Detection of metachronous neoplasms in colorectal cancer patients: identification of risk factors

PURPOSE

Patients with colorectal cancer have a high risk of developing metachronous neoplasms. Identification of predictive factors associated with such conditions would allow individualized follow-up strategies in these patients. This study was designed to identify individual and familial factors associated with the development of metachronous colorectal neoplasms in patients with colorectal cancer.

METHODS

In the context of a prospective, multicenter, general population-based study-the EPICOLON project-all patients with colorectal cancer attended in ten Spanish hospitals during a one-year period were included. Patients with familial adenomatous polyposis or inflammatory bowel disease were excluded. All patients were monitored by colonoscopy within two years of the diagnoses. Demographic, clinical, pathologic, molecular (microsatellite instability status and immunohistochemistry for MSH2 and MLH1), and familial characteristics (fulfillment of Amsterdam I or II criteria, and revised Bethesda guidelines) were analyzed.

RESULTS

A total of 353 patients were included in the study. At two years of follow-up, colonoscopy revealed the presence of adenomas in 89 (25 percent) patients and colorectal cancer in 14 (3.9 percent) patients, in 7 cases restricted to anastomosis. Univariate analysis demonstrated that development of metachronous neoplasm (adenoma or colorectal cancer) was associated with personal history of previous colorectal cancer (odds ratio, 5.58; 95 percent confidence interval, 1.01-31.01), and presence of previous or synchronous adenomas (odds ratio, 1.77; 95 percent confidence interval, 1.21-3.17). Although nonstatistical significance was achieved, metachronisms were associated with gender (P<0.09) and differentiation degree (P<0.08). Multivariate analysis identified previous or synchronous adenomas (odds ratio, 1.98; 95 percent confidence interval, 1.16-3.38) as independent predictive factor. Neither presence of tumor DNA microsatellite instability nor family history correlated with the presence of metachronous neoplasms.

CONCLUSIONS

Patients with previous or synchronous colorectal adenoma have an increased risk of developing metachronous colorectal neoplasms. Accordingly, this subgroup of patients may benefit from specific surveillance strategies.

Validation of the PREMM1,2 model for the prediction of MLH1/MSH2 germline mutation carriers in a population- based cohort of colorectal cancer (CRC) patients

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Background: PREMM1,2 is a predictive model for estimating the likelihood of finding a mutation in the MLH1 and MSH2 genes developed in a population at risk of Lynch syndrome (Balmaña et al. JAMA 2006). The EPICOLON cohort is a Spanish population-based series of 1222 patients with CRC (Piñol et al. JAMA 2005). Methods: All 1222 individuals underwent microsatellite instability (MSI) and immunohistochemistry (IHC) analysis for MLH1/MSH2. Patients whose tumours exhibited MSI or altered IHC underwent MLH1/MSH2 analysis (n=91). Sensitivity (Se), specificity, positive predictive value (PPV), and the areas under the receiver operating characteristics curves (AUC) for the PREMM1,2 model were calculated and compared with the Edinburgh model (Barnetson et al. NEJM 2006) and the Revised Bethesda guidelines (RBG). Results: Three-hundred and ninety six individuals (32%) had a PREMM1,2 score =5%, 287 (23%) fulfilled the RBG, and 75 (6%) had a Barnetson score =5%. A PREMM1,2 score =5% and the RBG identified all carriers with deleterious mutations (n=8, Se=100%), while a Barnetson score =5% missed 2 mutation carriers (Se= 75%). For PREMM1,2 and Barnetson scores =5% and fulfilment of the RBG, specificities were 68%, 94%, and 77%, respectively; and PPV were 2%, 8%, and 2.8%, respectively. The AUC was 0.93 (95% CI: 0.86–0.99) for the PREMM1,2 model and 0.86 (95% CI: 0.66–1.04) for the Barnetson model. The predictions of carrying a mutation stratified into five groups based on PREMM1,2 scores (<5%, 5–9%, 10–19%, 20–39%, =40%) correlated reasonably with the presence of mutations (0%, 1%, 1%, 13%, and 22%, respectively). Conclusions: In a population of CRC patients, the PREMM1,2 model identifies all mutation carriers of MSH2 and MLH1 using a cutoff of =5%. In addition, it provides quantification of risk that is useful to decide the strategy used for molecular evaluation and risk counselling of patients.

No significant financial relationships to disclose.

