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Featured researches published by Juan Clofent.


Gut | 2006

Mismatch repair status in the prediction of benefit from adjuvant fluorouracil chemotherapy in colorectal cancer

Rodrigo Jover; Pedro Zapater; Antoni Castells; Xavier Llor; Montserrat Andreu; Joaquín Cubiella; Virginia Piñol; Rosa M. Xicola; Luis Bujanda; Josep M. Reñé; Juan Clofent; Xavier Bessa; Juan Diego Morillas; David Nicolás-Pérez; Artemio Payá; Cristina Alenda

Aim: Some retrospective studies have shown a lack of benefit of 5-fluorouracil (5-FU) adjuvant chemotherapy in patients with mismatch repair (MMR) deficient colorectal cancer. Our aim was to assess if this molecular marker can predict benefit from 5-FU adjuvant chemotherapy. A second objective was to determine if MMR status influences short term survival. Methods: We included 754 patients with a median follow up of 728.5 days (range 1–1097). A total of 260 patients with stage II or III tumours received 5-FU adjuvant chemotherapy, according to standard clinical criteria and irrespective of their MMR status. A tumour was considered MMR deficient when either BAT-26 showed instability or there was loss of MLH1 or MSH2 protein expression. Results: At the end of the follow up period, 206 patients died and 120 presented with tumour recurrence. Sixty six (8.8%) patients had MMR deficient tumours. There were no significant differences in overall survival (MMR competent 72.1%; MMR deficient 78.8%; p = 0.3) or disease free survival (MMR competent 61.3%; MMR deficient 72.3%; p = 0.08). In patients with stage II and III tumours, benefit from 5-FU adjuvant chemotherapy was restricted to patients with MMR competent tumours (overall survival: chemotherapy 87.1%; non-chemotherapy 73.5%; log rank, p = 0.00001). Patients with MMR deficient tumours did not benefit from adjuvant chemotherapy (overall survival: chemotherapy 89.5%; non-chemotherapy 82.4%; log rank, p = 0.4). Conclusions: Benefit from 5-FU adjuvant chemotherapy depends on the MMR status of tumours in patients with colorectal cancer. 5-FU adjuvant chemotherapy improves survival in patients with MMR competent tumours but this benefit from chemotherapy cannot be extended to patients with MMR deficient tumours.


Gastroenterology | 2011

5-Fluorouracil Adjuvant Chemotherapy Does Not Increase Survival in Patients With CpG Island Methylator Phenotype Colorectal Cancer

Rodrigo Jover; Thuy–Phuong Nguyen; Lucía Pérez–Carbonell; Pedro Zapater; Artemio Payá; Cristina Alenda; Estefanía Rojas; Joaquín Cubiella; Francesc Balaguer; Juan Diego Morillas; Juan Clofent; Luis Bujanda; Josep M. Reñé; Xavier Bessa; Rosa M. Xicola; David Nicolás–Pérez; Antoni Castells; Montserrat Andreu; Xavier Llor; C. Richard Boland; Ajay Goel

BACKGROUND & AIMS 5-Fluorouracil (5-FU)-based adjuvant chemotherapy does not increase survival times of patients with colorectal tumors with microsatellite instability. We determined the response of patients with colorectal tumors with the CpG island methylator phenotype (CIMP) to 5-FU-based therapy. METHODS We analyzed a population-based cohort of 302 patients with colorectal cancer (CRC) for a median follow-up time of 50.7 months. CIMP status was determined by analysis of the CACNAG1, SOCS1, RUNX3, NEUROG1, and MLH1 promoters; tumors were considered to be CIMP positive if at least 3 promoters were methylated. RESULTS Tumors from 29.5% of patients (89/302) were CIMP positive; CIMP status did not influence disease-free survival (DFS; log-rank = 0.3). Of tumors of TNM stages II-III (n = 196), 32.7% were CIMP positive. Among patients with stages II-III CRC who did not receive adjuvant 5-FU chemotherapy, those with CIMP-positive tumors had longest times of DFS (log-rank = 0.04); In patients who received chemotherapy, those with CIMP-positive tumors had shorter times of DFS (log-rank = 0.02). In patients with CIMP-negative tumors, adjuvant 5-FU chemotherapy significantly increased time of DFS (log-rank = 0.00001). However, in patients with CIMP-positive tumors, adjuvant 5-FU chemotherapy did not affect time of DFS (log-rank = 0.7). Multivariate analysis showed a significant, independent interaction between 5-FU treatment and CIMP status (hazard ratio [HR], 0.6; 95% confidence interval [CI], 0.5-0.8). Among patients with CIMP-positive tumors, adjuvant chemotherapy was not an independent predictor of outcome (HR, 0.8; 95% CI, 0.3-2.0). In patients who did not receive adjuvant 5-FU chemotherapy, CIMP status was the only independent predictor of survival (HR, 2.0; 95% CI, 1.1-3.8). CONCLUSIONS Patients with CIMP-positive colorectal tumors do not benefit from 5-FU-based adjuvant chemotherapy.


