Follow-Up Study Confirms the Presence of Gastric Cancer DNA Methylation Hallmarks in High-Risk Precursor Lesions.

To adopt prevention strategies in gastric cancer, it is imperative to develop robust biomarkers with acceptable costs and feasibility in clinical practice to stratified populations according to risk scores. With this aim, we applied an unbiased genome-wide CpG methylation approach to a discovery cohort composed of gastric cancer (n = 24), and non-malignant precursor lesions (n = 64). Then, candidate-methylation approaches were performed in a validation cohort of precursor lesions obtained from an observational longitudinal study (n = 264), with a 12-year follow-up to identify repression or progression cases. H. pylori stratification and histology were considered to determine their influence on the methylation dynamics. As a result, we ascertained that intestinal metaplasia partially recapitulates patterns of aberrant methylation of intestinal type of gastric cancer, independently of the H. pylori status. Two epigenetically regulated genes in cancer, RPRM and ZNF793, consistently showed increased methylation in intestinal metaplasia with respect to earlier precursor lesions. In summary, our result supports the need to investigate the practical utilities of the quantification of DNA methylation in candidate genes as a marker for disease progression. In addition, the H. pylori-dependent methylation in intestinal metaplasia suggests that pharmacological treatments aimed at H. pylori eradication in the late stages of precursor lesions do not prevent epigenome reprogramming toward a cancer signature.

Helicobacter pylori pathogenicity and primary antimicrobial resistance in Northern Spain.

BACKGROUND: Helicobacter pylori infection is associated with chronic gastritis, ulcers and gastric cancer. Antimicrobial resistance has increased worldwide affecting the efficacy of current treatments. Most guidelines recommend implementation of regional surveillance of primary antibiotic resistance of H pylori. Only a fraction of individuals infected with H pylori develop gastric diseases which are related to virulence factors of the bacteria. The aims of the study were to determine the primary antimicrobial resistance rates of H pylori and to know the virulence factors prevalence of strains circulating in Southern Europe. MATERIALS AND METHODS: Susceptibility testing by Etest to clarithromycin, levofloxacin, metronidazole, amoxicillin and tetracycline was performed in 102 isolates (99 naïve patients). The prevalence of virulence factors (cagA, vacA, oipA, babA and dupA) was evaluated in 102 H pylori isolates from patients with mild-disease symptoms and in 22 isolates from patients with severe-disease symptoms. RESULTS: Primary resistance rates were 12.1% to clarithromycin, 13.1% to levofloxacin, 24.2% to metronidazole and 0% to amoxicillin and tetracycline. Combined resistance to clarithromycin and levofloxacin was 3% and to clarithromycin and metronidazole 4%. Prevalence of virulence factors in the mild- and severe-disease group was 35.3% and 81.8% for cagA, 20.6% and 54.5% for cagA/vacAs1m1, 94.1% and 95.4% for babA2, 78.4% and 100% for oipA and 30.4% and 18.2% for dupA. CONCLUSIONS: Primary antimicrobial resistance rates were under 15% for clarithromycin and levofloxacin. The prevalence of H pylori carrying the virulent genotype cagA/vacAs1m1 was higher than 20% in the mild-disease and 54% in the severe-disease symptom group.

Genetic variation analysis in a follow-up study of gastric cancer precursor lesions confirms the association of MUC2 variants with the evolution of the lesions and identifies a significant association with NFKB1 and CD14.

Gastric carcinogenesis proceeds through a series of gastric cancer precursor lesions (GCPLs) leading to gastric cancer (GC) development. Although Helicobacter pylori infection initiates this process, genetic factors also play a role. We previously reported that genetic variability in MUC2 is associated with the evolution of GCPLs. In order to replicate previous results in an independent sample series and to explore whether genetic variability in other candidate genes plays a role in the evolution of GCPL, genomic DNA from 559 patients with GCPLs, recruited from 9 Spanish hospitals and followed for a mean of 12 years, was genotyped for 141 SNPs in 29 genes. After follow-up, 45.5% of the lesions remained stable, 37% regressed and 17.5% progressed to a more severe lesion. Genetic association with the evolution of the lesions (progression or regression) was analyzed by multinomial and binomial logistic regression. After correction for multiple comparisons, the results obtained confirmed the inverse association between MUC2 variants and the regression of the lesions. A significant association was also observed between NFKB1 and CD14 variants and the evolution of the lesions; interestingly, this association was with both progression and regression in the same direction, which could reflect the dual role of inflammation in cancer. Stratified analyses according to H. pylori virulence factors indicated some significant and differential effects but none of them passed the FDR test. These results confirm that genetic variability in MUC2, NFKB1 and CD14 may have a role in the evolution of the GCPLs along time and in gastric carcinogenesis.

