Similarity of colorectal cancer in Crohn's disease and ulcerative colitis: implications for carcinogenesis and prevention

Advanced endoscopic imaging for surveillance for dysplasia and colorectal cancer in inflammatory bowel disease: could the pathologist be further helped?

Patients with inflammatory bowel disease (IBD) have an increased risk of developing intestinal cancer. The magnitude of that increased risk as well as how best to mitigate it remain a topic of ongoing investigation in the field. It is important to quantify the risk of colorectal cancer in association with IBD. The reported risk varies widely between studies. This is partly due to the different methodologies used in the studies. Because of the limitations of surveillance strategies based on the detection of dysplasia, advanced endoscopic imaging and techniques involving the detection of alterations in mucosal antigens and genetic abnormalities are being investigated. Development of new biomarkers, predicting future occurrence of colonic neoplasia may lead to more biomarker-based surveillance. There are promising results that may lead to more efficient surveillance in IBD patients and more general acceptance of its use. A multidisciplinary approach, involving in particular endoscopists and pathologists, together with a centralized patient management, could help to optimize treatments and follow-up measures, both of which could help to reduce the IBD-associated cancer risk.

Colorectal cancer in inflammatory bowel disease: results of the 3rd ECCO pathogenesis scientific workshop (I)

Epidemiological studies demonstrate an increased risk of colorectal cancer in patients with inflammatory bowel disease (IBD). A detailed literature review was conducted on epidemiology, risk factors, pathophysiology, chemoprevention and outcomes of colorectal cancer (CRC) in IBD as part of the 3rd ECCO scientific pathogenesis workshop.

A thirty-year follow-up surveillance study for neoplasia of a dutch ulcerative colitis cohort

BACKGROUND

Patients with ulcerative colitis have an increased risk of developing colorectal cancer (CRC). The aim of this study is to assess the yield of surveillance colonoscopies in a tertiary referral cohort of ulcerative colitis patients and to identify different risk groups for dysplasia.

METHODS

A cohort of 293 patients (148 males, mean age 33.8 years at diagnosis) was built up at our center and started the surveillance program 8-12 years after start of symptoms. They underwent colonoscopies every one to three years. Endpoints were dysplasia or a (sub)total colectomy.

RESULTS

After a follow-up period of 10 years, the cumulative incidence of any dysplasia was 23.5%, and of CRC 4.0%. After 15 years these percentages were 33.3% and 6.8%. Patients with pancolitis (n = 178) had a significantly higher cumulative risk of dysplasia than patients with distal disease, HR 1.9 (95%CI 1.1-3.3). Patients who started surveillance at an older age are at increased risk for any dysplasia, HR 1.03 (95%CI 1.01-1.05).

CONCLUSIONS

This prospective surveillance study shows a high yield of dysplasia in ulcerative colitis patients. We recommend developing separate surveillance programs for different risk groups. In our opinion patients with distal colitis can follow the general population surveillance program.

Preoperative pelvic radiation increases the risk for ileal pouch failure in patients with colitis-associated colorectal cancer

BACKGROUND AND AIMS

To evaluate the impact of preoperative radiation on pouch outcomes in patients with colitis-associated cancer (CAC).

METHODS

CAC patients who underwent restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) from 1984 to 2009 were identified from our registry. The impact of preoperative pelvic radiation for CAC or other pelvic cancer on pouch related outcomes was evaluated.

RESULTS

Sixty-three pouch patients with confirmed CAC were included (37 male, 58.7%). The mean age at pouch construction was 46.9±10.6 years. Seven patients were excluded due to the presence of persistent diverting ileostomy (n=2) or no follow-up (n=5). The remaining 56 patients were analyzed, including 9 who received pelvic radiation prior to IPAA creation for CRC or other cancers. Preoperative pelvic radiation was significantly associated with chronic pouchitis (P=0.024). There was, however, no correlation between pelvic radiation and pouch/anal transitional zone neoplasia, pouch stricture, pelvic abscess and pouch fistula/sinus. Pouch failure occurred in 13 patients after a median follow-up of 66.4 (range: 2.7-322.2) months. Although a simple statistical analysis based on the number of patients with pouch failure did not achieve significance (4/9 vs. 9/47, P=0.19), Kaplan-Meier analysis showed a strong association between preoperative pelvic radiation and the risk for pouch failure (P<0.001). A subgroup analysis of rectal cancer patients revealed that 3/7 patients (42.9%) with radiation and 3/17 (17.6%) without had pouch failure (P=0.31). Again, the association between pelvic radiation and pouch failure was confirmed using Kaplan-Meier analysis (P=0.02).

CONCLUSIONS

Pelvic radiation administered prior to IPAA creation appears to be associated with poor pouch outcomes. Oncological benefits and pouch functional outcomes should be carefully balanced before pelvic radiation is considered prior to restorative proctocolectomy.

The genetics of innate immunity sensors and human disease

Since their discovery, innate immunity microbial sensors have been increasingly studied and shown to play a critical role in innate responses to microbes in several experimental in vitro, ex vivo, and animal models. However, their role in the human response to infection in natural conditions has just started to be deciphered, by means of clinical studies of primary immunodeficiencies and epidemiological genetic studies. Here, we summarize the major findings concerning the genetic diversity of the various families of microbial sensors in humans, and of other molecules involved in the signaling pathways they trigger. Specifically, we review the genetic associations, revealed by both clinical and epidemiological genetics studies, of microbial sensors from five different families: Toll-like receptors, C-type lectin receptors, NOD-like receptors, RIG-I-like receptors, and cytosolic DNA sensors. In particular, we consider the relationships between variation at the genes encoding these molecules and susceptibility to and the severity of infectious diseases and other clinical conditions associated with immune dysfunction, including autoimmunity, inflammation, allergy, and cancer. Despite the fact that the genetic links between innate immunity sensors and human disorders remain still limited, human genetics studies are increasingly improving our understanding of the genuine functions of microbial sensors and downstream signaling molecules in the natural setting.

High rates of metachronous colon cancer or dysplasia after segmental resection or subtotal colectomy in Crohn's colitis

BACKGROUND

In ulcerative colitis, total proctocolectomy is the treatment of choice for patients with colonic dysplasia or cancer because of the high risk for metachronous neoplasia. It is unknown whether patients with Crohn's disease and colon cancer or dysplasia have a similar risk.

METHODS

We retrospectively reviewed the charts of 75 patients treated at our center from 2001 to 2011 with Crohn's disease and colon cancer who underwent segmental resection or subtotal colectomy (STC). We then identified the presence or absence of subsequent colon cancer or dysplasia in these patients during the follow-up (0-19 years).

RESULTS

Of the 64 patients with colon cancer, 25 had at least 1 metachronous cancer (39%). The mean time to a new cancer was 6.8 years. Eighty-five percent of patients (21/25) were undergoing annual screening colonoscopy. Of the 11 patients with dysplasia, 5 (46%) had a new dysplasia. Mean time to a new dysplastic lesion was 5.0 years. Nineteen of the 47 patients (40%) who had a segmental resection for colon cancer developed metachronous cancer and 6/17 patients (35%) with a STC had metachronous cancer. Two of the 4 patients (50%) with STC for dysplasia (50%) had a new dysplasia and 3/7 patients (43%) with segmental resection had a new dysplasia. There was no significant difference (P = 0.61) between recurrence rates in patients with segmental resection versus STC.

CONCLUSIONS

The high rate of metachronous colon cancer after surgical resection suggests that total proctocolectomy should be considered. Larger studies are required to determine if the same is true for dysplasia.

Risk of colorectal high-grade dysplasia and cancer in a prospective observational cohort of patients with inflammatory bowel disease

BACKGROUND & AIMS

There is an unclear risk of colonic high-grade dysplasia (HGD) and colorectal cancer (CRC) among patients with inflammatory bowel disease (IBD) treated with immunosuppressants. We analyzed data on CRC development among patients with IBD enrolled in the observational cohort Cancers et Surrisque Associé aux Maladies Inflammatoires Intestinales En France (CESAME).