European Journal of Cancer | 2009

The efficacy of adjuvant chemotherapy with 5-fluorouracil in colorectal cancer depends on the mismatch repair status

Rodrigo Jover; Pedro Zapater; Antoni Castells; Xavier Llor; Montserrat Andreu; Joaquín Cubiella; Francesc Balaguer; Laura Sempere; Rosa M. Xicola; Luis Bujanda; Josep M. Reñé; Juan Clofent; Xavier Bessa; Juan Diego Morillas; David Nicolás-Pérez; Elisenda Pons; Artemio Payá; Cristina Alenda

AIMS The aim of this study is to evaluate if mismatch repair (MMR) defective colorectal cancer has a different response to adjuvant 5-fluorouracil (5-FU) chemotherapy in a cohort of patients prospectively followed during 5 years. METHODS The cohort included 754 surgically treated patients with colorectal cancer. MMR status was diagnosed by MLH1 and MSH2 immunohistochemistry and microsatellite instability analysis. Median follow-up was 49.2 months (range 1-73). At inclusion, 505 patients were diagnosed as TNM II or III stage, analysis of the efficacy of adjuvant chemotherapy was made on this population. Adjuvant chemotherapy was applied to 248 patients (98.2% 5-FU based). RESULTS MMR deficiency was found in 76 patients (10.1%). No differences were found in overall survival (log-rank p=0.3) or disease-free survival (log-rank p=0.3) regarding MMR status. Adjuvant chemotherapy improves survival in patients in the II or III stage, but this improvement is only evident in patients with MMR-competent tumours (log-rank p=0.00001). Survival of patients with MMR-defective tumours does not improve with adjuvant chemotherapy (log-rank p=0.7). A multivariate analysis showed an independent effect of the interaction between MMR status and adjuvant chemotherapy (Hazard ratio 2.04; 95% confidence interval: 1.42-2.93). CONCLUSION In a cohort of colorectal cancer patients, those with MMR-deficient tumours seem not to benefit from 5-FU-based chemotherapy.


Gastroenterology | 2013

Risk of Cancer in Cases of Suspected Lynch Syndrome Without Germline Mutation

María Rodríguez Soler; Lucía Pérez–Carbonell; Carla Guarinos; Pedro Zapater; Adela Castillejo; Víctor Manuel Barberá; Miriam Juárez; Xavier Bessa; Rosa M. Xicola; Juan Clofent; Luis Bujanda; Francesc Balaguer; Josep–Maria Reñé; Luisa de Castro; José–Carlos Marín–Gabriel; Angel Lanas; Joaquín Cubiella; David Nicolás–Pérez; Alejandro Brea–Fernández; Sergi Castellví–Bel; Cristina Alenda; Clara Ruiz–Ponte; Angel Carracedo; Antoni Castells; Montserrat Andreu; Xavier Llor; José L. Soto; Artemio Payá; Rodrigo Jover

