Microsatellite instability is associated with reduced disease specific survival in stage III colon cancer.

BACKGROUND: Up to 15% of colorectal cancers exhibit microsatellite instability (MSI), where errors in replication go unchecked due to defects in the mismatch repair system. This study aimed to determine survival in a large single-centre series of 1250 consecutive colorectal cancers subjected to universal MSI testing. METHODS: Clinical and pathological features of patients with colorectal cancer identified on prospectively maintained colorectal and pathology databases at St. Vincent's University Hospital from 2004 to May 2012 were examined. Mismatch repair (MMR) status was determined by immunohistochemistry. Kaplan-Meier curves, the log-rank test and Cox regression were used to associate survival with clinical and pathological characteristics. RESULTS: Of the 1250 colorectal cancers in the study period, 11% exhibited MSI (n = 138). Patients with MSI tumours had significantly lower rates of lymph node and distant metastases (MSI N+ rate: 24.8% compared with MSS N+ rate: 46.2%, p < 0.001). For Stage I and II disease MSI was associated with improved disease free survival (DSS) compared with MSS colon cancer. However, patients with Stage III MSI colon cancers had a worse DSS than those with MSS tumours. Stage III MSI tumours exhibited higher rates of lymphovascular invasion and perineural invasion than Stage I/II MSI tumours. CONCLUSION: MSI is associated with a reduced risk of nodal and distant metastases, with an improved DSS in Stage I/II colon cancer. However, when MSI tumours progress to Stage III these patients had worse outcomes and pathological features. New strategies for this cohort of patients may be required to improve outcomes.

Incidence, care quality and outcomes of patients with acute kidney injury in admitted hospital care.

BACKGROUND/INTRODUCTION: Acute kidney injury (AKI) is common in acute hospital admission and associated with worse patient outcomes. AIM: To measure incidence, care quality and outcome of AKI in admitted hospital care. DESIGN: Forty-six of 168 acute NHS healthcare trusts in UK caring for 2 million acute hospital admissions per annum collected information on adults identified with AKI stage 3 (3-fold rise in serum creatinine or creatinine >354 µmol/l) through routine biochemical testing over a 5-month period in 2012. METHODS: Information was collected on patient and care characteristics. Primary outcomes were survival and recovery of kidney function at 1 month. RESULTS: A total of 15 647 patients were identified with biochemical AKI stage 3. Case note reviews were available for 7726 patients. In 80%, biochemical AKI stage 3 was confirmed clinically. Among this group, median age was 75 years, median length of stay was 12 days and the overall mortality within 1 month was 38%. Significant factors in a multivariable model predicting survival included age and some causes of AKI. Dipstick urinalysis, medication review, discussion with a nephrologist and acceptance for transfer to a renal unit were also associated with higher survival, but not early review by a senior doctor, acceptance for transfer to critical care or requirement for renal replacement therapy. Eighteen percent of people did not have their kidney function checked 1 month after the episode had resolved. DISCUSSION/CONCLUSIONS: This large study of in-hospital AKI supports the efficacy of biochemical detection of AKI in common usage. AKI mortality remains substantial, length of stay comparable with single-centre studies, and much of the variation is poorly explained (model Cox and Snell R2 = 0.131) from current predictors.

Spatial variation of the colonic microbiota in patients with ulcerative colitis and control volunteers.

OBJECTIVES: The relevance of spatial composition in the microbial changes associated with UC is unclear. We coupled luminal brush samples, mucosal biopsies and laser capture microdissection with deep sequencing of the gut microbiota to develop an integrated spatial assessment of the microbial community in controls and UC. DESIGN: A total of 98 samples were sequenced to a mean depth of 31,642 reads from nine individuals, four control volunteers undergoing routine colonoscopy and five patients undergoing surgical colectomy for medically-refractory UC. Samples were retrieved at four colorectal locations, incorporating the luminal microbiota, mucus gel layer and whole mucosal biopsies. RESULTS: Interpersonal variability accounted for approximately half of the total variance. Surprisingly, within individuals, asymmetric Eigenvector map analysis demonstrated differentiation between the luminal and mucus gel microbiota, in both controls and UC, with no differentiation between colorectal regions. At a taxonomic level, differentiation was evident between both cohorts, as well as between the luminal and mucosal compartments, with a small group of taxa uniquely discriminating the luminal and mucosal microbiota in colitis. There was no correlation between regional inflammation and a breakdown in this spatial differentiation or bacterial diversity. CONCLUSIONS: Our study demonstrates a conserved spatial structure to the colonic microbiota, differentiating the luminal and mucosal communities, within the context of marked interpersonal variability. While elements of this structure overlap between UC and control volunteers, there are differences between the two groups, both in terms of the overall taxonomic composition and how spatial structure is ascribable to distinct taxa.