Antimicrobial susceptibility testing before first-line treatment for Helicobacter pylori infection in patients with dual or triple antibiotic resistance.

AIM: To evaluate the efficacy of antimicrobial susceptibility-guided therapy before first-line treatment for infection in patients with dual or triple antibiotic resistance. METHODS: A total of 1034 patients infected by Helicobacter pylori (H. pylori) during 2013-2014 were tested for antimicrobial susceptibility. 157 of 1034 (15%) patients showed resistance to two (127/1034; 12%) and to three (30/1034; 3%) antibiotics. Sixty-eight patients with dual H. pylori-resistance (clarithromycin, metronidazole or levofloxacin) were treated for 10 d with triple therapies: OAL (omeprazole 20 mg b.i.d., amoxicillin 1 g b.i.d., and levofloxacin 500 mg b.i.d.) 43 cases, OAM (omeprazole 20 mg b.i.d., amoxicillin 1 g b.i.d., and metronidazole 500 mg b.i.d.) 12 cases and OAC (omeprazole 20 mg b.id., amoxicillin 1 g b.i.d., and clarithromycin 500 mg b.i.d.) 13 cases based on the antimicrobial susceptibility testing. Twelve patients showed triple H. pylori-resistance (clarithromycin, metronidazole and levofloxacin) and received for 10 d triple therapy with OAR (omeprazole 20 mg b.id., amoxicillin 1 g b.i.d., and rifabutin 150 mg b.i.d.). Eradication was confirmed by 13C-urea breath test. Adverse effects and compliance were assessed by a questionnaire. RESULTS: Intention-to-treat eradication rates were: OAL (97.6%), OAM (91.6%), OAC (92.3%) and OAR (58.3%). Cure rate was significantly higher in naïve patients treated with OAR-10 compared to patients who had two or three previous treatment failures (83% vs 33%). Adverse events rates for OAL, OAM, OAC and OAR were 22%, 25%, 23% and 17%, respectively, all of them mild-moderate. CONCLUSION: Antimicrobial susceptibility-guided triple therapies during 10 d for first-line treatment leads to an eradication rate superior to 90% in patients with dual antibiotic H. pylori resistance.

Effect of pravastatin on the survival of patients with advanced gastric cancer.

OBJECTIVES: A fluoropyrimidine plus cisplatin combined with surgery is standard first-line treatment for advanced gastric cancer. We evaluated the effect of pravastatin on overall survival in patients with advanced gastric cancer in a prospective cohort study. METHODS: At the time of surgery, we assigned 60 patients with advanced gastric cancer (stage III or IV) to receive standard first-line treatment (control group) or standard first-line treatment plus pravastatin at a dose of 40 mg once daily (pravastatin group). The minimum follow-up period was 4 years and the maximum of 6 years. RESULTS: The mean of age was 66 years and the TNM stage was III and IV in 65% and 35% of patients, respectively. There was no significant difference between the two groups (control vs pravastatin) in median overall survival (15 vs 14 months; P = 0.8). Predictors of survival were the stage (hazard ratio of death stage IV (III stage as reference): 4.4; 95% CI: 2-9.7; p < 0.05) and older age (hazard ratio of death ≥ 65 years (< 65 years as reference): 2.8; 95% CI: 1.3-6; p < 0.05). CONCLUSIONS: Pravastatin did not improve outcome in patients with advanced gastric cancer.

Colorectal cancer in a second round after a negative faecal immunochemical test.