METHODS

We followed and collected data from 19,486 patients with IBD (60.3% with Crohn's disease, 30.1% receiving thiopurine therapy) enrolled in CESAME from May 2004 and June 2005, and followed them until December 2007. When the study began, 2841 patients (14.6%) were characterized as having long-standing extensive colitis (ie, >10 years and involving ≥50% of the colon). Early lesions (HGD and CRC) were defined as those diagnosed within 10 years after diagnosis of IBD.

RESULTS

Thirty-seven patients developed CRC during the follow-up period, and 20 developed colorectal HGD. The standardized incidence ratios of CRC were 2.2 for all IBD patients (95% confidence interval [CI]: 1.5-3.0; P < .0001), 7.0 for patients with long-standing extensive colitis (95% CI: 4.4-10.5; P < .001), and 1.1 for patients without long-standing extensive colitis (95% CI: 0.6-1.8; P = .84). Among patients with long-standing extensive colitis, the multivariate adjusted hazard ratio for colorectal HGD and cancer was 0.28 for those who received thiopurines compared with those who never received thiopurine therapy (95% CI: 0.1-0.9; P = .03). Twenty-two patients developed early lesions; 7 of these were related to IBD, based on histologic analysis.

CONCLUSIONS

Patients with IBD and long-standing extensive colitis are at increased risk for CRC, although the risk is lower among patients receiving thiopurine therapy. Patients without long-standing extensive colitis have a risk for CRC similar to that of the general population, but they can develop IBD-related lesions within 10 years after diagnosis of IBD.

DNA methylation biomarkers for noninvasive diagnosis of colorectal cancer

DNA methylation biomarkers for noninvasive diagnosis of colorectal cancer (CRC) and precursor lesions have been extensively studied. Different panels have been reported attempting to improve current protocols in clinical practice, although no definite biomarkers have been established. In the present study, we have examined patient biopsies starting from a comprehensive analysis of DNA methylation differences between paired normal and tumor samples in known cancer-related genes aiming to select the best performing candidates informative for CRC diagnosis in stool samples. Five selected markers were considered for subsequent analyses in independent biologic cohorts and in silico data sets. Among the five selected genes, three of them (AGTR1, WNT2 and SLIT2) were validated in stool DNA of affected patients with a detection sensitivity of 78% [95% confidence interval (CI), 56%-89%]. As a reference, DNA methylation of VIM and SEPT9 was evaluated in a subset of stool samples yielding sensitivities of 55% and 20%, respectively. Moreover, our panel may complement histologic and endoscopic diagnosis of inflammatory bowel disease (IBD)-associated neoplasia, as it was also efficient detecting aberrant DNA methylation in non-neoplastic tissue samples from affected patients. This novel panel of specific methylation markers can be useful for early diagnosis of CRC using stool DNA and may help in the follow-up of high-risk patients with IBD.

The surgical treatment of inflammatory bowel disease-associated dysplasia

Surgical management of colonic dysplasia discovered in the inflammatory bowel disease patient is controversial. Total proctocolectomy (TPC) is the most definitive treatment for the eradication of undiagnosed synchronous dysplasias and/or carcinomas and the prevention of subsequent metachronous lesions in both Crohn's disease (CD) and ulcerative colitis (UC). However, TPC is not always an attractive option owing to patient comorbidities and patient preference. Historically, dysplasia has been most studied in patients with UC, where the option of reconstruction without a stoma makes TPC more acceptable. Due to a relative lack of research on CD-related dysplasia, surveillance and treatment of CD dysplasia has followed paradigms based on UC data. However, due to pathophysiological differences in CD versus UC, options for surgical management in CD may be more varied than simple TPC, particularly in the less healthy surgical candidate and those who refuse end ileostomy.

Polypectomy is adequate treatment for adenoma-like dysplastic lesions (DALMs) in Crohn's disease

BACKGROUND

The purpose of this study was to reevaluate the clinical and pathologic features and outcomes in patients with Crohn's disease with an adenoma-like dysplasia-associated lesion or mass (DALMs) to determine if polypectomy is adequate treatment.

METHODS

The clinical, endoscopic and pathologic features, and outcomes of 50 patients with Crohn's disease, each with ≥1 adenoma-like DALM were evaluated. The median length of follow-up was 39 months (range: 0.5-156 months).

RESULTS

Of the 50 patients with Crohn's disease (male to female ratio, 30:20; median age: 53 years; median duration of disease: 83 months), 11 had ileal disease, 26 had colonic disease, and 13 had both ileal and colonic disease. Approximately 43% of polyps occurred within areas of previous or concurrent colitis, whereas 57% occurred in areas not previously involved by colitis. Most polyps had tubular architecture and contained low-grade dysplasia. Of the patients who had polypectomy followed by surveillance, 45% developed new adenoma-like DALMs, but none developed flat dysplasia and only 1 had adenocarcinoma at the time of resection, which was within 3 months of polypectomy. There were no differences in the clinical or pathologic features or outcomes in patients who had adenoma-like DALMs within versus outside areas of previous or concurrent colitis, except that the former showed a higher risk of developing new polyps within areas of colitis and near the site of the original polyp compared with the latter.

CONCLUSIONS

Patients with Crohn's disease who develop an adenoma-like DALM, regardless of its location in relationship to previous or concurrent colitis, may be treated safely with polypectomy and continued surveillance.

Dysplastic lesions in inflammatory bowel disease: molecular pathogenesis to morphology

Context.-Inflammatory bowel disease (IBD) is a long-standing chronic active inflammatory process in the bowel with increased risk for the development of colorectal carcinoma. Several molecular events involved in chronic active inflammatory processes contribute to multistage progression of human cancer development, including reactive oxygen and nitrogen species, aberrant arachidonic acid metabolites and cytokines/growth factors, and immune dysfunction. These molecular events in IBD lead to genetic abnormality and promote aberrant cell proliferation, which further lead to epithelial changes encompassing a broad spectrum from inflammation-induced hyperplasia to dysplasia. Objective.-To review the (1) epidemiologic and molecular pathogenesis of the risk for colorectal cancer in IBD, (2) morphologic characterization, biomarker(s), and classification of dysplastic lesions, and (3) clinical management of dysplastic lesions arising in IBD. Data Sources.-The different IBD-related dysplastic lesions are illustrated by using morphology in conjunction with molecular pathways, and the "field cancerization" theory and its potential significance are discussed with a review of the literature. Conclusions.-Patients with IBD are at increased risk of developing colorectal cancer. The risk of developing carcinoma is related to the extent/duration/activity of the patient's disease. There is no consensus regarding the extent of carcinoma risk associated with IBD; however, all would agree that patients with IBD represent a group at significant risk for developing carcinoma and as such, warrant adequate surveillance and prevention. With better screening modalities and detection/characterization of dysplastic lesions, IBD-associated serrated lesions, and "field cancerization," we will improve our understanding of and approach to risk stratification.

Overview of molecular pathways in inflammatory bowel disease associated with colorectal cancer development

Patients with long-standing inflammatory bowel disease (IBD) are at a higher risk of developing colorectal cancer (CRC). This risk increases with the longer duration of colitis, greater extent of inflammation, a family history of CRC, severity of bowel inflammation, and a coexistent primary sclerosing cholangitis. The cornerstone for comprehending the development of CRC in IBD and hence early detection is based on the understanding of the molecular pathways of IBD itself. At a molecular level, the pathogenesis of CRC is related to understanding the inflammatory changes and involves multiple inter-related pathways including (i) genetic alterations (e.g. chromosomal and microsatellite instability and hypermethylation), (ii) mucosal inflammatory mediators (e.g. COX-2, interleukin-6, interleukin-23, tumor necrosis factor-α, nuclear factor-κB, and chemokines), (iii) changes in the expression of receptors on the epithelial cells, and (iv) oxidant stress, mucosal breakdown, and intestinal microbiota. The aim of this review is to provide an evidence-based approach for the role of chronic inflammatory mechanisms and the molecular basis of these mechanisms in the development of CRC. Therefore, understanding the molecular basis of CRC is an important step for the identification of new biomarkers that can help in the early detection of CRC in these patients.