Tumour microenvironment of both early- and late-stage colorectal cancer is equally immunosuppressive.

BACKGROUND: Tumour microenvironment (TME) of advanced colorectal cancer (CRC) suppresses dendritic cell (DC) maturation. Here, our aim was to determine how the microenvironment of early-stage tumours influences DCs. METHODS: Tumour-conditioned media (TCM) was generated by culturing explant tumour tissue in vitro (n=50). Monocyte-derived DCs (MDDCs) of healthy donors or cancer patients were pretreated with TCM and stimulated with lipopolysaccharide (LPS). DC maturation was assessed by flow cytometry and cytokine production measured by ELISA. RESULTS: TCM from both early- and late-staged tumours abrogated LPS-induction of IL-12p70 secretion, while increasing IL-10. The profile of inflammatory mediators in TCM was similar across stages, and all increased pSTAT3 expression by DCs.CRC patient DCs (n=31) secreted low levels of IL-12p70 and failed to upregulate expression of maturation markers in response to LPS. Furthermore, in vitro culture of autologous DCs with TCM did not change the hypo-responsiveness of patient DCs. CONCLUSION: Our data demonstrates that the TME of all stages of CRC contains inflammatory mediators capable of suppressing local DCs. MDDCs obtained from CRC patients are hyporesponsive to stimuli such as LPS. Measures to reverse the negative influence of the TME on DCs will optimise cancer vaccines in both early- and late-stage CRC.

Management of colorectal cancer in patients with inflammatory bowel disease.

BACKGROUND: This study evaluated the clinicopathological features and survival rates of patients with inflammatory bowel disease who developed colorectal cancer (CRC). METHODS: A retrospective review was performed on a prospectively maintained institutional database (1981-2011) to identify patients with inflammatory bowel disease who developed CRC. Clinicopathological parameters, management and outcomes were analysed. RESULTS: A total of 2,843 patients with inflammatory bowel disease were identified. One thousand six hundred and forty-two had ulcerative colitis (UC) and 1,201 had Crohn's disease (CD). Following exclusion criteria, there were 29 patients with biopsy-proven colorectal carcinoma, 22 of whom had UC and 7 had CD. Twenty-six patients had a preoperative diagnosis of malignancy/dysplasia; 16 of these were diagnosed at surveillance endoscopy. Nodal/distant metastasis was identified at presentation in 47 and 71 % of the UC and CD group, respectively. Operative morbidity for UC and CD was 33 and 17 %, respectively. Despite the less favourable operative outcomes following surgery management of UC-related CRC, overall 5-year survival was significantly better in the UC group compared to the CD group (41 vs. 29 %; p = 0.04) reflecting the difference in stage at presentation between the two groups. CONCLUSIONS: Patients who undergo surgery for UC-related CRC have less favourable short-term outcomes but present at a less advanced stage and have a more favourable long-term prognosis than similar patients with CRC and CD.

Associations of baseline characteristics with evolution of eGFR in a referred chronic kidney disease cohort.