Association of the ARLTS1 Cys148Arg variant with sporadic and familial colorectal cancer

ARLTS1 was recently identified in chromosome 13q14 as a tumor suppressor gene of the ADP-ribosylation factor family with pro-apoptotic characteristics. Additionally, one of its genetic variants (W149X) was hypothesized to be a polymorphism associated with familial cancer. We performed a large case-control association study within the EPICOLON project aimed at evaluating the sporadic and familial colorectal cancer (CRC) risk associated with ARLTS1 genetic variants. Whereas P131L and W149X did not seem to affect CRC risk, C148R did show, for the first time in CRC, statistically significant differences between cases and controls [odds ratio (OR) = 1.45, 95% confidence interval (95% CI) = 1.13-1.86, P = 0.003], sporadic cases and controls (OR = 1.59, 95% CI = 1.13-2.23, P = 0.007) and familial cases and controls (OR = 1.55, 95% CI = 1.10-2.19, P = 0.01) in agreement with a hypothetical moderate increase of the cancer risk linked to the C148R ARLTS1 variant, both in sporadic and familial CRC cases.

Evaluation of 5 versus 10 granulocyteaphaeresis sessions in steroid-dependent ulcerative colitis: A pilot, prospective, multicenter, randomized study

AIM: To evaluate the efficacy of 5 compared to 10 granulocyteaphaeresis sessions in patients with active steroid-dependent ulcerative colitis.

METHODS: In this pilot, prospective, multicenter randomized trial, 20 patients with moderately active steroid-dependent ulcerative colitis were randomized to 5 or 10 granulocyteaphaeresis sessions. The primary objective was clinical remission at wk 17. Secondary measures included endoscopic remission and steroid consumption.

RESULTS: Nine patients were randomized to 5 granulocyteaphaeresis sessions (group 1) and 11 patients to 10 granulocyteaphaeresis sessions (group 2). At wk 17, 37.5% of patients in group 1 and 45.45% of patients in group 2 were in clinical remission. Clinical remission was accompanied by endoscopic remission in all cases. Eighty-six percent of patients achieving remission were steroid-free at wk 17. Daily steroid requirements were significantly lower in group 2. Eighty-nine per cent of patients remained in remission during a one year follow-up. One serious adverse event, not related to the study therapy, was reported.

CONCLUSION: Granulocyteaphaeresis is safe and effective for the treatment of steroid-dependent ulcerative colitis. In this population, increasing the number of aphaeresis sessions is not associated with higher remission rates, but affords a significant steroid-sparing effect.

Performance of different microsatellite marker panels for detection of mismatch repair-deficient colorectal tumors

BACKGROUND

Colorectal tumors caused by failure of the DNA mismatch repair system commonly show microsatellite instability. Our goals were to compare the performance of two panels of markers (a panel previously recommended by the National Cancer Institute [NCI] and a pentaplex of mononucleotide repeats) and to devise the simplest diagnostic strategy for identification of patients with colorectal cancer characterized by defects in mismatch repair.

METHODS

We recruited 1058 patients who were newly diagnosed with colorectal cancer. DNA from fresh-frozen and paraffin-embedded tumors was tested for microsatellite instability, using the NCI-recommended panel of microsatellite markers and the pentaplex panel of mononucleotide repeats, respectively, as templates for polymerase chain reactions (PCRs). Microsatellite instability in fresh-frozen tumors was also assessed using the pentaplex panel of mononucleotides in a crossover analysis. The expression of mismatch repair proteins (MLH1, MSH2, MSH6, and PMS2) in the tumors was determined immunohistochemically. The sensitivity and specificity with which the marker panels identified tumors with deficiencies in the expression of mismatch repair proteins were calculated. All statistical tests were two-sided.

RESULTS

The sensitivity and positive predictive value of the NCI panel were 76.5% (95% confidence interval [CI] = 61% to 92%) and 65.0% (95% CI = 49% to 81%), respectively; corresponding values for the mononucleotide pentaplex panel were 95.8% (95% CI = 89% to 103%) and 88.5% (95% CI = 79% to 98%), respectively. A panel consisting of the mononucleotide repeat markers BAT26 and NR24 alone had the same predictive value as the pentaplex panel of mononucleotide repeats.

CONCLUSIONS

The pentaplex panel of mononucleotide repeats performs better than the NCI panel for the detection of mismatch repair-deficient tumors. Simultaneous assessment of the instability of BAT26 and NR24 is as effective as use of the pentaplex panel for diagnosing mismatch repair deficiency.

Identification of MYH mutation carriers in colorectal cancer: a multicenter, case-control, population-based study

BACKGROUND & AIMS

Whereas it has conclusively been demonstrated that biallelic MutY human homolog (MYH) mutations confer a significant risk for colorectal cancer (CRC), the influence of monoallelic mutations remains controversial. Characterization of MYH-associated CRC is critical to identify individuals who might benefit from preventive strategies. This prospective, multicenter, case-control, population-based study was aimed at (1) establishing the CRC risk associated with specific germline MYH mutations and (2) devising a set of clinical criteria to identify MYH carriers among newly diagnosed CRC.

METHODS

Genotyping for Y165C and G382D was performed by TaqMan technology. Single-stranded conformation polymorphism analysis was performed in heterozygotes to screen for mutations in the entire gene. All individuals were re-screened for any additional pathogenic variant.