Strategies for detecting colon cancer and dysplasia in patients with inflammatory bowel disease

The risk of colorectal cancer in patients with long-standing ulcerative colitis or colonic Crohn's disease is increased. Patients with long-standing ulcerative colitis are offered enrollment into programs of endoscopic surveillance. Although direct evidence for a protective effect of surveillance against death from colorectal cancer is limited, colorectal cancer is detected at an earlier stage and the corresponding prognosis is better. Targeting biopsies using pancolonic chromoendoscopy is superior to taking multiple random biopsies for the detection of dysplasia at colonoscopy.

Five-year mortality in colorectal cancer patients with ulcerative colitis or Crohn's disease: a nationwide population-based cohort study

BACKGROUND

The impact of inflammatory bowel disease (IBD) on colorectal cancer (CRC) prognosis, taking into account other comorbidities, is not clear. We studied the overall mortality in CRC patients with a history of ulcerative colitis (UC) or Crohn's disease (CD) compared with non-IBD-CRC patients.

METHODS

Data on all CRC and IBD patients diagnosed with CRC between 1977 and 2009 were retrieved from Danish medical registries. One-year and 5-year overall mortality were evaluated with the Kaplan-Meier method and with Cox regression, adjusting for year of CRC diagnosis, sex, Duke's stage, age at CRC diagnosis, and Charlson Comorbidity Index score.

RESULTS

We identified 653 CRC patients diagnosed with UC, 238 patients with CD, and 107,024 CRC patients without IBD. The patients with IBD were younger at diagnosis than patients without IBD. The Duke's stage distribution was similar for UC-CRC patients and non-IBD-CRC patients. The CD-CRC patients had a lower frequency of Duke's A and B stage tumors (36% versus 42%), a higher frequency of Duke's C stage tumors (31% versus 27%) and Duke's D-stage tumors (23% versus 21%), and a similar frequency of unknown stage tumors (10%) compared with non-IBD-CRC patients. After 5-years of follow-up, 59% of the UC and the non-UC-CRC patients had died compared with 62% of the patients with CD and 56% of the non-CD-CRC patients. The 5-year adjusted mortality rate ratios for patients with UC or CD were 1.14 (95% confidence interval, 1.03-1.27) and 1.26 (95% confidence interval, 1.07-1.49), respectively, compared with patients without IBD.

CONCLUSION

A history of IBD in patients with CRC may be associated with increased mortality.

Aberrant expression of circulating Th17, Th1 and Tc1 cells in patients with active and inactive ulcerative colitis

Ulcerative colitis (UC) is a chronic relapsing inflammatory bowel disease, yet its etiology and pathogenesis remain poorly understood. The aberrant expression of T lymphocytes plays an essential role in the progression of UC. This study aimed to evaluate the expression profile of circulating Th17, Th1 and Tc1 cells in patients with active and inactive UC. Our results revealed that the percentage of circulating Th17 cells (CD3+CD8-IL-17+) was significantly increased in patients with active UC when compared with the percentage in patients with inactive UC, Crohn's disease (CD) and healthy controls. The percentages of circulating Th1 (CD3+CD8-IFN-γ+) and Tc1 (CD3+CD8+IFN-γ+) cells were also higher in patients with active UC when compared with the percentages in patients with inactive UC and normal controls, although levels were lower than that in CD. Further analysis showed that Th17 cells were positively correlated with Th1 cells, but not with Tc1 cells. Notably, the three cells had a positive correlation with disease activity, extent of disease, detection of erythrocyte sedimentation rate and c-reactive protein in active UC. Moreover, plasma IL-17 was higher in patients with active UC, and a similar trend applied to the mRNA levels of RORγt and T-bet in peripheral blood mononuclear cells (PBMCs). The levels of p-STAT3 and p-STAT5 in PBMCs, as well as the ratio of p-STAT3/p-STAT5, were also elevated in active UC patients. Taken together, our findings revealed that elevated circulating Th17, Th1 and Tc1 cells and the aberrant activation of the STAT pathway may be implicated in the progression of UC. These findings may provide preliminary experimental clues for the development of new therapies for UC.

Novel methylation panel for the early detection of neoplasia in high-risk ulcerative colitis and Crohn's colitis patients

BACKGROUND

Patients with ulcerative colitis and Crohn's colonic disease are at increased risk of developing colorectal cancer (CRC). The aim of the study was to analyze the methylation status of selected genes as a risk marker for CRC in inflammatory bowel disease (IBD) patients.

METHODS

We evaluated the methylation status of four genes (TGFB2, SLIT2, HS3ST2, and TMEFF2) in biopsies of four groups of patients: 60 patients with sporadic CRC, 32 patients with IBD-associated neoplasia, 85 patients with IBD without associated neoplasia (20 at high risk and 65 at low risk), and 28 healthy controls. Methylation-specific melting curve analysis (MS-MCA) was used. Methylation status of these genes was also assessed in stool DNA from 60 IBD patients without neoplasia.

RESULTS

Methylation of the panel of genes analyzed was a very common phenomenon (78%) in IBD-associated neoplasia. The prevalence of methylation in adjacent nonneoplastic mucosa was also high (12/30). This prevalence was higher than in mucosa from healthy controls (2/28;7.1%; P < 0.05). Methylation of SLIT2 and TMEFF2 was more frequently detected in the mucosa of IBD patients at high risk of dysplasia or cancer (15/20) than patients at low risk (32/63) (P = 0.05 and P = 0.03, respectively). When stool samples were assessed, only SLIT2 gene methylation was more frequently methylated in the group of patients at high risk of dysplasia or cancer (4/16) compared to low risk (0/37) (P = 0.006).

CONCLUSIONS

Analysis of a panel of methylation markers may help in the early identification of colorectal dysplasia or cancer in high-risk IBD patients.

Cost-per-remission analysis of infliximab compared to adalimumab among adults with moderate-to-severe ulcerative colitis

OBJECTIVE

To compare cost per remission (CPR) of infliximab (IFX) versus adalimumab (ADA) for the treatment of moderately-to-severely active UC.

METHODS

This is CPR model comparing IFX and ADA in the treatment of UC using clinical trial data. Clinical outcome measures include clinical remission and sustained clinical remission (SCR). Economic endpoints were modeled as medication costs. CPR ratios and number needed to treat (NNT) costs were computed at 8, 52, and 54 weeks.

RESULTS

CPR for bio-naïve patients for IFX and ADA at weeks 8, 52, and 54 was $42,086 vs. $79,558: $147,379 vs. $320,097; $147,379 vs. $330,767, respectively. CPR for all patients for IFX and ADA at weeks 8, 52, and 54 was $42,086 vs. $113,812; $147,379 vs. $349,197; $147,379 vs. $360,836, respectively. Cost per SCR for bio-naïve patients and all patients for IFX and ADA was $203,205 vs. $682,873 and $203,205 vs. $698,393, respectively. NNT and NNT costs for clinical remission for bio-naïve patients at weeks 8, 52, and 54 were lower for IFX (4 vs.10, $40,235 vs. $81,945; 5 vs.10, $134,115 vs. $307,293; 5 vs. 10, $134,115 vs. $317,536, respectively) than for ADA. NNT and NNT costs for clinical remission for all patients at weeks 8, 52, and 54 were lower for IFX (4 vs.14, $40,235 vs. $114,723; 5 vs.11, $134,115 vs. $338,022; 5 vs. 11, $134,115 vs. $349,290, respectively) than for ADA. NNT and NNT costs for SCR for bio-naïve and all patients were lower for IFX (8 vs. 22, $214,584 vs. $676,045; 8 vs.23, $214,584 vs. $706,774) than for ADA. Study limitations include lack of head-to-head trial data, different primary endpoints between the two clinical trials, and indirect costs were not included.

CONCLUSION

IFX had lower CPR and cost per SCR than ADA in the treatment of moderately to severely active UC.

Direct health care insurer and out-of-pocket expenditures of inflammatory bowel disease: evidence from a US national survey

BACKGROUND

Crohn's disease (CD) and ulcerative colitis (UC) are chronic, debilitating conditions that can have important economic and clinical implications.

AIM

To quantify individual and national estimates of the health care and patient out-of-pocket (OOP) costs of CD and UC.