OBJECTIVE: The faecal immunochemical test is one of the tests recommended by scientific societies for colorectal cancer (CRC) screening in average-risk populations. Our aim was to evaluate the characteristics of CRC detected in a second round of screening after negative results in a first round. METHODS: We studied patients in whom CRC was detected in a screening programme. This programme included asymptomatic individuals between 50 and 69 years old and offered tests every 2 years. A total of 363,792 individuals were invited to participate in the first round of faecal immunochemical test screening and 100,135 individuals in the second round after a first negative result. The screening strategy consisted of faecal testing of a single sample using an automated semiquantitative kit, with a cut-off of 20 µg haemoglobin (Hb)/g faeces. RESULTS: The rate of positive results was 6.9% (16,467/238,647) in the first round and 4.8% (3359/69,193) in the second round (P < 0.0005). Overall, 860 (0.36%) cases of CRC were detected in the first round and 100 (0.14%) in the second round (P < 0.005). The location of the cancer was proximal in 12.5 and 24% of cases detected in the first and second rounds, respectively (P = 0.008). Hb concentrations were higher in the first round (211 vs. 109 µg Hb/g faeces in the second round; P = 0.002). Multivariate analysis confirmed that, in the second round, CRC diagnosed was more often proximal (hazard ratio vs. first round, 2.4; 95% confidence interval, 1.3-4.4; P = 0.003) and the concentration of Hb/g faeces was lower (hazard ratio vs. first round, 2.1; 95% confidence interval, 1.3-3.5; P = 0.003). CONCLUSION: The CRC detection rate is lower in the second round of screening. Further, in the second round, CRC detected is more often in a proximal location and Hb concentrations are lower.

Effect of aspirin and antiplatelet drugs on the outcome of the fecal immunochemical test.

OBJECTIVE: To evaluate the effect of aspirin and nonaspirin antiplatelet agents (NAAAs) on the performance of the fecal immunochemical test (FIT). PARTICIPANTS AND METHODS: We performed a post hoc analysis of results from a clinical trial that involved 28,696 asymptomatic average-risk men and women aged 50 to 69 years invited to participate in a colorectal cancer screening program with FIT between November 1, 2008, and June 31, 2011. RESULTS: The test was returned by 6390 individuals (22.3%), of whom 5821 (91.1%) reported not using antiplatelet drugs (nonusers group) and 569 (8.9%) reported using these drugs at the time of testing (users group). The FIT result was positive in 48 of 569 users (8.4%) and 365 of 5821 nonusers (6.3%) (P=.05). A positive FIT result was found in 7.3% (28/384) of aspirin users, 7.1% (10/140) of NAAA users, and 22.2% (10/45) of those undergoing dual antiplatelet therapy (DAPT) (aspirin plus an NAAA). The DAPT subgroup had a significantly higher positive FIT rate than the nonuser group (odds ratio, 3.5; 95% CI, 1.7-7.3; P<.05). The positive predictive value (PPV) for advanced neoplasia (AN) in nonusers was 50.4% vs 50.0% in users (P = .40). The PPV for AN was 57.0% in aspirin users, 30.0% in NAAA users, and 50.0% in DAPT users, without statistically significant differences between the user and nonuser groups. CONCLUSION: The use of DAPT increased the rate of positive FIT results. Use of aspirin, NAAAs, or both did not modify the PPV for AN in this population-based colorectal screening program.

Risk of advanced proximal neoplasms according to distal colorectal findings: comparison of sigmoidoscopy-based strategies.

BACKGROUND: Screening for colorectal cancer with sigmoidoscopy benefits from the fact that distal findings predict the risk of advanced proximal neoplasms (APNs). This study was aimed at comparing the existing strategies of postsigmoidoscopy referral to colonoscopy in terms of accuracy and resources needed. METHODS: Asymptomatic individuals aged 50-69 years were eligible for a randomized controlled trial designed to compare colonoscopy and fecal immunochemical test. Sigmoidoscopy yield was estimated from results obtained in the colonoscopy arm according to three sets of criteria of colonoscopy referral (from those proposed in the UK Flexible Sigmoidoscopy, Screening for COlon REctum [SCORE], and Norwegian Colorectal Cancer Prevention [NORCCAP] trials). Advanced neoplasm detection rate, sensitivity, specificity, and number of individuals needed to refer for colonoscopy to detect one APN were calculated. Logistic regression analysis was performed to identify distal findings associated with APN. All statistical tests were two-sided. RESULTS: APN was found in 255 of 5059 (5.0%) individuals. Fulfillment of UK (6.2%), SCORE (12.0%), and NORCCAP (17.9%) criteria varied statistically significantly (P < .001). The NORCCAP strategy obtained the highest sensitivity for APN detection (36.9%), and the UK approach reached the highest specificity (94.6%). The number of individuals needed to refer for colonoscopy to detect one APN was 6 (95% confidence interval [CI] = 4 to 7), 8 (95% CI = 6 to 9), and 10 (95% CI = 8 to 12) when the UK, SCORE, and NORCCAP criteria were used, respectively. The logistic regression analysis identified distal adenoma ≥10 mm (odds ratio = 3.77; 95% CI = 2.52 to 5.65) as the strongest independent predictor of APN. CONCLUSIONS: Whereas the NORCCAP criteria achieved the highest sensitivity for APN detection, the UK recommendations benefited from the lowest number of individuals needed to refer for colonoscopy.