RESULTS

Biallelic and monoallelic MYH mutations were found in 8 (0.7%) and 19 (1.7%) of 1116 CRC patients, respectively. None of the 934 control subjects carried biallelic mutations, whereas 22 (2.3%) of them were monoallelic carriers. In a meta-analysis including all previous case-control studies, monoallelic MYH carriers were not at increased risk for CRC (odds ratio, 1.11; 95% confidence interval, 0.90-1.37), although a significant association was found with the Y165C mutation in either homozygotes or heterozygotes (odds ratio, 1.67; 95% confidence interval, 1.17-2.40). Furthermore, presence of more than 15 synchronous colorectal adenomas or CRC diagnosed before the age of 50 years was the most effective set of criteria for the identification of biallelic MYH mutation carriers.

CONCLUSIONS

This study proposes the first set of clinical criteria designed to identify CRC patients with biallelic MYH mutations, and it argues against an increased risk for monoallelic carriers.

Detection of BRAF V600E mutation in colorectal cancer: comparison of automatic sequencing and real-time chemistry methodology

Mutation V600E of BRAF, a kinase-encoding gene from the RAS/RAF/MAPK pathway, in colorectal carcinoma (CRC) suggests a sporadic origin of the disease, providing an exclusion criterion for hereditary nonpolyposis colorectal cancer. Here we describe detection of this mutation by real-time chemistry TaqMan MGB probes, confirmed by direct DNA sequencing as the gold standard. DNA was extracted from paraffin-embedded tissue from 112 tumors obtained from the EPICOLON study. Seventy-two tumors were CRC with defective DNA mismatch repair (MMR; microsatellite instability and/or loss of protein expression by immunohistochemical analysis), and 40 were proficient MMR controls. BRAF mutation was detected in 20/72 (27.8%) CRC with defective MMR and in 3/40 (7.5%) proficient MMR controls (P = 0.011). BRAF mutation was detected in 19/51 (37.3%) tumors with loss of MLH1 expression and in none of the tumors with loss of MSH2 expression (0/13). BRAF mutation was not found in cases with germline mutation of MLH1 (4/112) or MSH2 (3/112) genes. The sensitivity and specificity of our real-time chemistry were both 100% for detecting the V600E mutation. Because real-time chemistry methodology has advantages in cost, time, and labor, we consider it a valuable alternative to automatic direct sequencing, particularly for serial measurements.

Cyclooxygenase 2 expression in colorectal cancer with DNA mismatch repair deficiency

BACKGROUND

Cyclooxygenase 2 (COX-2) overexpression is a frequent but not universal event in colorectal cancer. It has been suggested that COX-2 protein expression is reduced in colorectal cancer with a defective mismatch repair (MMR) system, a phenomenon commonly associated with hereditary nonpolyposis colorectal cancer (HNPCC) but also present in up to 15% of sporadic tumors.

AIM

To assess COX-2 expression in a large series of fully characterized colorectal cancer patients with respect to the MMR system and to dissect the mechanisms responsible for altered COX-2 expression in this setting.

PATIENTS AND METHODS

MMR-deficient colorectal cancer were identified in a nationwide, prospective, multicenter study (EPICOLON project). Control MMR-proficient colorectal cancer patients were randomly selected. COX-2 expression was evaluated by immunohistochemistry. Personal and familial characteristics, as well as MSH2/MLH1 expression and germ line mutations, were evaluated.

RESULTS

One hundred fifty-three patients, 46 with MMR deficiency and 107 with MMR proficiency, were included in the analysis. Overall, tumor COX-2 overexpression was observed in 107 patients (70%). COX-2 overexpression was observed in 85 patients (79%) with a MMR-proficient system, but only in 22 patients (48%) with a MMR-deficient colorectal cancer (P < 0.001). The lack of COX-2 overexpression was independently associated with a MMR-deficient system (odds ratio, 3.89; 95% confidence interval, 1.78-8.51; P = 0.001) and a poor degree of differentiation (OR, 3.83; 95% CI, 1.30-11.31; P = 0.015). In the subset of patients with a MMR-deficient colorectal cancer, lack of COX-2 overexpression correlated with a poor degree of differentiation, no fulfillment of Amsterdam II criteria, absence of MSH2/MLH1 germ line mutations, presence of tumor MSH2 expression, and lack of tumor MLH1 expression. CpG island promoter hypermethylation of COX2 was observed in 6 of 18 (33%) tumors lacking COX-2 expression in comparison with 2 of 28 (7%) tumors expressing this protein (P = 0.04).

CONCLUSIONS

Up to half of MMR-deficient colorectal cancer do not show COX-2 overexpression, a fact observed almost exclusively in patients with sporadic forms. COX2 hypermethylation seems to be responsible for gene silencing in one third of them. These results suggest the potential utility of nonsteroidal anti-inflammatory drugs in HNPCC chemoprevention and may explain the lack of response of this approach in some sporadic tumors.