METHODS

In a retrospective study using 1996 to 2009 data from the Medical Expenditure Panel Survey, individuals' self-reported health conditions were mapped to International Classification of Diseases, Ninth Revision, Clinical Modification diagnostic codes. Individuals with a code of 555.x (CD) or 556.x (UC) were identified. Health care services and costs included prescriptions and inpatient, outpatient, emergency room, office, and home health services. OOP costs were the portion of individuals' total payments for health care services.

RESULTS

There were 358 individuals with CD (mean age 49.0 years; 55 % female), 198 individuals with UC (mean age 47.1 years; 64 % female), and 206,993 individuals without inflammatory bowel disease (IBD) (mean age 48.2 years; 58 % female). Annual per capita health insurer and OOP costs for individuals with CD were greater than those without IBD ($9,526 versus $3,781, p < 0.001 and $1,603 versus $866, p < 0.001, respectively). Health insurer and OOP costs were greater for UC compared with those without IBD ($6,443 versus $3,781, p < 0.001 and $1,263 versus $866, p < 0.001, respectively). US national aggregate annual estimates of health insurer, OOP, and total direct costs secondary to CD are $2.04 billion, $0.26 billion, and $2.29 billion, respectively. Aggregate health insurer, OOP, and total direct costs attributable to UC are $0.53 billion, $0.07 billion, and $0.61 billion, respectively.

CONCLUSIONS

The direct costs associated with CD and UC are substantial. The extent to which appropriate diagnosis and treatment reduces the total health care costs for individuals with CD or UC should be examined.

Keratins in colorectal epithelial function and disease

Keratins are the largest subgroup of intermediate filament proteins, which are an important constituent of the cellular cytoskeleton. The principally expressed keratins (K) of the intestinal epithelium are K8, K18 and K19. The specific keratin profile of a particular epithelium provides it with strength and integrity. In the colon, keratins have been shown to regulate electrolyte transport, likely by targeting ion transporters to their correct location in the colonocytes. Keratins are highly dynamic and are subject to post-translational modifications including phosphorylation, acetylation and glycosylation. These affect the filament dynamics and hence solubility of keratins and may contribute to protection against degradation. Keratin null mice (K8(-/-) ) develop colitis, and abnormal keratin mutations have been shown to be associated with inflammatory bowel disease (IBD). Abnormal expression of K7 and K20 has been noted in colitis-associated dysplasia and cancers. In sporadic colorectal cancers (CRCs) may be useful in predicting tumour prognosis; a low K20 expression is noted in CRCs with high microsatellite instability; and keratins have been noted as dysregulated in peri-adenomatous fields. Caspase-cleaved fragment of K18 (M30) in the serum of patients with CRC has been used as a marker of cancer load and to assess response to therapy. These data suggest an emerging importance of keratins in maintaining normal function of the gastrointestinal epithelium as well as being a marker of various colorectal diseases. This review will primarily focus on the biology of these proteins, physiological functions and alterations in IBD and CRCs.

Dysplasia associated with Crohn's colitis: segmental colectomy or more extended resection?

BACKGROUND AND OBJECTIVE

There is limited data on the appropriate management of dysplasia in Crohn's colitis. An evidence-based surgical strategy is provided.

METHODS

Patients with a pathologic diagnosis of dysplasia in Crohn's colitis from 1987 to 2009 were identified. Patients were classified by dysplasia grade (low grade or LGD, high grade or HGD). Clinical, endoscopic, operative, and pathologic data were retrieved. Factors associated with a final cancer diagnosis were analyzed. Survival data on patients undergoing limited versus radical resection for cancer and HGD was compared.

RESULTS

From 1987 to 2009, 50 patients underwent a colectomy for Crohn's colitis-associated dysplasia. The predictive value of HGD for a final HGD or cancer diagnosis was 73%. The predictive value of LGD on biopsy for HGD in the colectomy was 36%. Sixteen patients (44%) who underwent a total proctocolectomy (TPC) or subtotal colectomy (STC) had multifocal dysplasia. Four of 10 (40%) cancer patients had evidence of dysplasia remote from cancer site on pathologic examination. During follow-up, there were 3 cancer-related deaths. One patient died of metachronous cancer after STC.

CONCLUSIONS

The findings confirm the risk of cancer in patients with CD dysplasia. Because of the multifocal nature of dysplasia in Crohn's colitis, TPC is recommended in good-risk patients. In specific circumstances, such as poor-risk patients especially in the setting of LGD, close endoscopic surveillance or alternatively segmental or STC with close postoperative endoscopic surveillance, depending upon the individual circumstance, may be discussed.

Distinct clinicohistologic features of inflammatory bowel disease-associated colorectal adenocarcinoma: in comparison with sporadic microsatellite-stable and Lynch syndrome-related colorectal adenocarcinoma

Long-standing inflammatory bowel disease (IBD), either ulcerative colitis or Crohn disease, is associated with a high risk of developing colorectal adenocarcinoma (CAC). However, histomorphology of IBD-associated CAC has not been thoroughly examined, and it is unclear whether and how these patients should be screened for Lynch syndrome (LS). We evaluated the demographic and morphologic features of 108 IBD-associated CACs, including ulcerative colitis-associated (n = 95) and Crohn disease-associated CACs (n = 13), against 93 control cases of sporadic microsatellite-stable (MSS) CAC, 20 cases of sporadic microsatellite instability high (MSI-H) CAC, and 23 CAC cases of LS. The mean age of patients with IBD-associated CAC was 50 years, which was lower compared with the mean age of 63.7 years of the sporadic MSS controls and 76.5 years of the sporadic MSI-H group but not statistically different from that of the LS patients. Synchronous CACs were noted in 20.4% of the IBD patients and 13% of LS patients but in only 2.1% of the sporadic MSS controls and in none of the MSI-H patients. Right-sided CACs were significantly less frequent in the IBD group than in sporadic MSS controls, MSI-H group, and LS patients (P < 0.05 for all). In contrast to sporadic MSS CAC, IBD-associated CACs are characterized by lack of tumor necrosis, Crohn-like reaction, tumor histologic heterogeneity, the presence of mucin, and signet ring cell differentiation and tumor well differentiation. The histomorphologic similarity among IBD-associated and MSI-H tumors, either sporadic MSI-H or LS-related, is independent of MSI status. The young age of patients with IBD-associated CAC and the morphological similarities among IBD-associated, sporadic MSI-H, and LS-related CAC suggest that an age-based and morphology-based strategy before the screening test for LS may be less effective in IBD patients than in the non-IBD population.

Chronic psychosocial stress increases the risk for inflammation-related colon carcinogenesis in male mice

Patients with inflammatory bowel diseases (IBDs) have a higher risk of developing colorectal cancer (CRC) than the general population. Furthermore, chronic psychosocial stress increases the likelihood of developing IBD and multiple types of malignant neoplasms, including CRC. Here, for the first time, we investigate the effects of chronic psychosocial stress in male mice on an artificially induced CRC, by employing the chronic subordinate colony (CSC) housing paradigm in combination with the reliable azoxymethane (AOM)/dextran sodium sulfate (DSS) CRC model. Colonoscopy revealed that CSC mice showed accelerated macroscopic suspect lesions. In addition, more CSC mice developed low-grade dysplasia (LGD) and/or high-grade dysplasia (HGD) in the colonic tissue compared to the single-housed control mice (SHC). CSC mice showed an increased number of Ki67+ and a decreased number of terminal deoxynucleotidyl transferase dUTP nick end labeling epithelial cells in colonic tissue. Colonic liver receptor homolog-1 (LRH-1), cyclooxygenase II (COXII), tumor necrosis factor, forkhead box P3 (FoxP3) mRNA as well as colonic ß-catenin, COXII, and LRH-1 protein expression were also increased in CSC compared with SHC mice. Although the number of CD4+ Th cells was increased, a tendency toward a decreased colonic interferon-γ (IFN-γ) mRNA expression was observed. Furthermore, despite an increased percentage of CD3+ cells and CD3+/FoxP3+ double-positive cells within mesenteric lymph node cells of CSC mice, IFN-γ secretion from these cells was unaffected. Altogether, our results suggest that chronic psychosocial stress increases the risk for AOM/DSS-induced and, thus, inflammation-related CRC. Finally, assessment of additional time points may test whether the shift from tumor-protective Th1 cell to regulatory T-cell immunity represents a consequence of increased carcinogenesis or a causal factor involved in its development.