BACKGROUND & AIMS Colorectal cancers (CRCs) with microsatellite instability (MSI) and a mismatch repair (MMR) immunohistochemical deficit without hypermethylation of the MLH1 promoter are likely to be caused by Lynch syndrome. Some patients with these cancers have not been found to have pathogenic germline mutations and are considered to have Lynch-like syndrome (LLS). The aim of this study was to determine the risk of cancer in families of patients with LLS. METHODS We studied a population-based cohort of 1705 consecutive patients, performing MSI tests and immunohistochemical analyses of MMR proteins. Patients were diagnosed with Lynch syndrome when they were found to have pathogenic germline mutations. Patients with MSI and loss of MSH2 and/or MSH6 expression, isolated loss of PMS2 or loss of MLH1 without MLH1 promoter hypermethylation, and no pathogenic mutation were considered to have LLS. The clinical characteristics of patients and the age- and sex-adjusted standardized incidence ratios (SIRs) of cancer in families were compared between groups. RESULTS The incidence of CRC was significantly lower in families of patients with LLS than in families with confirmed cases of Lynch syndrome (SIR for Lynch syndrome, 6.04; 95% confidence interval [CI], 3.58-9.54; SIR for LLS, 2.12; 95% CI, 1.16-3.56; P < .001). However, the incidence of CRC was higher in families of patients with LLS than in families with sporadic CRC (SIR for sporadic CRC, 0.48; 95% CI, 0.27-0.79; P < .001). CONCLUSIONS The risk of cancer in families with LLS is lower that of families with Lynch syndrome but higher than that of families with sporadic CRC. These results confirm the need for special screening and surveillance strategies for these patients and their relatives.


Gut | 2007

Low adherence to colonoscopy in the screening of first- degree relatives of patients with colorectal cancer

Luis Bujanda; Cristina Sarasqueta; Leire Zubiaurre; Angel Cosme; Carmen Muñoz; Araceli Sánchez; Cristina Martín; Llúcia Titó; Virginia Piñol; Antoni Castells; Xavier Llor; Rosa M. Xicola; Elisenda Pons; Juan Clofent; Maria Dolores Luque de Castro; Jaime Cuquerella; Enrique Medina; Ana Gutiérrez; Juan Arenas; Rodrigo Jover

Background: Colonoscopy is one of the methods of choice for screening relatives of patients with colorectal cancer. Objective: To evaluate the rate of adherence to colonoscopy in first-degree relatives of patients with colorectal cancer and describe the lesions found. Methods: A prospective, cross-sectional, multicentre, nationwide study was conducted. The study population was composed of first-degree relatives of patients with colorectal cancer selected randomly from the EPICOLON study. Seventy-four index patients were included. These had 342 living first-degree relatives (parents, siblings and children), of whom 281 were interviewed. Results: The adherence rate was 38% (107/281). Adherence was greater in families with a higher degree of familial aggregation for colorectal cancer (88.9% for Amsterdam vs 33.3% for Bethesda and sporadic cancer; p<0.05), an index patient aged under 65 years (60% for patients <65 years vs 32.9% for patients ⩾65 years; p<0.05) and an index patient who was female (46.2% for women vs 31% for men; p = 0.28). Adherence was also greater in relatives under 65 years (54% in patients <65 years vs 18% in patients ⩾65 years; p = 0.05), in female relatives (49% in female relatives vs 27.3% in male relatives; p<0.05) and in siblings and children (40% in siblings and children vs 13% in parents; p<0.05). Lesions were found in 26% (28/107) of the study population. Nine (8.4%) individuals had a total of 18 advanced lesions. Conclusions: These results indicate that adherence to colonoscopy in our population of first-degree relatives was low. The adherence was more frequently associated with a higher degree of familial aggregation, a relative age of under 65 years, a sibling or offspring relationship, and female sex.