Chronic Chlamydia pneumoniae infection in patients with symptomatic atherothrombosis

OBJECTIVES

The aim of the present study was to search for an association between chronic Chlamydia pneumoniae infection, indicated by elevated antibody titers against the pathogen, atherothrombosis and the occurrence of arterial ischemic events.

METHODS

We studied 52 patients presenting at baseline with at least one symptomatic episode of atherothrombosis. A screening for fasting blood glucose and a lipid profile was performed on all patients who had no known history of diabetes or hypercholesterolemia.

RESULTS

The prevalence of IgG and IgA anti-C. pneumoniae antibodies at baseline was 90% (95% CI: 79-97) and 81% (67-90), respectively. Forty-two of the 52 patients (81%) experienced a new arterial ischemic event after a mean follow-up of 9 years [heart: 19 (37%); brain: 12 (23%); lower limbs: 8 (15%); and other: 13 (25%)]. Occurrence of a new arterial ischemic event was related to age (p=0.003), sex (p=0.009), and tobacco smoking (p=0.06). Prevalences of IgA and IgG anti-C. pneumoniae were significantly higher in patients with atherothrombosis at baseline than that in controls.

CONCLUSION

Our study confirmed the links between C. pneumoniae and atherothrombosis. However, neither IgA nor IgG antibodies for C. pneumoniae was a significant predictive factor for new ischemic arterial events in patients with atherothrombosis.

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

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.

Clinical performance of original and revised Bethesda guidelines for the identification of MSH2/MLH1 gene carriers in patients with newly diagnosed colorectal cancer: proposal of a new and simpler set of recommendations

Identification of individuals who should undergo hereditary nonpolyposis colorectal cancer (HNPCC) genetic testing is a critical and difficult issue. For this purpose, the National Cancer Institute outlined a set of recommendations, the Bethesda guidelines, which have recently been revised.

OBJECTIVE

To compare the clinical performance of original and revised Bethesda guidelines for the detection of MSH2/MLH1 gene carriers in patients with colorectal cancer.

METHODS

A total of 1,222 patients with newly diagnosed colorectal cancer were included in the EPICOLON study, a prospective, multicenter, nationwide epidemiology survey aimed at establishing the incidence of HNPCC in Spain (JAMA 2005; 293:1986-1994). Performance characteristics of the original and revised Bethesda guidelines were assessed with respect to the presence of MSH2/MLH1 germline mutations. Logistic regression analysis was performed to establish the most effective strategy.

RESULTS

Original or revised Bethesda guidelines were equivalent strategies in terms of sensitivity (100%vs 100%; ns), specificity (98.1%vs 97.9%; ns), and overall accuracy (98.1%vs 97.9%; ns), as well as positive (25.8%vs 24.2%) and negative predictive values (100%vs 100%). The most discriminating individual variables were criteria number 1 (i.e., fulfillment of the Amsterdam criteria; RR = 34.14; 95% CI = 6.85-170.16; p < 0.001) and number 2 (i.e., individuals with two HNPCC-related neoplasms; RR = 35.63; 95% CI = 4.83-262.6; p < 0.001) of the original guidelines, and criterion number 1 of the revised guidelines (i.e., colorectal cancer diagnosed under 50 yr of age; RR = 29.34; 95% CI = 3.81-225.96; p= 0.001). The aggregation of these three criteria was equivalent to both Bethesda guidelines in terms of sensitivity (100%) and negative predictive value (100%), but superior to the revised criteria regarding specificity (98.5%; p < 0.05), overall accuracy (98.5%; p < 0.05), and positive predictive value (30.8%).

CONCLUSIONS

Original and revised Bethesda guidelines are equivalent, highly effective criteria for the identification of MSH2/MLH1 gene mutation carriers in patients with newly diagnosed colorectal cancer. A new set of recommendations, based on a combination of some of their individual criteria, may provide additional advantages in terms of effectiveness.

[Endosonographic and manometric assessment of the internal anal sphincter in patients with chronic anal fissure]

INTRODUCTION

High anal resting pressures have been implicated in the pathophysiology of chronic anal fissure. It is not known, however, whether altered function is associated with any morphological abnormalities of the internal anal sphincter (IAS). The aims of the present study were to determine IAS thickness in patients with chronic anal fissure and to investigate the correlation between IAS thickness and anal resting pressure.

PATIENTS AND METHOD

Patients with chronic anal fissure were prospectively included between November 1999 and December 2002. Patients with a history of inflammatory bowel disease, anal surgery, and those previously treated with nitroglycerine ointment or botulinum toxin were excluded. Anal endosonography and manometry were performed. IAS thickness was considered to be increased when it was > 2.5 mm in patients < 50 years and > 3 mm in patients > or = 50 years. Anal resting pressure was considered to be increased when it was higher than 80 mmHg.