Colorectal cancer chemoprevention by mesalazine and its derivatives

Patients with inflammatory bowel disease (IBD) face an increased lifetime risk of developing colorectal cancer (CRC). Independent factors associated with increased risk include long disease duration, extensive colonic involvement, young age at onset of IBD, severity of inflammation, primary sclerosing cholangitis, backwash ileitis, and a family history of CRC, thus emphasising the role of intestinal inflammation as an underlying mechanism. This notion is also supported by the demonstration that the use of certain drugs used to attenuate the ongoing mucosal inflammation, such as mesalazine, seems to associate with a reduced incidence of colitis-associated CRC. In the last decade, work from many laboratories has contributed to delineate the mechanisms by which mesalazine alters CRC cell behaviour. In this paper, we review the available experimental data supporting the ability of mesalazine and its derivatives to interfere with intracellular signals involved in CRC cell growth.

Oral lichen planus as a preneoplastic inflammatory model

Oral lichen planus (OLP) is a chronic oral inflammatory disease of unknown etiology. According to reports, 1-2% of OLP patients develop oral squamous cell carcinoma (OSCC) in the long run. While World Health Organization (WHO) classifies OLP as “a potentially malignant disorder,” it is still a matter of debate which mechanisms drive OLP to such a condition. The current hypothesis connecting OLP and OSCC is that chronic inflammation results in crucial DNA damage which over time results in cancer development. Initial studies investigating the OLP and OSCC link were mainly retrospective clinical studies. Over the past years, several amount of information has accumulated, mainly from molecular studies on the OLP malignant potential. This article is a critical review of whether OLP has a malignant potential and, therefore, represents a model of preneoplastic inflammation.

3'-UTR and functional secretor haplotypes in mannose-binding lectin 2 are associated with increased colon cancer risk in African Americans

Because chronic intestinal inflammation is a risk factor for colorectal cancer, we hypothesized that genetic variants of inflammatory mediators, such as mannose-binding lectin 2 (MBL2), are associated with colon cancer susceptibility. Here, we report the association of 24 MBL2 single-nucleotide polymorphisms (SNP) and corresponding haplotypes with colon cancer risk in a case-control study. Four SNPs in the 3'-untranslated region (UTR) of the gene (rs10082466, rs2120132, rs2099902, and rs10450310) were associated with an increased risk of colon cancer in African Americans. ORs for homozygous variants versus wild-type ranged from 3.17 [95% confidence interval (CI), 1.57-6.40] to 4.51 (95% CI, 1.94-10.50), whereas the 3'-UTR region haplotype consisting of these four variants had an OR of 2.10 (95% CI, 1.42-3.12). The C allele of rs10082466 exhibited a binding affinity of miR-27a and this allele was associated with both lower MBL plasma levels and activity. We found that 5' secretor haplotypes known to correlate with moderate and low MBL serum levels exhibited associations with increased risk of colon cancer in African Americans, specifically as driven by two haplotypes, LYPA and LYQC, relative to the referent HYPA haplotype (LYPA: OR, 2.60; 95% CI, 1.33-5.08 and LYQC: OR, 2.28; 95% CI, 1.20-4.30). Similar associations were not observed in Caucasians. Together, our results support the hypothesis that genetic variations in MBL2 increase colon cancer susceptibility in African Americans.

Intestinal cancer in inflammatory bowel disease: natural history and surveillance guidelines

Inflammatory bowel diseases (IBD) are associated to an increased risk of colorectal cancer, which is primarily related to long-standing chronic inflammation. Recognized risk factors are the duration and extent of the disease, severe endoscopic and histological inflammation, primary sclerosing cholangitis, family history of colorectal cancer and in some studies young age at diagnosis. Recent population-based studies have shown that the risk is lower than previously described or even similar to that of the general population, and this could be justified by methodological aspects (hospital-based vs. population-based studies) or by a true decrease in the risk related to a better control of the disease, the use of drugs with chemoprotective effect or the spread of endoscopic surveillance in high-risk patients. Apart from colorectal cancer, patients with IBD are prone to other intestinal neoplasms (lymphoma, small bowel adenocarcinoma, pouch neoplasia and perianal neoplasia). In this article, the magnitude of the risk of intestinal cancer, the risk factors, the natural history of dysplasia and the recommendations of screening and surveillance in IBD are reviewed.

Inflammasomes and Intestinal Tumorigenesis

Colorectal cancer is a major health problem in developed countries. Chronic intestinal inflammation predisposes individuals to the development of colorectal cancer. The intracellular NOD-like receptors (NLRs) have emerged as crucial regulators of intestinal inflammation and colorectal tumorigenesis. Activation of several NLRs leads to the formation of a protein complex called the inflammasome, which then triggers the activation of the cysteine protease caspase-1 and the downstream maturation and secretion of the inflammatory cytokines interleukin-1β and -18. Defective inflammasome signaling in the gut contributes to colitis and colorectal tumorigenesis by increasing the permeability of the epithelial barrier, dysregulating the proliferation of epithelial cells, and inducing oncogenic mediators. In this review, we discuss our current knowledge on how the inflammasome protects against colorectal tumorigenesis.

Colorectal carcinoma in inflammatory bowel disease: a comparison between Crohn's and ulcerative colitis

AIM

The study assessed the clinicopathological features and survival rates of inflammatory bowel disease (IBD) patients with colorectal carcinoma (CRC), which accounts for ∼ 15% of all IBD associated death.

METHOD

The medical records of patients operated on for CRC in three institutions between 1992 and 2009 were reviewed, and those with Crohn's colitis (CC) and ulcerative colitis (UC) were identified. Data on age, gender, disease duration, colitis severity, surgical procedure, tumour stage and survival were retrieved.

RESULTS

Fifty-three patients (40 UC and 13 CC, 27 men, mean age at operation 54 years) were found. All parameters were comparable between the groups. Mean disease duration before CRC was 22.7 years for UC and 16.6 years for CC patients (P = 0.04). CRC was diagnosed preoperatively in 43 (81%) patients. Twenty-eight patients had colon cancer, 23 had rectal cancer and two patients had more than one cancer. All malignancies were located in segments with colitis. Over one-half were diagnosed at an advanced stage (36% stage III; 17% stage IV). At a mean follow up of 56 ± 65 months, 60% were alive (54% disease free) and 40% were dead from cancer-related causes. The 5-year survival rate was 61% for the UC and 37% for the CC patients (P = NS).

CONCLUSION

CRC in IBD patients is frequently diagnosed at an advanced stage, a factor that contributes to poor prognosis. The risk of CRC in CC patients is comparable to those with UC. Long-term surveillance is recommended for patients with long-standing CC and UC.

The role of N-acetyltransferase 2 polymorphism in the etiopathogenesis of inflammatory bowel disease

BACKGROUND AND PURPOSE

Inflammatory bowel disease (IBD) consists of ulcerative colitis (UC) and Crohn's disease (CD), which are complex genetic disorders resulting from the interplay between several genetic and environmental risk factors. The arylamine N-acetyltransferase 2 (NAT2) enzyme detoxifies a wide spectrum of naturally occurring xenobiotics including carcinogens and drugs. Acetylation catalyzed by NAT2 is an important process in metabolic activation of arylamines to electrophilic intermediates that initiate carcinogenesis. The aim of our study was to determine whether there is any association between the susceptibility to inflammatory bowel disease among the variations of NAT2 genotypes.

METHODS

This study was carried out in 80 patients with IBD. The control group consisted of 100 healthy volunteers. The most common mutations found in the Caucasian population are at the positions 481T, 803G, 590A and 857A on the NAT2 gene. This was determined using the polymerase chain reaction-restriction fragment length polymorphism method with DNA extracted from peripheral blood.

RESULTS

Risk of IBD development was 3.86 for the carriers of the NAT2*5/NAT2*7 genotype and 2.53 for the carriers with NAT2*6/NAT2*7, but it was not statistically significant. A statistically significant correlation between the NAT2*7 allele prevalence and the risk for developing IBD was found (OR = 5.8; P = 0.005).