Digestion | 2007

Dysplasia and Cancer in Inflammatory Bowel Disease 10 Years after Diagnosis: Results of a Population-Based European Collaborative Follow-Up Study

K.H. Katsanos; Severine Vermeire; D.K. Christodoulou; Lene Riis; Frank Wolters; S. Odes; João Freitas; Ole Høie; Marina Beltrami; Giovanni Fornaciari; Juan Clofent; Paolo Bodini; Morten H. Vatn; Paula Borralho Nunes; Bjørn Moum; P. Munkholm; Charles Limonard; R.W. Stockbrügger; P. Rutgeerts; E.V. Tsianos

Objective: To determine dysplasia and cancer in the 1991–2004 European Collaborative Inflammatory Bowel Disease (EC-IBD) Study Group cohort. Patients and Methods: A patient questionnaire and a physician per patient form were completed for each of the 1,141 inflammatory bowel disease patients (776 ulcerative colitis/365 Crohn’s disease) from 9 centers (7 countries) derived from the EC-IBD cohort. Rates of detection of intestinal cancer and dysplasia as well as extra-intestinal neoplasms were computed. Results: Patient follow-up time was 10.3 ± 0.8 (range 9.4–11) years. The mean age of the whole group of IBD patients was 37.8 ± 11.3 (range 16–76) years. Thirty-eight patients (3.3%; 26 with ulcerative colitis/12 with Crohn’s disease, 21 males/17 females, aged 61.3 ± 13.4, range 33–77 years), were diagnosed with 42 cancers. Cancers occurred 5.4 ± 3.3 (range 0–11) years after inflammatory bowel disease diagnosis. Colorectal cancer was diagnosed in 8 (1 Crohn’s disease and 7 ulcerative colitis patients – 0.3 and 0.9% of the Crohn’s disease and ulcerative colitis cohort, respectively) of 38 patients and 30 cancers were extra-intestinal. Four of 38 patients (10.5%) were diagnosed as having 2 cancers and they were younger compared to patients with one cancer (p = 0.0008). There was a trend for a higher prevalence of intestinal cancer in the northern centers (0.9%) compared to southern centers (0.3%, p = NS). Southern centers had more cases of extra-intestinal cancer compared to northern centers (2 vs. 3.8%, p = 0.08). Ten patients (0.9%; 8 with ulcerative colitis/2 with Crohn’s disease, 8 males, aged 62.3 ± 14.1 years) had colorectal dysplasia. Conclusions: In the first decade of the EC-IBD Study Group cohort follow-up study, the prevalence of cancer was as expected with most patients having a single neoplasm and an extra-intestinal neoplasm. In northern centers there was a trend for more intestinal cancers, while in southern centers there was a trend for more extra-intestinal cancers compared to northern centers.


Gastroenterology | 2010

Susceptibility Genetic Variants Associated With Colorectal Cancer Risk Correlate With Cancer Phenotype

Anna Abulí; Xavier Bessa; Juan R. González; Clara Ruiz–Ponte; Alejandro Cáceres; Jenifer Muñoz; Victoria Gonzalo; Francesc Balaguer; Ceres Fernández–Rozadilla; Dolors González; Luisa de Castro; Juan Clofent; Luis Bujanda; Joaquín Cubiella; Josep M. Reñé; Juan Diego Morillas; Angel Lanas; Joaquim Rigau; Ana Ma García; Mercedes Latorre; Joan Saló; Fernando Fernández Bañares; Lidia Argüello; E. Peña; Angels Vilella; Sabino Riestra; Ramiro Carreño; Artemio Payá; Cristina Alenda; Rosa M. Xicola

BACKGROUND & AIMS Ten common low-penetrant genetic variants have been consistently associated with colorectal cancer (CRC) risk; little is known about the correlation between these variants and CRC phenotype. Characterization of such a correlation would improve CRC management and prevention programs. We assessed the association between these genetic variants and CRC phenotype in patients and modeled pairwise combinations to detect epistasis. METHODS The validation population corresponded to a prospective, multicenter, population-based cohort (EPICOLON I) of 1096 patients with newly diagnosed CRC. The replication set was an independent, prospective, multicenter Spanish cohort (EPICOLON II) of 895 patients with newly diagnosed CRC. For individual single nucleotide polymorphism (SNP) association analyses, a multivariate method using logistic regression was applied in EPICOLON I and subsequently prospectively validated in EPICOLON II. Interactions between SNPs were assessed using the likelihood ratio test. RESULTS Validated results confirmed that the C allele on 8q23.3 (rs16892766) was significantly associated with advanced-stage tumors (odds ratio [OR], 1.48; 95% confidence interval [CI], 1.15-1.90; P value = 4.9 x 10(-3)). The G allele on 8q24.21 (rs6983267) was more common in patients with a familial history of CRC (OR, 2.02; 95% CI, 1.35-3.03; P value = 3.9 x 10(-4)). The combination of rs6983267 on 8q24.21 and rs9929218 on 16q22.2 was associated with a history of colorectal adenoma (carriers of GG and AA, respectively; OR, 2.28; 95% CI, 1.32-3.93; P = 5.0 x 10(-4)). CONCLUSIONS CRC susceptibility variants at 8q23.3, 8q24.21, and 16q22.2 appear to be associated with cancer phenotype. These findings might be used to develop screening and surveillance strategies.