BACKGROUND: Currently, most chronic kidney disease (CKD) classifications identify patients at different stages of CKD but do not identify risk of progression or adverse outcome. This analysis aims to describe associations between baseline characteristics and the evolution of estimated glomerular filtration rate (eGFR) and identify threshold values for clinical parameters that maximally discriminate progression to renal replacement therapy (RRT) in a referred cohort of patients with CKD stages 3-5. DESIGN AND METHODS: A longitudinal mixed-effect model was used to determine annualized estimated change in eGFR and classification tree analysis to identify threshold values that maximally discriminate progression to RRT. RESULTS: A total of 1316 patients were available for analysis with median follow-up of 33 months (interquartile range 20-60). Mixed model analysis suggested that the underlying diagnoses of autosomal dominant polycystic kidney disease and diabetic nephropathy exhibited on average a 2.7 (0.3) and 0.7 (0.3) ml/min/year faster rate of decline in eGFR, respectively, compared to those patients with biopsy-proven glomerulonephritis. In the regression tree analysis, we attempted to identify threshold values for clinical parameters that maximally discriminate progression to RRT. eGFR ≤24 ml/min was the first ranked discriminator, diastolic blood pressure appeared in the second and fourth rounds, eGFR appeared again in the third round together with cholesterol and systolic blood pressure, with basal metabolic index in the fourth. CONCLUSION: This analysis highlights risk factors for progressive kidney disease and demonstrates the variability in evolution of eGFR across the cohort as well as the importance of underlying renal disease type on the progression of CKD.

Hereditary mixed polyposis syndrome due to a BMPR1A mutation.

The conditions Juvenile Polyposis Syndrome (JPS) and Hereditary Mixed Polyposis Syndrome (HMPS) are associated with an increased risk of colorectal carcinoma. The genetic mechanisms which explain these conditions have until recently been poorly understood. Recent interest has focused on the transforming growth factor (TGF)-beta signalling pathway and, in particular, on mutations in the SMAD4 gene. However, not all cases of JPS and HMPS have mutations in SMAD4 and focus has now shifted to other components of the TGF-beta pathway to clarify the genetic mechanisms involved in these conditions. In this report, we describe the significance of a bone morphogenetic protein receptor type 1A gene mutation in an Irish family.

Nuclear oxidative damage correlates with poor survival in colorectal cancer.

Oxidative DNA damage results from DNA adducts such as 8-oxo-7, 8 dihydro-2'-deoxyguanosine (8-oxo-dG), which is a pro-mutagenic lesion. No known association between 8-oxo-dG, disease progression and survival exists in colorectal cancer (CRC). We examined levels of 8-oxo-dG in sporadic CRC to determine its relationship with pathological stage and outcome. A total of 143 CRC patients and 105 non-cancer patients were studied. Nuclear and cytoplasmic 8-oxo-dG was assessed using immunohistochemistry. Double immunofluorescence using 8-oxo-dG and manganese superoxide dismutase (MnSOD) antibodies localised cytoplasmic 8-oxo-dG. Apoptosis was detected using TUNEL. Nuclear staining levels were similar in tumour tissue and matched normal mucosa in both epithelial (P=0.22) and stromal (P=0.85) cells. Epithelial cytoplasmic staining was greater in tumour tissue (P<0.001). Double immunofluorescence localised cytoplasmic 8-oxo-dG to mitochondria. Epithelial and stromal nuclear 8-oxo-dG decreased with local disease spread, but highest levels were found in distant disease (P<0.01). Survival was related to epithelial nuclear and stromal staining in normal mucosa (P<0.001) and tumour (P<0.01) but was unrelated to cytoplasmic staining. Normal control cells in tissue from cancer patients with high levels of 8-oxo-dG failed to undergo cell death. 8-oxo-dG may be an important biomarker of disease risk, progression and survival for CRC patients.

Investigation of molecular markers in the diagnosis of refractory coeliac disease in a large patient cohort.

AIMS: Some patients with coeliac disease, despite strict adherence to a gluten-free diet, continue to have significant symptoms and/or a severe small intestinal histological lesion. The term "refractory coeliac disease" (rCD) is used to describe this condition. The purpose of this study was to investigate the value of tissue molecular markers reported to help in the diagnosis of rCD. METHODS: Details on 61 patients with suspected rCD were collected. The clinical and laboratory findings in these patients were carefully evaluated, in part to determine whether patients were adhering to a strict gluten-free diet. The co-expression of CD3 and CD8 on intraepithelial lymphocytes was investigated by monoclonal antibody staining of small intestinal biopsy tissue; a finding of less than 50% CD3+ cells co-expressing CD8 was defined as an aberrant phenotype. T cell receptor gene rearrangement was assessed when a sufficient tissue sample was available. RESULTS: A diagnosis of rCD was made in 38 patients based on clinical, laboratory and histological data. An aberrant intraepithelial lymphocyte population was found in 20 of these patients and in this group a clonal T cell population was found in five of seven patients tested. In the remaining 18 patients, the CD3/CD8 ratio was normal and two of seven tested had a clonal T cell population. After detailed monitoring, a diagnosis of rCD was excluded in the remaining 23 patients. CONCLUSIONS: This study supports the use of phenotypic and T cell clonality investigations in identifying patients with true rCD.