RESULTS

Sixty-three patients were analyzed. An abnormally thick IAS was observed in 58 patients (92%). The mean IAS thickness was 3.7 +/- 0.7 mm. IAS hypertonia was found in 47 patients (66%). The mean anal resting pressure was 91 +/- 28 mmHg. No correlation was found between IAS thickness and anal resting pressure (r = 0.05; p < 0.68).

CONCLUSIONS

Most of the patients with chronic anal fissure had an abnormally thick IAS. However, increased thickness of the IAS did not correlate with increased anal resting pressure.

Adaptation to Spanish language and validation of the fecal incontinence quality of life scale

PURPOSE

The aim of this study was to perform a psychometric evaluation of the Fecal Incontinence Quality of Life Scale in the Spanish language.

METHODS

Eleven hospitals in Spain participated in the study, which included 118 patients with active fecal incontinence. All the patients filled out a questionnaire on the severity of their incontinence, a general questionnaire of health (Medical Outcomes Survey Short Form), and a Spanish translation of the Fecal Incontinence Quality of Life Scale (Cuestionario de Calidad de Vida de Incontinencia Anal), which consists of 29 items in four domains: lifestyle, behavior, depression, and embarrassment. On a second visit, patients repeated the Fecal Incontinence Quality of Life Scale. For each domain, an evaluation was made of temporal reliability, internal reliability, the convergent validity with the generic questionnaire of health, and the discriminant validity correlating the domains of Cuestionario de Calidad de Vida de Incontinencia Anal with the severity of fecal incontinence.

RESULTS

For cultural adaptation, the answer alternatives for 14 items were modified. A total of 111 patients (94 percent) completed the study adequately. Temporal reliability (test-retest) was good for all domains except for embarrassment, which showed significant differences (P < 0.02). Internal reliability was good/excellent for all domains (Cronbach alpha >0.80, between 0.84 and 0.96). The four domains of Cuestionario de Calidad de Vida de Incontinencia Anal significantly correlated with the domains of the generic questionnaire on health (P < 0.01) and with the scale of severity of fecal incontinence (P < 0.001). All domains of Cuestionario de Calidad de Vida de Incontinencia Anal correlated negatively with the need to wear pads (P < 0.01) and with the presence of complete fecal incontinence.

CONCLUSIONS

The Cuestionario de Calidad de Vida de Incontinencia Anal incorporates sufficient requirements of reliability and validity to be applied to patients with fecal incontinence.

Role of Helicobacter pylori in stomach cancer after partial gastrectomy for benign ulcer disease

OBJECTIVE

To determine the prevalence of Helicobacter pylori infection in patients having undergone gastrectomy for non-neoplastic disease who later developed gastric stump cancer.

MATERIAL AND METHODS

Retrospective study of all patients with partial gastrectomy for non-malignant peptic disease who were submitted to an endoscopic exploration between 1995 and 2001. A comparison was made of major clinical and histological characteristics, and the presence of Helicobacter pylori among patients with and without gastric cancer in the stomach remnant.

RESULTS

A total of 73 patients were studied in this period. Fifteen patients (20.5%) had remnant-stump gastric cancer. All but one were adenocarcinomas (71% intestinal and 29% diffuse, respectively). The average time between diagnosis of gastric cancer and previous gastrectomy was 32 (14-48) years. There was a higher detection rate of Helicobacter pylori in patients with cancer in the gastric remnant (100 vs. 81.5%, respectively, p < 0.07). No relationship was seen between type of gastric reconstruction (Billroth I or II) and rate of Helicobacter pylori detection.

CONCLUSIONS

Helicobacter pylori infection is frequent in patients with previous gastrectomy for non-neoplastic disease. The results of the study suggest that Helicobacter pylori infection may play a role in gastric stump cancer.

Differential features of colorectal cancers fulfilling Amsterdam criteria without involvement of the mutator pathway

PURPOSE

Hereditary nonpolyposis colorectal cancer (HNPCC) is the commonest form of inherited colorectal cancer. Whereas it has been known that mismatch repair gene mutations are the underlying cause of HNPCC, an undetermined number of patients do not have these alterations. The main objectives of this study were to assess the relevance of clinically defined HNPCC patients without characteristic mutator pathway alterations and to identify their specific features.

EXPERIMENTAL DESIGN

This was a prospective, population-based, cohort that included 1,309 newly diagnosed colorectal cancer patients. Demographic, clinical, pathologic data and tumor DNA from probands as well as a detailed family history were collected. Microsatellite analysis and MLH1, MSH2, and MSH6 immunohistochemistry were done. Germ line MLH1 and MSH2 mutational analysis was done in all patients with evidence of MMR alterations.

