Cancer.

Colorectal carcinoma invading the submucosa but not the muscular layer (pT1, early invasive cancer) represents the earliest form of clinically relevant colorectal cancer in most patients. Neoplastic invasion of the submucosa, in fact, opens the way to metastasis via the lymphatic and blood vessels, and the choice between surveillance and major surgery will turn on its metastatic potential. The following histological features predict the risk of metastasis and the different clinical outcomes: grade of differentiation of carcinoma, lymphovascular invasion, state of the resection margin. Microstaging of invasive cancer, namely the width and the depth of submucosal invasion, together with tumor budding at the advancing edge allow the metastatic risk to be further stratified in minimal, low, and high. Different, although morphologically undistinguishable, tumorigenic pathways are supposed to lead to the malignant transformation of colonic mucosa and subsequently to drive the progression from early to advanced cancer: new biomarkers are needed to identify progressive and non-progressive pT1 neoplasia.

Inhibition of MEK and PI3K/mTOR suppresses tumor growth but does not cause tumor regression in patient-derived xenografts of RAS-mutant colorectal carcinomas.

PURPOSE: Gene mutations along the Ras pathway (KRAS, NRAS, BRAF, PIK3CA) occur in approximately 50% of colorectal cancers (CRC) and correlate with poor response to anti-EGF receptor (EGFR) therapies. We assessed the effects of mitogen-activated protein (MAP)/extracellular signal-regulated kinase (ERK) kinase (MEK) and phosphoinositide 3-kinase (PI3K)/mTOR inhibitors, which neutralize the major Ras effectors, in patient-derived xenografts from RAS/RAF/PIK3CA-mutant metastatic CRCs (mCRC). EXPERIMENTAL DESIGN: Forty mCRC specimens harboring KRAS, NRAS, BRAF, and/or PIK3CA mutations were implanted in nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice. Each xenograft was expanded into four treatment arms: placebo, the MEK inhibitor AZD6244, the PI3K/mTOR inhibitor, BEZ235, or AZD6244 + BEZ235. Cases initially treated with placebo crossed over to AZD6244, BEZ235, and the anti-EGFR monoclonal antibody cetuximab. RESULTS: At the 3-week evaluation time point, cotreatment of established tumors with AZD6244 + BEZ235 induced disease stabilization in the majority of cases (70%) but did not lead to overt tumor regression. Monotherapy was less effective, with BEZ235 displaying higher activity than AZD6244 (disease control rates, DCRs: AZD6244, 27.5%; BEZ235, 42.5%). Triple therapy with cetuximab provided further advantage (DCR, 88%). The extent of disease control declined at the 6-week evaluation time point (DCRs: AZD6244, 13.9%; BEZ235, 16.2%; AZD6244 + BEZ235, 34%). Cross-analysis of mice harboring xenografts from the same original tumor and treated with each of the different modalities revealed subgroups with preferential sensitivity to AZD6244 (12.5%), BEZ235 (35%), or AZD6244 + BEZ235 (42.5%); another subgroup (10%) showed equivalent response to any treatment. CONCLUSIONS: The prevalent growth-suppressive effects produced by MEK and PI3K/mTOR inhibition suggest that this strategy may retard disease progression in patients. However, data offer cautionary evidence against the occurrence of durable responses.

Standardization of whole slide image morphologic assessment with definition of a new application: Digital slide dynamic morphometry.

BACKGROUND: In histopathology, the quantitative assessment of various morphologic features is based on methods originally conceived on specific areas observed through the microscope used. Failure to reproduce the same reference field of view using a different microscope will change the score assessed. Visualization of a digital slide on a screen through a dedicated viewer allows selection of the magnification. However, the field of view is rectangular, unlike the circular field of optical microscopy. In addition, the size of the selected area is not evident, and must be calculated. MATERIALS AND METHODS: A digital slide morphometric system was conceived to reproduce the various methods published for assessing tumor budding in colorectal cancer. Eighteen international experts in colorectal cancer were invited to participate in a web-based study by assessing tumor budding with five different methods in 100 digital slides. RESULTS: The specific areas to be tested by each method were marked by colored circles. The areas were grouped in a target-like pattern and then saved as an .xml file. When a digital slide was opened, the .xml file was imported in order to perform the measurements. Since the morphometric tool is composed of layers that can be freely moved on top of the digital slide, the technique was named digital slide dynamic morphometry. Twelve investigators completed the task, the majority of them performing the multiple evaluations of each of the cases in less than 12 minutes. CONCLUSIONS: Digital slide dynamic morphometry has various potential applications and might be a useful tool for the assessment of histologic parameters originally conceived for optical microscopy that need to be quantified.

Once-only sigmoidoscopy in colorectal cancer screening: follow-up findings of the Italian Randomized Controlled Trial--SCORE.

BACKGROUND: A single flexible sigmoidoscopy at around the age of 60 years has been proposed as an effective strategy for colorectal cancer (CRC) screening. METHODS: We conducted a randomized controlled trial to evaluate the effect of flexible sigmoidoscopy screening on CRC incidence and mortality. A questionnaire to assess the eligibility and interest in screening was mailed to 236,568 men and women, aged 55-64 years, who were randomly selected from six trial centers in Italy. Of the 56,532 respondents, interested and eligible subjects were randomly assigned to the intervention group (invitation for flexible sigmoidoscopy; n = 17,148) or the control group (no further contact; n = 17,144), between June 14, 1995, and May 10, 1999. Flexible sigmoidoscopy was performed on 9911 subjects. Intention-to-treat and per-protocol analyses were performed to compare the CRC incidence and mortality rates in the intervention and control groups. Per-protocol analysis was adjusted for noncompliance. RESULTS: A total of 34,272 subjects (17,136 in each group) were included in the follow-up analysis. The median follow-up period was 10.5 years for incidence and 11.4 years for mortality; 251 subjects were diagnosed with CRC in the intervention group and 306 in the control group. Overall incidence rates in the intervention and control groups were 144.11 and 176.43, respectively, per 100,000 person-years. CRC-related death was noted in 65 subjects in the intervention group and 83 subjects in the control group. Mortality rates in the intervention and control groups were 34.66 and 44.45, respectively, per 100,000 person-years. In the intention-to-treat analysis, the rate of CRC incidence was statistically significantly reduced in the intervention group by 18% (rate ratio [RR] = 0.82, 95% confidence interval [CI] = 0.69 to 0.96), and the mortality rate was non-statistically significantly reduced by 22% (RR = 0.78; 95% CI = 0.56 to 1.08) compared with the control group. In the per-protocol analysis, both CRC incidence and mortality rates were statistically significantly reduced among the screened subjects; CRC incidence was reduced by 31% (RR = 0.69; 95% CI = 0.56 to 0.86) and mortality was reduced by 38% (RR = 0.62; 95% CI = 0.40 to 0.96) compared with the control group. CONCLUSION: A single flexible sigmoidoscopy screening between ages 55 and 64 years was associated with a substantial reduction of CRC incidence and mortality.