Bradykinin regulates human colonic ion transport in vitro.

BACKGROUND AND PURPOSE: Kinins are acknowledged as important regulators of intestinal function during inflammation; however, their effects on human intestinal ion transport have not been reported. Here, we used muscle-stripped human colonic tissue and cultured T(84)-cell monolayers to study bradykinin (BK) actions on human intestinal ion transport. EXPERIMENTAL APPROACH: Ion transport was measured as changes in short-circuit current (I(sc)) across colonic epithelia mounted in Ussing chambers. KEY RESULTS: In intact tissue, there was a distinct polarity to BK-elicited I(sc) responses. Whereas basolateral BK stimulated sustained responses (EC(50)=0.5+/-0.1 microM), those to apical BK were more rapid and transient (EC(50)=4.1+/-1.2 nM). In T(84) cells, responses to both apical and basolateral BK were similar to those seen upon apical addition to intact tissues. Cross-desensitization between apical and basolateral domains was not observed. BK-induced responses were largely due to Cl(-) secretion as shown by their sensitivity to bumetanide and removal of Cl(-) from the bathing solution. Studies using selective agonists and antagonists indicate responses to BK are mediated by B(2) receptors. Finally, responses to basolateral BK in intact tissues were inhibited by tetrodotoxin (1 microM), atropine (1 microM), capsaicin (100 microM) and piroxicam (10 microM). BK-stimulated prostaglandin (PG)E(2) release from colonic tissue. CONCLUSIONS: BK stimulates human colonic Cl(-) secretion by activation of apical and basolateral B(2) receptors. Responses to apical BK reflect a direct action on epithelial cells, whereas those to basolateral BK are amplified by stimulation of enteric nerves and PG synthesis.

Chronic kidney disease management in the United Kingdom: NEOERICA project results.

Early identification of patients with chronic kidney disease (CKD) may allow health-care systems to implement interventions aimed at decreasing disease progression and eventual morbidity and mortality. Primary care in the United Kingdom is computerized suggesting a separate screening program for CKD may not be necessary because identifying data already populates primary care databases. Our study utilized a data set of 163 demographic, laboratory, diagnosis, and prescription variables from 130 226 adults in the regions of Kent, Manchester, and Surrey. The patients were 18 years of age and older in a 5-year study period culminating in November 2003. Estimated glomerular filtration rate was calculated from the four-variable Modification of Diet in Renal Disease equation using calibrated creatinine levels. A valid creatinine value was recorded in almost 30% of this cohort. The age-standardized prevalence of stage 3-5 CKD was 10.6% for females and 5.8% for males. In these patients, the odds ratio for hypertension was 2.1, for diabetes 1.33, and for cardiovascular disease 1.69. Only 20% of the diabetic people with stage 3-5 CKD had a blood pressure less than or equal to 130/80 mm Hg. The proportion of patients with anemia significantly rose as renal function declined. We suggest that stage 3-5 CKD is easily detected in existing computerized records. The associated comorbidity and management is readily available enabling intervention and targeting of specialist resources.

Infliximab therapy in Crohn's disease: a pragmatic approach?