RESULTS

Twenty-five patients (1.9%) fulfilled Amsterdam criteria of HNPCC but 15 (60%) of them did not have microsatellite instability and showed normal expression of MMR proteins. These patients presented mostly left-sided tumors without lymphocytic infiltrate; they were older, had fewer family members affected with colorectal or endometrial cancers, and more often fulfilled Amsterdam II criteria than HNPCC patients with microsatellite instability. Like unstable HNPCC patients, this group without mutator pathway alterations had a significant percentage of synchronous and metachronous adenomatous polyps and cancers.

CONCLUSIONS

We define an important group of HNPCC families with specific features, no evidence of mismatch repair deficiency, and an autosomal dominant trait with a lesser penetrance than HNPCC with deficiency.

Applicability of the Rockall score in patients undergoing endoscopic therapy for upper gastrointestinal bleeding

BACKGROUND

The Rockall score is used to assess the prognosis of patients with upper gastrointestinal bleeding.

AIM

To assess the applicability of the Rockall score in patients undergoing endoscopic therapy for upper gastrointestinal bleeding.

METHODS

Retrospective evaluation of the Rockall score in the period 1995-2001. To evaluate the applicability of the Rockall system, two groups were created: group I (Rockall<or=5 points) and group II (Rockall>or=6 points).

RESULTS

Two hundred and twenty-two patients were included. The median age of patients was 65 +/ -17 years. Hypotension and associated diseases were present in 20 and 50% of patients, respectively. Re-bleeding occurred in 50 patients (23%) whose median score was 7, whereas the median score of patients without re-bleeding was 6 (p=0.14). There were 20 deaths (9%) with a median score of 8, whilst the median score of surviving patients was 6 (p<0.001). Sixteen patients in group I (18.4%) and 34 in group II (25.2%) re-bled (p=0.25). All the patients who died belong to group II with a Rockall score>or=6 (15% versus 0% in groups II and I, respectively, p<0.001).

CONCLUSION

The Rockall score can be used in patients who undergo therapeutic endoscopy for upper gastrointestinal bleeding to identify those with high risk for mortality.

Genomic rearrangements in and are rare mutational events in Spanish patients with hereditary nonpolyposis colorectal cancer

Colorectal cancer (CRC) is one of the most common neoplasms and a leading cause of death related to cancer worldwide. Hereditary nonpolyposis colorectal cancer (HNPCC) is the most frequent autosomal dominant predisposition to the development of CRC, accounting for approximately 2.5% of the total CRC burden in Spain. Genomic rearrangements in the MSH2 and MLH1 genes have been reported to account for an important proportion of the mutation spectrum in HNPCC, and DNA dosage techniques have been developed facilitating molecular screening of such deletions/duplications. We screened for MSH2 and MLH1 genomic rearrangements by multiplex ligation-dependent probe amplification (MLPA) in 142 Spanish patients at risk for HNPCC prior to the exon-by-exon mutation scanning and found a deletion encompassing exons 9-16 of MSH2 and a duplication encompassing exons 11-16 of MSH2, both only in one case. These results showed that MSH2/MLH1 rearrangements in Spanish patients at risk for HNPCC seem to be a less frequent mutational event than in other populations.

A prospective trial comparing wireless capsule endoscopy and barium contrast series for small-bowel surveillance in hereditary GI polyposis syndromes

BACKGROUND

Capsule endoscopy has demonstrated its clinical utility in the evaluation of the small bowel, and, accordingly, it has been suggested that it could be useful for the identification of small-intestinal polyps in patients with polyposis syndromes. The objective was to establish the effectiveness of wireless capsule endoscopy for detecting small-bowel polyps in patients with hereditary GI polyposis syndromes in comparison with barium contrast series.

METHODS

Consecutive patients with GI polyposis syndromes were included. Small-bowel follow-through series and capsule endoscopy were performed within 1 week, in a blind fashion. The number and the location of polyps were analyzed.

RESULTS

Twenty-four patients with familial adenomatous polyposis (n = 20) or Peutz-Jeghers syndrome (n = 4) were included. Capsule endoscopy detected small-bowel polyps in 7 of 24 patients (29%), whereas a barium contrast study identified small-intestinal polyps in only 3 of these 7 patients. In the 4 remaining patients, all of them with familial adenomatous polyposis, polyps detected by the capsule but missed in radiographic series were located at either ileum (2 patients), jejunum (1), or duodenum (1). No procedure-related complication was observed in any patient.

CONCLUSIONS

Wireless capsule endoscopy is a highly accurate technique for the detection of small-bowel polyps in patients with hereditary GI polyposis syndromes, and it represents a valuable alternative to barium contrast series in the surveillance of patients with Peutz-Jeghers syndrome.