Journal of Crohns & Colitis | 2011

Cancer in inflammatory bowel disease 15 years after diagnosis in a population-based European Collaborative follow-up study ☆

Konstantinos Katsanos; Athina Tatsioni; Natalia Pedersen; Mary Shuhaibar; Vicent Hernandez Ramirez; Patrizia Politi; Evelien Rombrechts; Marieke Pierik; Juan Clofent; Marina Beltrami; Paolo Bodini; João Freitas; Ioannis A. Mouzas; Giovanni Fornaciari; Bjørn Moum; Peter L. Lakatos; Severine Vermeire; Ebbe Langholz; Selwyn Odes; Colm O’Morain; R.W. Stockbrügger; Pia Munkholm; Epameinondas V. Tsianos

AIM OF THE STUDY To determine the occurrence of intestinal and extraintestinal cancers in the 1993-2009 prospective European Collaborative Inflammatory Bowel Disease (EC-IBD) Study Group cohort. PATIENTS-METHODS A physician per patient form was completed for 681 inflammatory bowel disease patients (445UC/236CD) from 9 centers (7 countries) derived from the original EC-IBD cohort. For the 15-year follow up period, rates of detection of intestinal and extraintestinal cancers were computed. RESULTS Patient follow-up time was fifteen years. In total 62/681 patients (9.1%) [41 with ulcerative colitis/21 with Crohns disease, 36 males/26 females] were diagnosed with sixty-six cancers (four patients with double cancers). Colorectal cancer was diagnosed in 9/681 patients [1.3%] (1 Crohns disease and 8 ulcerative colitis). The remaining 53 cancers were extraintestinal. There was a higher prevalence of intestinal cancer in the Northern centers compared to Southern centers [p=NS]. Southern centers had more cases of extraintestinal cancer compared to Northern centers [p=NS]. The frequency of all observed types of cancers in Northern and in Southern centers did not differ compared to the expected one in the background population. CONCLUSIONS In the fifteen-year follow up of the EC-IBD Study Group cohort the prevalence of cancer was 9.1% with most patients having a single neoplasm and an extraintestinal neoplasm. In Northern centers there were more intestinal cancers while in Southern centers there were more extraintestinal cancers compared to Northern centers. In this IBD cohort the frequency of observed cancers was not different from that expected in the background population.


Inflammatory Bowel Diseases | 2007

Role of ASCA and the NOD2/CARD15 mutation Gly908Arg in predicting increased surgical costs in Crohn's disease patients: A project of the European Collaborative Study Group on Inflammatory Bowel Disease

S. Odes; Michael Friger; Hillel Vardi; Greet Claessens; Xavier Bossuyt; Lene Riis; P. Munkholm; Frank Wolters; Hagit Yona; Ole Høie; Marina Beltrami; Epameinondas V. Tsianos; K.H. Katsanos; Ioannis A. Mouzas; Juan Clofent; Estela Monteiro; Andrea Messori; Patrizia Politi; Colm O'Morain; Charles Limonard; Maurice G. Russel; Morten H. Vatn; Bjørn Moum; R.W. Stockbrügger; Severine Vermeire