CONCLUSIONS

Higher prevalence of the NAT2*7 allele in patients with IBD and the obtained OR values could suggest that this mutation has the effect of increasing IBD development. Future studies are needed to confirm our assumptions on larger group of patients.

Low prevalence of colonoscopic surveillance of inflammatory bowel disease patients with longstanding extensive colitis: a clinical practice survey nested in the CESAME cohort

BACKGROUND

Surveillance colonoscopy is recommended for inflammatory bowel disease (IBD) patients with longstanding extensive colitis (LEC).

AIMS

To assess modalities and results of colonoscopic surveillance in a subset of CESAME cohort patients at high risk of colorectal cancer (CRC) and followed in university French hospitals.

METHODS

Among 910 eligible patients with more than a 7-year history of extensive colitis at CESAME enrolment, 685 patients completed a questionnaire on surveillance colonoscopy and 102 were excluded because of prior proctocolectomy. Finally, 583 patients provided information spanning a median period of 41months (IQR 38-43) between cohort enrolment and the end of follow-up. Details of the colonoscopic procedures and histological findings were obtained for 440 colonoscopies in 270 patients.

RESULTS

Only 54% (n=312) of the patients with LEC had at least one surveillance colonoscopy during the study period, with marked variations across the nine participating centres (27% to 70%, P≤0.0001). Surveillance rate was significantly lower in Crohn's colitis than in ulcerative colitis (UC) (48% vs. 69%, P≤0.0001). Independent predictors of colonoscopic surveillance were male gender, UC IBD subtype, longer disease duration, previous history of CRC and disease management in a centre with large IBD population. Random biopsies, targeted biopsies and chromoendoscopy were performed during respectively 71%, 27 and 30% of surveillance colonoscopies. Two cases of high-grade dysplasia were detected in patients undergoing colonoscopic surveillance. Two advanced-stage CRC were diagnosed in patients who did not have colonosocopic surveillance.

CONCLUSIONS

Colonoscopic surveillance rate is low in IBD patients with longstanding extensive colitis.

Current management of inflammatory bowel disease and colorectal cancer

INFLAMMATORY BOWEL DISEASES (IBDS) CAN BE DIVIDED INTO TWO MAJOR DISORDERS: ulcerative colitis and Crohn's disease. Although IBD-associated colorectal cancer (IBD-CRC) accounts for only 1-2% of all cases of colorectal cancer, IBD with colon involvement is among the top three high-risk conditions for colorectal cancer. Today, colorectal cancer accounts for approximately 10-15% of all deaths among IBD patients. Indeed, patients with IBD colitis are six times more likely to develop colorectal cancer than the general population and have a higher frequency of multiple synchronous colorectal cancers. Since IBD-CRC was first described in 1925, the colon remains the primary site of neoplasms in IBD patients today. Ulcerative colitis-associated colorectal cancer is most common in the rectum and sigmoid colon, whereas Crohn's disease-associated colorectal cancer is evenly distributed between the different colon segments. Chemoprevention of colorectal cancer remains an important goal, and colonoscopy surveillance programs are critical to early detection in these patients. Newer methods, such as chromoendoscopy, are currently being investigated as complementary techniques to enhance early detection of dysplasia and cancer in this high-risk population. We present a comprehensive review of the relationship between inflammatory bowel disease and colorectal cancer. Major themes covered include risk factors for IBD-CRC and the molecular pathobiology of progression from dysplasia to cancer, endoscopic surveillance and new methods for early detection of dysplasia, approaches to prevention of IBD-CRC, and current recommendations and controversies regarding the treatment of dysplasia. In particular, disagreement has arisen over optimal management of low-grade dysplasia, with some IBD experts now advocating close colonoscopic surveillance of patients with low-grade dysplasia rather then total colectomy.

Inflammatory bowel disease-associated colorectal cancer: proctocolectomy and mucosectomy do not necessarily eliminate pouch-related cancer incidences

BACKGROUND

Colorectal cancer (CRC), the most lethal long-term complication of inflammatory bowel disease (IBD), is the culmination of a complex sequence of molecular and histologic derangements of the colon epithelium that are initiated and at least partially sustained by prolonged chronic inflammation. Dysplasia, the earliest histologic manifestation of this process, plays an important role in cancer prevention by providing the first clinical alert that this sequence is under way and by serving as an endpoint in colonoscopic surveillance of patients at high risk for CRC. Restorative proctocolectomy (RPC) is indicated for patients with IBD, specifically for ulcerative colitis that is refractory to medical treatment, emergency conditions, and/or in case of neoplastic transformation. Even after RPC with mucosectomy, pouch-related carcinomas have recently been reported with increasing frequency since the first report in 1984. We review IBD-associated CRC and pouch-related neoplasia prevalence, adverse events, risk factors, and surveillances.

METHODS

Literature of IBD-associated CRC patients and those undergoing RPC surgeries through 2010 were prospectively reviewed.

RESULTS

We found 12 studies from retrospective series and 15 case reports. To date, there are 43 reported cases of pouch-related cancers. Thirty-two patients had cancer in the anal transit zone (ATZ); of these, 28 patients had mucosectomy. Eleven patients had cancer found in the pouch body.

CONCLUSION

RPC with mucosectomy does not necessarily eliminate risks. There is little evidence to support routine surveillance of pouch mucosa and the ATZ except for patients associated with histological type C changes, sclerosing cholangitis, and unremitting pouchitis.

Risk of colorectal cancer in self-reported inflammatory bowel disease and modification of risk by statin and NSAID use

BACKGROUND

Statins and nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with reduced risk of colorectal cancer (CRC) in some studies. The objective of this study was to quantify the relative risk of inflammatory bowel disease (IBD) as a risk factor for CRC and to estimate whether this risk may be modified by long-term use of NSAIDs or statins.

METHODS

The Molecular Epidemiology of Colorectal Cancer study is a population-based, case-control study of incident colorectal cancer in northern Israel and controls matched by age, sex, clinic, and ethnicity. Personal histories of IBD and medication use were measured by structured, in-person interview. The relative risk of IBD and effect modification by statins and NSAIDs were quantified by conditional and unconditional logistic regression.

RESULTS

Among 1921 matched pairs of CRC cases and controls, a self-reported history of IBD was associated with a 1.9-fold increased risk of CRC (95% confidence interval [CI], 1.12-3.26). Long-term statin use was associated with a reduced risk of both IBD-associated CRC (odds ratio [OR] = 0.07; 95% CI, 0.01-0.78) and non-IBD CRC (OR = 0.49; 95% CI, 0.39-0.62). Stratified analysis suggested that statins may be more protective among those with IBD (ratio of OR = 0.14; 95% CI, 0.01-1.31; P = .51), although not statistically significant. NSAID use in patients with a history of IBD was suggestive of reduced risk of CRC but did not reach statistical significance (OR = 0.47; 95% CI, 0.12-1.86).

CONCLUSIONS

The risk of CRC was elevated 1.9-fold in patients with IBD. Long-term statin use was associated with reduced risk of CRC in patients with IBD.

Intestinal cancer risk in Crohn's disease: a meta-analysis

AIM OF THE STUDY

To clarify the intestinal cancer risk in Crohn's disease (CD).

METHODS

20 clinical studies (1965-2008) with a total of 40,547 patients with Crohn's disease-associated cancer (CDAC) were included in the meta-analysis ("inverse variance weighted" method).

RESULTS

The incidence of CDAC in any CD patient was 0.8/1,000 person years duration (pyd) (CI, 0.6-1.0). The incidences of different carcinomas were: colorectal cancer 0.5/1,000 pyd (CI, 0.3-0.6), small bowel carcinoma 0.3/1,000 pyd (CI, 0.1-0.5), and cancers arising from CD-associated fistulae 0.2/1,000 pyd (CI, 0.0-0.4). Compared to the incidence in an age-matched standard population, the risk of colorectal cancer was increased by factor 2-3 and of small bowel cancer by factor 18.75, respectively. Mean patient age at diagnosis of CD-associated colorectal cancer was 51.5 years, thus 20 years earlier than in a standard population. The mean duration of CD until diagnosis of CDAC was 18.3 years. Duration of CD, age at diagnosis of CD, and anatomical area of CD involvement had no significant influence on cancer incidence.