Accuracy of revised Bethesda guidelines, microsatellite instability, and immunohistochemistry for the identification of patients with hereditary nonpolyposis colorectal cancer

CONTEXT

The selection of individuals for hereditary nonpolyposis colorectal cancer (HNPCC) genetic testing is challenging. Recently, the National Cancer Institute outlined a new set of recommendations, the revised Bethesda guidelines, for the identification of individuals with HNPCC who should be tested for microsatellite instability.

OBJECTIVE

To establish the most effective and efficient strategy for the detection of MSH2/MLH1 gene carriers.

DESIGN, SETTING, AND PATIENTS

A prospective, multicenter, nationwide study (the EPICOLON study) in 20 hospitals in the general community in Spain of 1222 patients with newly diagnosed colorectal cancer between November 1, 2000, and October 31, 2001.

INTERVENTIONS

Microsatellite instability testing and MSH2/MLH1 immunostaining in all patients regardless of age, personal or family history, and tumor characteristics. Patients whose tumors exhibited microsatellite instability and/or lack of protein expression underwent MSH2/MLH1 germline testing.

MAIN OUTCOME MEASURES

Effectiveness and efficiency of both microsatellite instability testing and immunostaining, either directly or previous selection of patients according to the revised Bethesda guidelines, were evaluated with respect to the presence of MSH2/MLH1 germline mutations.

RESULTS

Two hundred eighty-seven patients (23.5%) fulfilled the revised Bethesda guidelines. Ninety-one patients (7.4%) had a mismatch repair deficiency, with tumors exhibiting either microsatellite instability (n = 83) or loss of protein expression (n = 81). Germline testing identified 11 mutations (0.9%) in either MSH2 (7 cases) or MLH1 (4 cases) genes. Strategies based on either microsatellite instability testing or immunostaining previous selection of patients according to the revised Bethesda guidelines were the most effective (sensitivity, 81.8% and 81.8%; specificity, 98.0% and 98.2%; positive predictive value, 27.3% and 29.0%, respectively) to identify MSH2/MLH1 gene carriers. Logistic regression analysis confirmed the revised Bethesda guidelines as the most discriminating set of clinical parameters (odds ratio, 33.3; 95% confidence interval, 4.3-250; P = .001).

CONCLUSION

The revised Bethesda guidelines constitute a useful approach to identify patients at risk for HNPCC. In patients fulfilling these criteria, both microsatellite instability testing and immunostaining are equivalent and highly effective strategies to further select those patients who should be tested for MSH2/MLH1 germline mutations.

[Helicobacter pylori and gastric cancer: relationship with histological subtype and tumor location]

INTRODUCTION

Helicobacter pylori (HP) has been implicated in the pathogenesis of gastric adenocarcinoma. Published data on HP infection and its association with both histological subtype and tumor localization are contradictory and few data are available on this topic in Spain. The aim of the present study was to evaluate the association of HP infection with histological subtype and tumor localization in a series of patients with gastric adenocarcinoma.

MATERIAL AND METHOD

We retrospectively reviewed all the patients diagnosed with gastric neoplasms in Hospital del Mar in Barcelona between 1995 and 2001. The histological subtype was established using Lauren's classification. Tissue samples were obtained from the surgical specimen or from endoscopic biopsies. HP infection was histologically determined through hematoxylin-eosin, Masson's trichromic, and Giemsa staining.

RESULTS

During the study period, 304 gastric neoplasms, 275 (90.4%) adenocarcinomas, 22 (7.2%) lymphomas, 3 (1.0%) leiomyosarcomas, 2 (0.7%) degenerated gastrointestinal stromal tumors (GIST) and 2 (0.7%) Kaposi's sarcomas were diagnosed. In patients with adenocarcinoma, the mean age at diagnosis was 69 years and most patients were male (62%). A total of 48.1% of the neoplasms were located in the gastric antrum, 23.7% in the body and 19.1% in the fundus (13.6% in the period 1994-1997 and 25.4% in the period 1998-2001, p = 0.018). Intestinal-type gastric carcinoma was observed in 56% of the patients, diffuse-type in 28% and indeterminate-type in 16%. HP infection was confirmed in 69% of the patients (68% in intestinal subtype, 69% in diffuse subtype, and 69% in indeterminate subtype, p = 0.84), and was significantly associated with distal adenocarcinomas vs. proximal adenocarcinomas (73.6% vs 48.6%, p < 0.05).

CONCLUSIONS

No differences were observed between the histological type of adenocarcinoma and HP infection. In the last few years, the incidence of fundic adenocarcinomas has increased. These tumors show a lower association with HP infection.