BACKGROUND: Infliximab is recognized as an effective therapy in unresponsive luminal and fistulating Crohn's disease. The use of maintenance or 'on demand' therapy thereafter is controversial. AIM: To assess the need for maintenance infliximab therapy in a clinical setting where immunomodulatory agents are widely used and where episodic therapy is used in preference to maintenance therapy. METHODS: Ninety-three patients with Crohn's disease receiving infliximab; 72 with unresponsive luminal disease and 21 with fistulous disease. Data collected included disease site and duration, surgical and smoking history, initial response rates, duration of response maintenance and concomitant medications. RESULTS: Fifty-six of 72 (78%) patients with luminal disease and 11 of 21 (52%) with fistulous disease achieved an initial response. Ten of 67 responders required conversion to maintenance infliximab infusions, while 31 remain in remission. Patients with luminal disease and those who had not taken previous surgery had higher response rates to infliximab. Younger patients and those with small bowel disease had higher relapse rates following initial response. Three patients developed allergic reactions to infliximab and one patient died of progressive pulmonary disease 6 weeks after their first infusion. CONCLUSIONS: Many patients with Crohn's disease can be maintained successfully with an episodic infliximab regimen.

Functional categories of TP53 mutation in colorectal cancer: results of an International Collaborative Study.

BACKGROUND: Loss of TP53 function through gene mutation is a critical event in the development and progression of many tumour types including colorectal cancer (CRC). In vitro studies have found considerable heterogeneity amongst different TP53 mutants in terms of their transactivating abilities. The aim of this work was to evaluate whether TP53 mutations classified as functionally inactive (< or=20% of wildtype transactivation ability) had different prognostic and predictive values in CRC compared with mutations that retained significant activity. MATERIALS AND METHODS: TP53 mutations within a large, international database of CRC (n = 3583) were classified according to functional status for transactivation. RESULTS: Inactive TP53 mutations were found in 29% of all CRCs and were more frequent in rectal (32%) than proximal colon (22%) tumours (P < 0.001). Higher frequencies of inactive TP53 mutations were also seen in advanced stage tumours (P = 0.0003) and in tumours with the poor prognostic features of vascular (P = 0.006) and lymphatic invasion (P = 0.002). Inactive TP53 mutations were associated with significantly worse outcome only in patients with Dukes' stage D tumours (RR = 1.71, 95%CI 1.25-2.33, P < 0.001). Patients with Dukes' C stage tumours appeared to gain a survival benefit from 5-fluorouracil-based chemotherapy regardless of TP53 functional status for transactivation ability. CONCLUSIONS: Mutations that inactivate the transactivational ability of TP53 are more frequent in advanced CRC and are associated with worse prognosis in this stage of disease.

Pathological response following long-course neoadjuvant chemoradiotherapy for locally advanced rectal cancer.

AIMS: To standardize the pathological analysis of total mesorectal excision specimens of rectal cancer following neoadjuvant chemoradiotherapy for locally advanced disease (T3/T4), including tumour regression. METHODS AND RESULTS: Standardized dissection and reporting was used for 60 patients who underwent total mesorectal excision following long-course chemoradiotherapy. Tumour regression was scored by two pathologists (K.S., D.G.) using both an established 5-point tumour regression grade (TRG), and a novel 3-point grade. Both scores were evaluated for interobserver variability. A complete or near-complete pathological response (3-point TRG 1) was found in 10 patients (17%). Using the 5-point TRG, there was good agreement between both pathologists (kappa = 0.64). Using the 3-point grade, agreement was excellent (kappa = 0.84). No disease recurrence has been reported in patients with a complete, or near complete pathological response (3-point TRG 1), after a mean follow-up of 22 months. CONCLUSION: Tumour regression grade is a useful method of scoring tumour response to chemoradiotherapy in rectal cancer. TRG 1 and 2 can be regarded as a complete pathological response (ypT0). A modified 3-point grade has the advantage of better reproducibility, with similar prognostic significance.

Diagnosis and treatment of enterovesical fistulae.