Alcohol consumption on pancreatic diseases.

Although the association between alcohol and pancreatic diseases has been recognized for a long time, the impact of alcohol consumption on pancreatitis and pancreatic cancer (PC) remains poorly defined. Nowadays there is not consensus about the epidemiology and the beverage type, dose and duration of alcohol consumption causing these diseases. The objective of this study was to review the epidemiology described in the literature for pancreatic diseases as a consequence of alcoholic behavior trying to understand the association between dose, type and frequency of alcohol consumption and risk of pancreatitis and PC. The majority of the studies conclude that high alcohol intake was associated with a higher risk of pancreatitis (around 2.5%-3% between heavy drinkers and 1.3% between non drinkers). About 70% of pancreatitis are due to chronic heavy alcohol consumption. Although this incidence rate differs between countries, it is clear that the risk of developing pancreatitis increases with increasing doses of alcohol and the average of alcohol consumption vary since 80 to 150 g/d for 10-15 years. With regard to PC, the role of alcohol consumption remains less clear, and low to moderate alcohol consumption do not appear to be associated with PC risk, and only chronic heavy drinking increase the risk compared with lightly drinkers. In a population of 10%-15% of heavy drinkers, 2%-5% of all PC cases could be attributed to alcohol consumption. However, as only a minority (less than 10% for pancreatitis and 5% for PC) of heavily drinkers develops these pancreatic diseases, there are other predisposing factors besides alcohol involved. Genetic variability and environmental exposures such as smoking and diet modify the risk and should be considered for further investigations.

Evaluation of alpha 1-antitrypsin and the levels of mRNA expression of matrix metalloproteinase 7, urokinase type plasminogen activator receptor and COX-2 for the diagnosis of colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is the second most common cause of death from cancer in both men and women in the majority of developed countries. Molecular tests of blood could potentially provide this ideal screening tool. AIM: Our objective was to assess the usefulness of serum markers and mRNA expression levels in the diagnosis of CRC. METHODS: In a prospective study, we measured mRNA expression levels of 13 markers (carbonic anhydrase, guanylyl cyclase C, plasminogen activator inhibitor, matrix metalloproteinase 7 (MMP7), urokinase-type plasminogen activator receptor (uPAR), urokinase-type plasminogen activator, survivin, tetranectin, vascular endothelial growth factor (VEGF), cytokeratin 20, thymidylate synthase, cyclooxygenase 2 (COX-2), and CD44) and three proteins in serum (alpha 1 antitrypsin, carcinoembryonic antigen (CEA) and activated C3 in 42 patients with CRC and 33 with normal colonoscopy results. RESULTS: Alpha 1-antitrypsin was the serum marker that was most useful for CRC diagnosis (1.79 ± 0.25 in the CRC group vs 1.27 ± 0.25 in the control group, P<0.0005). The area under the ROC curve for alpha 1-antitrypsin was 0.88 (0.79-0.96). The mRNA expression levels of five markers were statistically different between CRC cases and controls: those for which the ROC area was over 75% were MMP7 (0.81) and tetranectin (0.80), COX-2 (0.78), uPAR (0.78) and carbonic anhydrase (0.77). The markers which identified early stage CRC (Stages I and II) were alpha 1-antitrypsin, uPAR, COX-2 and MMP7. CONCLUSIONS: Serum alpha 1-antitrypsin and the levels of mRNA expression of MMP7, COX-2 and uPAR have good diagnostic accuracy for CRC, even in the early stages.

Spontaneous regression of pancreatic cancer: real or a misdiagnosis?

Spontaneous tumor regression has been subject of numerous studies and speculations for many years. This phenomenon is exceptional, but well reported, in some types of tumors, but not in pancreatic cancer. Pancreatic cancer has the worst five-year survival rate of any cancer. Despite numerous molecular studies and clinical approaches, using several mouse models, this cancer responds poorly to the existing chemotherapeutic agents and progress on treatment remains elusive. Although pancreatic cancer tumors seldom undergo spontaneous regression, and some authors take that with skepticism, there are some cases reported in the literature. However, the variability in the description of the reports and technical details could make this process susceptible to misdiagnosis. Distinguishing between different types of pancreatic carcinoma should be taken with caution as they have wide differences in malignant potential. Diseases such as pancreatic benign tumors, insulinomas, or autoimmune pancreatitis could be responsible for this misdiagnosis as a pancreatic cancer. Here we review different cases reported, their clinical characteristics, and possible mechanisms leading to spontaneous regression of pancreatic cancer. We also discuss the possibilities of misdiagnosis.