CONCLUSIONS

CD is a risk factor for colorectal cancer, small bowel cancer, and fistula cancer; however, compared to ulcerative colitis, cancer risk is moderate.

Noninvasive detection of inflammation-associated colon cancer in a mouse model

Helicobacter bilis-infected Smad3(-/-) mice represent an attractive model of inflammation-associated colon cancer. Most infected mice develop mucinous adenocarcinoma (MUC) by 6 weeks post inoculation (PI); however, approximately one third do not progress to MUC. The ability to predict the development of MUC in mice used in therapeutic studies would confer a considerable saving of time and money. In addition, the inadvertent use of mice without MUC may confound therapeutic studies by making treatments seem falsely efficacious. We assessed both magnetic resonance imaging (MRI) and fecal biomarkers in Helicobacter- and sham-inoculated mice as methods of noninvasively detecting MUC before the predicted onset of disease. Non-contrast-enhanced MRI was able to detect lesions in 58% of mice with histologically confirmed MUC; however, serial imaging sessions produced inconsistent results. MRI was also a labor- and time-intensive technique requiring anesthesia. Alternatively, inflammatory biomarkers isolated from feces at early time points were correlated to later histologic lesions. Fecal expression of interleukin 1β, macrophage inflammatory protein 1α, and regulated on activation, normal T-cell expressed, and secreted at 3 weeks PI correlated significantly with lesion severity at 9 weeks PI. For each biomarker, receiver-operator characteristic curves were also generated, and all three biomarkers performed well at 1 to 3 weeks PI, indicating that the development of MUC can be predicted based on the early expression of certain inflammatory mediators in feces.

Role of the endothelium in inflammatory bowel diseases

Inflammatory bowel diseases (IBD) are a complex group of diseases involving alterations in mucosal immunity and gastrointestinal physiology during both initiation and progressive phases of the disease. At the core of these alterations are endothelial cells, whose continual adjustments in structure and function coordinate vascular supply, immune cell emigration, and regulation of the tissue environment. Expansion of the endothelium in IBD (angiogenesis), mediated by inflammatory growth factors, cytokines and chemokines, is a hallmark of active gut disease and is closely related to disease severity. The endothelium in newly formed or inflamed vessels differs from that in normal vessels in the production of and response to inflammatory cytokines, growth factors, and adhesion molecules, altering coagulant capacity, barrier function and blood cell recruitment in injury. This review examines the roles of the endothelium in the initiation and propagation of IBD pathology and distinctive features of the intestinal endothelium contributing to these conditions.

Signet-ring cell carcinoma of colorectum--current perspectives and molecular biology

PURPOSE

Colorectal signet-ring cell carcinoma (SRCC) is rare, and very little detailed information on the molecular biology of the disease is available.

METHODS

The literature on the clinical, pathological and, in particular, the molecular biology of this rare entity was critically reviewed. The reviewed articles take into account a total of 1,817 cases of SRCC, but only 143 cases have molecular data available. The characteristics of two patients with colorectal SRCC were also discussed.

RESULTS

Colorectal SRCC mostly occurs in younger patients, is larger and has different site predilection compared with conventional colorectal adenocarcinoma. It can occur as one of the synchronous cancers in the colorectum. The cancer is usually diagnosed at advanced stages because of the late manifestation of symptoms, and aggressive treatment strategy is required. Limited reports in the literature have shown that the variant of colorectal cancer demonstrated a different pattern of genetic alterations of common growth kinase-related oncogenes (K-ras, BRAF), tumour suppressor genes (p53, p16), gene methylation and cell adhesion-related genes related to the Wingless signalling pathway (E-cadherin and beta-catenin) from conventional colorectal adenocarcinoma. Colorectal SRCC also showed high expression of mucin-related genes and genes related to the gastrointestinal system. There was also a higher prevalence of microsatellite instability-high tumours and low Cox-2 expression in colorectal SRCC as opposed to conventional adenocarcinoma.

CONCLUSIONS

Colorectal SRCC has unique molecular pathological features. The unique molecular profiles in SRCC may provide molecular-based improvements to patient management in colorectal SRCC.

Dysplasia and cancer in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic gastrointestinal disease associated with an increased risk of colorectal cancer (CRC). Although CRC occurs in a minority of IBD patients (1%), it carries a high mortality and accounts for 20% of IBD-related mortality. Established risk factors for the development of CRC in IBD include disease duration of 8 years or more, family history of CRC, extensive colitis and primary sclerosing cholangitis. Meticulous colonoscopy and anti-inflammatory medications can reduce the risk of developing CRC. The future of IBD surveillance involves the use of novel endoscopic techniques (chromoendoscopy, narrow-band imaging, confocal laser endomicroscopy and autofluorescence) to enhance colonoscopic accuracy, in concert with chemopreventative medications to help reduce the risk of CRC in IBD.

The association of Streptococcus bovis/gallolyticus with colorectal tumors: the nature and the underlying mechanisms of its etiological role

Streptococcus bovis (S. bovis) bacteria are associated with colorectal cancer and adenoma. S. bovis is currently named S. gallolyticus. 25 to 80% of patients with S. bovis/gallolyticus bacteremia have concomitant colorectal tumors. Colonic neoplasia may arise years after the presentation of bacteremia or infectious endocarditis of S. bovis/gallolyticus. The presence of S. bovis/gallolyticus bacteremia and/or endocarditis is also related to the presence of villous or tubular-villous adenomas in the large intestine. In addition, serological relationship of S. gallolyticus with colorectal tumors and direct colonization of S. gallolyticus in tissues of colorectal tumors were found. However, this association is still under controversy and has long been underestimated. Moreover, the etiological versus non-etiological nature of this associationis not settled yet. Therefore, by covering the most of up to date studies, this review attempts to clarify the nature and the core of S. bovis/gallolyicus association with colorectal tumors and analyze the possible underlying mechanisms.

Does the prognosis of colorectal cancer vary with tumor site?

AIM

The aim of this study was to compare prognostic factors between colon and rectal cancers.

BACKGROUND

Prognosis of Colorectal Cancer (CRC) may depend on the anatomical site.

PATIENTS AND METHODS

A total of 1219 patients with CRC diagnosis according to the pathology report of RCGLD cancer registry, from 1 January 2002 to 1 October 2007, were entered into the study. Demographic and clinico-pathological factors were analyzed using survival analysis.

RESULTS

From age at diagnosis, colon cancer had significantly better survival than rectal cancer (Multivariate Hazard Ratio (MVHR)=0.24; 95% Confidence Interval (CI) =(0.074-0.77)). Other factors, including marital status (MVHR =1.78; 95% CI =(0.33-9.62)), body mass index (BMI) (MVHR =1.21 and 1.54; 95% CI =(.30-4.85) and (.44-5.4) respectively for < 18.5 and >30 BMI groups), pathologic stage (MVHR =.64; 95% CI =(.21-1.98)) and alcohol history (MVHR =4.86; 95% CI =(.67-35.14)) were not significantly different between the two patient group but suggested a possible effect upon prognosis. Overall survival in rectum was better than that of colon.

CONCLUSION

Our findings support this hypothesis that prognosis of CRC varies with tumor site.

Clinical presentation and diagnosis of intestinal adenocarcinoma in Crohn's disease: analysis of clinical predictors and of the life-time risk

BACKGROUND

Late diagnosis of cancer in CD often occurs, and the prognosis is poor. The primary aim of this study was to assess the relationship between clinical presentation and diagnosis of intestinal adenocarcinoma in CD; the secondary aim was to evaluate the timing of cancer occurrence in CD patients.

PATIENTS AND METHODS

Medical records of 12 consecutive patients with intestinal adenocarcinoma in CD and of 79 consecutive CD patients undergoing bowel surgery were reviewed. Presentation symptoms were analyzed as possible predictors. Timing of intestinal adenocarcinoma occurrence in patients with CD was analyzed including all the 347 consecutive patients that had undergone surgery for CD in our institute from January 1984 to June 2008. Life table analysis and uni/multivariate analyses were performed.