OBJECTIVE: Enterovesical fistulae are a recognized complication of a variety of inflammatory and neoplastic conditions. Despite advances in imaging and treatment the diagnosis may be delayed and the management remains diverse. We describe our experience with their diagnosis and management. PATIENTS AND METHODS: This retrospective study encompassed all patients referred over a 10-year period with clinical suspicion of or confirmed enterovesical fistula. Demographics, clinical presentation, aetiology and clinical outcome were evaluated. Mean follow-up was 18 months (range 6-50 months). RESULTS: Thirty patients were studied. The mean age was 63.5 years (range 23-92 years). Fifteen (50%) patients presented with classical urinary symptoms (pneumaturia, faecaluria and recurrent urinary tract infections). The commonest investigations (n, % positive) included CT (15, 80), cystoscopy (16, 87.5), endoscopy (11, 54.5) and barium enema (8, 50). There were 20 inflammatory and 10 neoplastic aetiologies. Five patients were treated conservatively and 25 patients underwent surgery. Surgery resulted in symptomatic cure in the majority of cases (22/25). CONCLUSION: Classical urinary symptoms were only evident in 50% of patients with confirmed fistulae. We advocate CT scanning as the optimum imaging modality before surgical intervention. Surgical treatment in a specialized unit remains the most effective treatment of enterovesical fistulae.

Expression of Cathepsin B and L antigen and activity is associated with early colorectal cancer progression.

Cathepsin B and Cathepsin L are cysteine proteases important in the process of invasion and metastasis. The aim of our study was to assay antigen and activity levels of these enzymes and to correlate these with established clinical and pathological prognostic parameters including patient survival. 99 patients undergoing operations for colorectal cancer were included in this study. We quantitated cathepsin B and L levels in matched normal mucosa and cancer samples using an enzyme-linked immunosorbent assay (ELISA) and specific activity assays and expressed the results as tumour/normal ratios. Significant correlations were found between tumour/normal cathepsin B and L antigen and activity ratios. Cathepsin B and L tumour/normal activity ratios were greater than 1 in early stage disease and there were gradual reductions in cathepsin B (P = 0.02) and L (P = 0.03) activity ratios with advancing tumour stage. Survival of patients with potentially curative disease was inversely related to both cathepsin B (P = 0.007) and L (P = 0.001) activity ratio, in addition to cathepsin L antigen ratio (P = 0.008). Our findings suggest that cysteine proteases play an important role in colorectal cancer progression.

An evaluation of left sided colonic polyps as a marker for right sided cancers.

The detection of a left-sided polyp on flexible sigmoidoscopy has been suggested as providing a heralding sign for right-sided tumours. We assessed our own experience with right-sided colonic cancers with reference to detection modality, surgical intervention and their association with left-sided polyps. We performed a retrospective review of a prospectively collected colorectal cancer database, with endoscopic and radiological records. Patients were subcategorised on the basis of the presence or absence of left-side polyps. Ninety-one consecutive patients who underwent curative surgery for right-sided colonic cancers were studied. Endoscopy was used to detect right-sided carcinomas in 10 (83%) of the 12 cases with synchronous left-sided polyps and radiological imaging utilised in 2 cases. In patients without evidence of left sided disease endoscopy was used in 40 (51%) of the 79 patients. In our experience most right sided cancers do not have a synchronous polyp evident on the left side 79 (87%).

Identification of benzene metabolites in dermal fibroblasts as nonphenolic: regulation of cell viability, apoptosis, lipid peroxidation and expression of matrix metalloproteinase 1 and elastin by benzene metabolites.

The skin is exposed to benzene and its derivatives, prevalent environmental chemicals. They may impair the structural integrity of the skin by increased expression of matrix metalloproteinase 1 (MMP-1; degrades structural collagen) and elastin, synthesized primarily by the dermal fibroblasts. We examined the metabolism of benzene in dermal fibroblasts and identified the benzene metabolites as toluene, benzaldehyde, aniline and benzoic acid. These metabolites were not toxic to the cells with regard to cell viability, apoptosis and lipid peroxidation, unlike the phenolic benzene metabolites (hydroquinone, t-butyl hydroquinone and phenol) or hydrogen peroxide. Toluene and phenol, which compose cigarette smoke, and benzaldehyde stimulated MMP-1 and/or elastin expression. In summary, the dermal fibroblasts metabolize benzene to nonphenolic metabolites that are less toxic to the cellular components than the phenolic benzene derivatives. Toluene, benzaldehyde and phenol can directly cause facial wrinkling and impaired structural integrity by upregulating MMP-1 and/or elastin.