Adjuvant and neoadjuvant treatment in pancreatic cancer.

Pancreatic adenocarcinoma is one of the most aggressive human malignancies, ranking 4th among causes for cancer-related death in the Western world including the United States. Surgical resection offers the only chance of cure, but only 15 to 20 percent of cases are potentially resectable at presentation. Different studies demonstrate and confirm that advanced pancreatic cancer is among the most complex cancers to treat and that these tumors are relatively resistant to chemotherapy and radiotherapy. Currently there is no consensus around the world on what constitutes "standard" adjuvant therapy for pancreatic cancer. This controversy derives from several studies, each fraught with its own limitations. Standards of care also vary somewhat with regard to geography and economy, for instance chemo-radiotherapy followed by chemotherapy or vice versa is considered the optimal therapy in North America while chemotherapy alone is the current standard in Europe. Regardless of the efforts in adjuvant and neoadjuvant improved therapy, the major goal to combat pancreatic cancer is to find diagnostic markers, identifying the disease in a pre-metastatic stage and making a curative treatment accessible to more patients. In this review, authors examined the different therapy options for advanced pancreatic patients in recent years and the future directions in adjuvant and neoadjuvant treatments for these patients.

Mouse models of pancreatic cancer.

Pancreatic cancer is one of the most lethal of human malignancies ranking 4th among cancer-related death in the western world and in the United States, and potent therapeutic options are lacking. Although during the last few years there have been important advances in the understanding of the molecular events responsible for the development of pancreatic cancer, currently specific mechanisms of treatment resistance remain poorly understood and new effective systemic drugs need to be developed and probed. In vivo models to study pancreatic cancer and approach this issue remain limited and present different molecular features that must be considered in the studies depending on the purpose to fit special research themes. In the last few years, several genetically engineered mouse models of pancreatic exocrine neoplasia have been developed. These models mimic the disease as they reproduce genetic alterations implicated in the progression of pancreatic cancer. Genetic alterations such as activating mutations in KRas, or TGFb and/or inactivation of tumoral suppressors such as p53, INK4A/ARF BRCA2 and Smad4 are the most common drivers to pancreatic carcinogenesis and have been used to create transgenic mice. These mouse models have a spectrum of pathologic changes, from pancreatic intraepithelial neoplasia to lesions that progress histologically culminating in fully invasive and metastatic disease and represent the most useful preclinical model system. These models can characterize the cellular and molecular pathology of pancreatic neoplasia and cancer and constitute the best tool to investigate new therapeutic approaches, chemopreventive and/or anticancer treatments. Here, we review and update the current mouse models that reproduce different stages of human pancreatic ductal adenocarcinoma and will have clinical relevance in future pancreatic cancer developments.

Susceptibility genetic variants associated with early-onset colorectal cancer.

Colorectal cancer (CRC) is the second most common cancer in Western countries. Hereditary forms only correspond to 5% of CRC burden. Recently, genome-wide association studies have identified common low-penetrant CRC genetic susceptibility loci. Early-onset CRC (CRC<50 years old) is especially suggestive of hereditary predisposition although 85-90% of heritability still remains unidentified. CRC<50 patients (n = 191) were compared with a late-onset CRC group (CRC>65 years old) (n = 1264). CRC susceptibility variants at 8q23.3 (rs16892766), 8q24.21 (rs6983267), 10p14 (rs10795668), 11q23.1 (rs3802842), 15q13.3 (rs4779584), 18q21 (rs4939827), 14q22.2 (rs4444235), 16q22.1 (rs9929218), 19q13.1 (rs10411210) and 20p12.3 (rs961253) were genotyped in all DNA samples. A genotype-phenotype correlation with clinical and pathological characteristics in both groups was performed. Risk allele carriers for rs3802842 [Odds ratio (OR) = 1.5, 95% confidence interval (CI) 1.1-2.05, P = 0.0096, dominant model) and rs4779584 (OR = 1.39, 95% CI 1.02-1.9, P = 0.0396, dominant model) were more frequent in the CRC<50 group, whereas homozygotes for rs10795668 risk allele were also more frequent in the early-onset CRC (P = 0.02, codominant model). Regarding early-onset cases, 14q22 (rs4444235), 11q23 (rs3802842) and 20p12 (rs961253) variants were more associated with family history of CRC or tumors of the Lynch syndrome spectrum excluding CRC. In our entire cohort, sum of risk alleles was significantly higher in patients with a CRC family history (OR = 1.40, 95% CI 1.06-1.85, P = 0.01). In conclusion, variants at 10p14 (rs10795668), 11q23.1 (rs3802842) and 15q13.3 (rs4779584) may have a predominant role in predisposition to early-onset CRC. Association of CRC susceptibility variants with some patient's familiar and personal features could be relevant for screening and surveillance strategies in this high-risk group and it should be explored in further studies.