Cellular organization and appearance of differentiated structures in developing stages of the parasitic platyhelminthEchinococcus granulosus

Echinococcus granulosus is the causative agent of hydatidosis, a major zoonoses that affects humans and herbivorous domestic animals. The disease is caused by the pressure exerted on viscera by hydatid cysts that are formed upon ingestion of E. granulosus eggs excreted by canine. Protoscoleces, larval forms infective to canine, develop asynchronously and clonally from the germinal layer (GL) of hydatid cysts. In this report, we describe the cellular organization and the appearance of differentiated structures both in nascent buds and developed protoscoleces attached to the GL. Early protoscolex morphogenesis is a highly complex and dynamic process starting from the constitution of a foramen in the early bud, around which nuclei are distributed mainly at the lateral and apical regions. Similarly, distribution of nuclei in mature protoscoleces is not homogenous but underlies three cellular territories: the suckers, the rostellar pad, and the body, that surrounds the foramen. Several nuclei are associated to calcareous corpuscles (Cc), differentiated structures that are absent in the earlier bud stages. The number of nuclei is similar from the grown, elongated bud stage to the mature protoscolex attached to the GL, strongly suggesting that there is no significant cellular proliferation during final protoscolex development. The amount of DNA per nucleus is in the same range to the one described for most other platyhelminthes. Our results point to a sequential series of events involving cell proliferation, spatial cell organization, and differentiation, starting in early buds at the GL of fertile hydatid cysts leading to mature protoscoleces infective to canine.

Synchronous colorectal neoplasms in patients with colorectal cancer: predisposing individual and familial factors

PURPOSE

Patients with colorectal cancer have an increased risk for developing synchronous and metachronous neoplasms. However, besides those cases with inherited disorders predisposing to tumor multicentricity, it is unknown which patients are prone to this condition. This study was designed to identify individual and familial characteristics associated with the development of synchronous colorectal neoplasms in patients with colorectal cancer.

METHODS

During a one-year period, all patients with colorectal cancer attended in 25 Spanish hospitals were included. Exclusion criteria were colorectal cancer developed in the context of familial adenomatous polyposis or inflammatory bowel disease, refusal to participate in the study, incomplete family history, and inadequate examination of the colon and rectum. In addition to demographic, clinical, pathology, molecular (microsatellite instability status), and familial characteristics, presence of synchronous colorectal neoplasms (adenoma or carcinoma) were analyzed.

RESULTS

A total of 1,522 patients were included in the study. Synchronous colorectal neoplasms were documented in 505 patients (33.2 percent): adenoma (n = 411), carcinoma (n = 27), or both (n = 67). Development of these lesions was associated with male gender (odds ratio, 1.94; 95 percent confidence interval, 1.43-2.65), personal history of colorectal adenoma (odds ratio, 3.39; 95 percent confidence interval, 1.58-7.31), proximal location of primary tumor (odds ratio, 1.40; 95 percent confidence interval, 1.02-1.94), tumor TNM Stage II (odds ratio, 1.31; 95 percent confidence interval, 1.15-4.66), mucinous carcinoma (odds ratio, 1.89; 95 percent confidence interval, 1.19-2.99), and family history of gastric cancer (odds ratio, 2.03; 95 percent confidence interval, 1.17-3.52).

CONCLUSIONS

Based on individual and familial characteristics associated with synchronous colorectal neoplasms, it has been possible to identify a subgroup of patients with colorectal cancer prone to tumor multicentricity with potential implications on the delineation of preventive strategies.

Frequency of hereditary non-polyposis colorectal cancer and other colorectal cancer familial forms in Spain: a multicentre, prospective, nationwide study

BACKGROUND

Colorectal cancer is the third leading cause of cancer mortality in Western countries. Hereditary nonpolyposis colorectal cancer is the most common type of hereditary colorectal cancer, but its incidence remains controversial, ranging from 1 to 5%.

OBJECTIVE

This present prospective, multicentre, nationwide study was aimed at compiling prominent epidemiological and clinical data with respect to hereditary non-polyposis colorectal cancer and other familial colorectal cancer forms in Spain, where information is lacking.

METHODS

All patients with a de-novo diagnosis of colorectal cancer and who attended between November 2000 and October 2001 in 25 hospitals all over Spain were registered. Demographic, clinical and tumour-related characteristics of probands, and detailed family history, were obtained.

RESULTS

A total of 1872 colorectal cancer patients were included. Clinical diagnosis of hereditary non-polyposis colorectal cancer was established in 46 (2.5%) patients according to the Amsterdam II criteria. Comparison between patients fulfilling either the Amsterdam I or the Amsterdam II criteria revealed no differences with respect to demographic, clinical and tumour-related characteristics. A total of 504 (27.0%) patients had a family history of hereditary non-polyposis colorectal cancer-related neoplasm not fulfilling the Amsterdam criteria (familial colorectal cancer), while 360 (19.2%) patients fulfilled at least one of the Bethesda's criteria.

CONCLUSION

These clinicoepidemiological data provide a more accurate characterization of hereditary non-polyposis colorectal cancer and other familial colorectal cancer forms in Spain, with potential implications in preventive strategies.