RESULTS

Ten men and two women underwent surgery for intestinal cancer in CD with a median age of 50 years (31-68). Carcinomas were localized in the terminal ileum in four cases, right colon in three, transverse colon in one, sigmoid colon in one, rectum in two, and an anorectal fistula in one. Only three patients were pre-operatively diagnosed with cancer. At multivariate analysis only age (OR 1.057 (95% CI 0.999-1.107), p = 0.05) and obstruction (OR 6.530 (95% CI 1.533-27.806), p = 0.01) significantly predicted cancer diagnosis. The risk rate (RR) for cancer occurrence started to rise at the end of the third decade of life (RR = 0.005). The analysis of risk rate for cancer occurrence during overt CD showed that it is initially high at onset (RR = 0.001) and after two other peaks at 150 months from onset, it began to rise again. The presence of Crohn's colitis was associated to a significant risk of cancer (HR = 4.790, p = 0.009) while the use of 5-ASA resulted to be a protective factor against cancer occurrence (HR = 0.122, p = 0.013).

DISCUSSION

In CD, rectal bleeding, the most common alarm symptom for intestinal cancer, is not useful for an early diagnosis. CD patients presenting with an older age and obstruction should be thoroughly investigated to rule out neoplastic lesions. There is probably no safe interval of CD where surveillance for intestinal cancer can be omitted. In the meantime, even in absence of active disease, all CD patients should undergo therapy with 5-ASA.

IL-18 production downstream of the Nlrp3 inflammasome confers protection against colorectal tumor formation

Colorectal cancer is a leading cause of cancer-related deaths worldwide. Chronic inflammation is recognized as a predisposing factor for the development of colon cancer, but the molecular mechanisms linking inflammation and tumorigenesis have remained elusive. Recent studies revealed a crucial role for the NOD-like receptor protein Nlrp3 in regulating inflammation through the assembly of proinflammatory protein complexes termed inflammasomes. However, its role in colorectal tumor formation remains unclear. In this study, we showed that mice deficient for Nlrp3 or the inflammasome effector caspase-1 were highly susceptible to azoxymethane/dextran sodium sulfate-induced inflammation and suffered from dramatically increased tumor burdens in the colon. This was a consequence of markedly reduced IL-18 levels in mice lacking components of the Nlrp3 inflammasome, which led to impaired production and activation of the tumor suppressors IFN-γ and STAT1, respectively. Thus, IL-18 production downstream of the Nlrp3 inflammasome is critically involved in protection against colorectal tumorigenesis.

Colorectal cancer complicating inflammatory bowel disease: similarities and differences between Crohn's and ulcerative colitis based on three decades of experience

INTRODUCTION

The aim of this study was to evaluate patient- and tumor-related characteristics for patients undergoing surgery for cancer complicating inflammatory bowel disease (IBD), and to assess differences between patients with Crohn's disease (CD) and ulcerative colitis (UC).

METHODS

Data on all IBD patients with colon and rectal cancer (CRC) undergoing surgery between 1980 and 2007 were evaluated from prospectively maintained CRC and IBD databases. Clinical presentation, tumor stage, presence of associated dysplasia, and short- and long-term outcomes after surgery were investigated. Outcomes for IBD patients were compared with a matched group of patients with sporadic cancer.

RESULTS

A total of 240 IBD patients (64 CD and 176 UC) with CRC were identified. At the time of CRC diagnosis, 68% UC and 26% CD patients had pancolitis. About 92% of the patients who underwent preoperative colonoscopy were noted to have suspicious lesions. Although 92.5% of the patients had a preoperative histopathologic diagnosis of cancer or dysplasia, incidental diagnosis of cancer in the resection specimen was made in 3%. Examination of the resection specimen revealed synchronous dysplasia in 48% of the patients and synchronous cancer in 12% patients. Tumor location was rectum in 36%, right colon in 28%, sigmoid colon in 17%, transverse colon 10%, and left colon in 9% of patients. CD patients were diagnosed at a more advanced cancer stage than UC. Local recurrence and overall 5-year survival rates were comparable (5.6% vs. 6.7%, P = 0.78 and 77% vs. 72%, P = 0.5, respectively) for patients with IBD and sporadic cancer.

CONCLUSIONS

Most IBD cancer can be diagnosed or suspected on the basis of endoscopic findings, biopsy of areas of active colitis, and an incidental finding of malignancy after colorectal resection for other indications is rare. CD patients present with a more advanced cancer stage. Optimal endoscopic surveillance may identify most patients with IBD cancer.

Colorectal dysplasia in chronic inflammatory bowel disease: pathology, clinical implications, and pathogenesis

CONTEXT

Colorectal cancer, the most lethal long-term complication of chronic inflammatory bowel disease (IBD), is the culmination of a complex sequence of molecular and histologic derangements of the intestinal epithelium that are initiated and at least partially sustained by chronic inflammation. Dysplasia, the earliest histologic manifestation of this process, plays an important role in cancer prevention by providing the first clinical alert that this sequence is underway and serving as an endpoint in colonoscopic surveillance of patients at high risk for colorectal cancer.

OBJECTIVE

To review the histology, nomenclature, clinical implications, and molecular pathogenesis of dysplasia in IBD.

DATA SOURCE

Literature review and illustrations from case material.

CONCLUSIONS

The diagnosis and grading of dysplasia in endoscopic surveillance biopsies play a decisive role in the management of patients with IBD. Although interpathologist variation, endoscopic sampling problems, and incomplete information regarding the natural history of dysplastic lesions are important limiting factors, indirect evidence that surveillance may be an effective means of reducing cancer-related mortality in the population with IBD has helped validate the histologic criteria, nomenclature, and clinical recommendations that are the basis of current practice among pathologists and clinicians. Emerging technologic advances in endoscopy may permit more effective surveillance, but ultimately the greatest promise for cancer prevention in IBD lies in expanding our thus far limited understanding of the molecular pathogenetic relationships between neoplasia and chronic inflammation.

Colorectal carcinoma and preceding fistula in Crohn's disease

BACKGROUND

An increased risk for intestinal carcinoma is known in Crohn's disease, but there are also several reports on patients with perianal fistula and later carcinoma at this location - so to call fistula associated carcinoma.

METHODS

We retrospectively investigated 591 patients with CD who underwent abdominal surgery during the last 10 years (1997-2006) and found seven patients (5 male, 2 female, median age: 53 years (range 37-74)) with colorectal cancer (Dukes A-C), four of them (57%) with fistula associated CRC. These seven patients with CRC were matched 1:3 to randomly selected Crohn's patients based on age. The medical records of these 21 patients (11 with perianal fistula (52%)) were evaluated with respect to duration and pattern of intestinal involvement of CD, fistula history, intestinal surgery, perianal surgery, prior immunosuppressive and 5-ASA derivative intake.

RESULTS

Colorectal cancer was significantly (p=0.048) associated with longstanding anorectal fistula (median=11 years (range 0-28 years)) in the CRC group compared to the matched Crohn's patients (median=1 year (range 0-6 years)). Earlier colonic surgery seemed to protect from later malignancy (p=0.036). No significant symptoms preceded rectal carcinoma, except for new blood drainage from fistula in 2 patients. Two patients underwent ileocolonoscopy within 1 year before the diagnosis of malignancy and 2 patients underwent MRI of the pelvic region within 4 months.

CONCLUSION

Colorectal carcinoma is frequently associated with the presence of longstanding anorectal fistula.

Inflammatory bowel disease and intestinal cancer: a paradigm of the Yin-Yang interplay between inflammation and cancer

Colon cancer represents a paradigm for the connection between inflammation and cancer in terms of epidemiology and mechanistic studies in preclinical models. Key components of cancer promoting inflammation include master transcription factors (for example, nuclear factor kappaB, STAT3), proinflammatory cytokines (for example, tumor necrosis factor, interleukin-6 (IL-6)), cyclooxygenase-2 and selected chemokines (for example, CCL2). Of no less importance are mediators that keep inflammation in check, including IL-10, transforming growth factorbeta, toll-like receptor and the IL-1 receptor inhibitor TIR8/SIGIRR, and the chemokine decoy and scavenger receptor D6. Dissection of molecular pathways involved in colitis-associated cancer may offer opportunities for innovative therapeutic strategies.