Background: NOD2/CARD15, the first identified susceptibility gene in Crohns disease (CD), is associated with ileal stenosis and increased frequency of surgery. Anti‐Saccharomyces cerevisiae antibody (ASCA), a serological marker for CD, is associated with ileal location and a high likelihood for surgery. We hypothesized that the presence of ASCA and NOD2/CARD15 mutations could predict increased health care cost in CD. Methods: CD patients in a prospectively designed community‐based multinational European and Israeli cohort (n = 228) followed for mean 8.3 (SD 2.6) years had blood drawn for measurement of ASCA (IgG, IgA), Arg702Trp, Gly908Arg, and Leu1007fsinsC. Days spent in the hospital and the costs of medical and surgical hospitalizations and medications were calculated. Results: The median duration of surgical hospitalizations was longer in Gly908Arg‐positive than ‐negative patients, 3.5 and 1.5 days/patient‐year (P < 0.01), and in ASCA‐positive than ‐negative patients, 1.1 and 0 days/patient‐year (P < 0.001). Median surgical hospitalization cost was 1,580 &U20AC;/patient‐year in Gly908Arg‐positive versus 0 &U20AC;/patient‐year in ‐negative patients (P < 0.01), and 663 &U20AC;/patient‐year in ASCA‐positive versus 0 &U20AC;/patient‐year in ‐negative patients (P < 0.001). Differences in cost of medications between groups were not significant. The effect of Gly908Arg was expressed in countries with higher Gly908Arg carriage rates. ASCA raised surgical costs independently of the age at diagnosis of disease. Arg702Trp and Leu1007fsinsC did not affect the cost of health care. Conclusions: Since CD patients positive for Gly908Arg and ASCA demonstrated higher health care costs, it is possible that measurement of Gly908Arg and ASCA at disease diagnosis can forecast the expensive CD patients. (Inflamm Bowel Dis 2007)


BMC Genomics | 2013

A colorectal cancer genome-wide association study in a Spanish cohort identifies two variants associated with colorectal cancer risk at 1p33 and 8p12

Ceres Fernandez-Rozadilla; Jean-Baptiste Cazier; Ian Tomlinson; Luis Carvajal-Carmona; Claire Palles; María Jesús Lamas; Montserrat Baiget; Luis A. Lopez-Fernandez; Alejandro Brea-Fernández; Anna Abulí; Luis Bujanda; Juan Clofent; Dolors González; Rosa M. Xicola; Montserrat Andreu; Xavier Bessa; Rodrigo Jover; Xavier Llor; Victor Moreno; Antoni Castells; Angel Carracedo; Sergi Castellví-Bel; Clara Ruiz-Ponte

BackgroundColorectal cancer (CRC) is a disease of complex aetiology, with much of the expected inherited risk being due to several common low risk variants. Genome-Wide Association Studies (GWAS) have identified 20 CRC risk variants. Nevertheless, these have only been able to explain part of the missing heritability. Moreover, these signals have only been inspected in populations of Northern European origin.ResultsThus, we followed the same approach in a Spanish cohort of 881 cases and 667 controls. Sixty-four variants at 24 loci were found to be associated with CRC at p-values <10-5. We therefore evaluated the 24 loci in another Spanish replication cohort (1481 cases and 1850 controls). Two of these SNPs, rs12080929 at 1p33 (Preplication=0.042; Ppooled=5.523x10-03; OR (CI95%)=0.866(0.782-0.959)) and rs11987193 at 8p12 (Preplication=0.039; Ppooled=6.985x10-5; OR (CI95%)=0.786(0.705-0.878)) were replicated in the second Phase, although they did not reach genome-wide statistical significance.ConclusionsWe have performed the first CRC GWAS in a Southern European population and by these means we were able to identify two new susceptibility variants at 1p33 and 8p12 loci. These two SNPs are located near the SLC5A9 and DUSP4 loci, respectively, which could be good functional candidates for the association signals. We therefore believe that these two markers constitute good candidates for CRC susceptibility loci and should be further evaluated in other larger datasets. Moreover, we highlight that were these two SNPs true susceptibility variants, they would constitute a decrease in the CRC missing heritability fraction.

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Rodrigo Jover

Spanish National Research Council

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Xavier Bessa

Pompeu Fabra University

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Angel Carracedo

University of Santiago de Compostela

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Luis Bujanda

University of the Basque Country

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Clara Ruiz-Ponte

University of Santiago de Compostela

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