Diagnosis of Whipple's disease using molecular biology techniques.

The diagnosis of Whipple's disease (WD) is based on the existence of clinical signs and symptoms compatible with the disease and in the presence of PAS-positive diastase-resistant granules in the macrophages of the small intestine. If there is suspicion of the disease but no histological findings or only isolated extraintestinal manifestations, species-specific PCR using different sequences of the T. whippleii genome from different tissue types and biological fluids is recommended.This study reports two cases: the first patient had diarrhea and the disease was suspected after an endoscopic examination of the ileum, while the second patient had multi-systemic manifestations,particularly abdominal, thoracic, and peripheral lymphadenopathies. In both cases, the diagnosis was confirmed using molecular biology techniques to samples from the small intestine or from a retroperineal lymph node, respectively.

Clinical patterns and outcomes of ischaemic colitis: results of the Working Group for the Study of Ischaemic Colitis in Spain (CIE study).

BACKGROUND: There is a lack of prospective studies evaluating the natural history of colonic ischaemia (CI). We performed such a study to evaluate the clinical presentation, outcome, and mortality as well as clinical variables associated with poor prognosis. METHODS: An open, prospective, and multicentre study was conducted in 24 Spanish hospitals serving a population of 3.5 million people. The study included only patients who met criteria for definitive or probable CI. A website (www.colitisisquemica.org) provided logistical support. RESULTS: A total of 364 patients met criteria for inclusion. CI was suspected clinically in only 24.2% of cases. The distribution of clinical patterns was as follows: reversible colopathy (26.1%), transient colitis (43.7%), gangrenous colitis (9.9%), fulminant pancolitis (2.5%), and chronic segmental colitis (17.9%). A total of 47 patients (12.9%) had an unfavorable outcome as defined by mortality and/or the need for surgery. Multivariate analysis identified the following signs as independent risk factors for an unfavorable outcome: abdominal pain without rectal bleeding [odds ratio (OR) 3.9; 95% confidence interval (CI) = 1.6-9.3], non-bloody diarrhoea (OR 10; 95% CI = 3.7-27.4), and peritoneal signs (OR 7.3; 95% CI = 2.7-19.6). Unfavorable outcomes also were more frequent in isolated right colon ischaemia (IRCI) compared with non-IRCI (40.9 vs. 10.3%, respectively; p < 0.0001). The overall mortality rate was 7.7%. CONCLUSIONS: The clinical presentation of CI is very heterogeneous, perhaps explaining why clinical suspicion of this disease is so low. The presence of IRCI, and occurrence of peritoneal signs or onset of CI as severe abdominal pain without bleeding, should alert the physician to a potentially unfavorable course.

Malignant colorectal polyps.

Nowadays, the number of cases in which malignant colorectal polyps are removed is increasing due to colorectal cancer screening programmes. Cancerous polyps are classified into non-invasive high grade neoplasia (NHGN), when the cancer has not reached the muscularis mucosa, and malignant polyps, classed as T1, when they have invaded the submucosa. NHGN is considered cured with polypectomy, while the prognosis for malignant polyps depends on various morphological and histological factors. The prognostic factors include, sessile or pedunculated morphology of the polyp, whether partial or en bloc resection is carried out, the degree of differentiation of the carcinoma, vascular or lymphatic involvement, and whether the polypectomy resection margin is tumor free. A malignant polyp at T1 is considered cured with polypectomy if it is a pedunculated polyp (Ip of the Paris classification), it has been completely resected, it is not poorly differentiated, the resection edge is not affected by the tumor and there is no vascular or lymphatic involvement. The sessile malignant polyp (Is of the Paris classification) at T1 is considered not cured with polypectomy. Only in some cases (e.g. older people with high surgical risk) local excision (polypectomy or endoscopic submucosal dissection or conventional endoscopic mucosal resection) is considered the definitive treatment.