Reconstructing topography and extent of injury to the superior mesenteric artery plexus in right colectomy with extended D3 mesenterectomy: a composite multimodal 3-dimensional analysis.

BACKGROUND: Superior mesenteric artery plexus (SMAP) injury is reported to cause postoperative intractable diarrhea after pancreatic/colonic surgery with extended lymphadenectomy. This study aims to describe the SMAP microanatomy and extent of injury after right colectomy with extended D3 mesenterectomy for cancer. METHODS: Three groups (I) anatomical dissection, (II) postmortem histology, and (III) surgical specimen histology were included. Nerve count and area were compared between groups II and III and paravascular sheath thickness between groups I and II. 3D models were generated through 3D histology, nanoCT scanning, and finally through 3D printing. RESULTS: A total of 21 specimens were included as follows: Group (I): 5 (3 females, 80-93 years), the SMAP is a complex mesh surrounding the superior mesenteric artery (SMA), branching out, following peripheral arteries and intertwining between them, (II): 7 (5 females, 71-86 years), nerve count: 53 ± 12.42 (38-68), and area: 1.84 ± 0.50 mm2 (1.16-2.29), and (III): 9 (5 females, 55-69 years), nerve count: 31.6 ± 6.74 (range 23-43), and area: 0.889 ± 0.45 mm2 (range 0.479-1.668). SMAP transection injury is 59% of nerve count and 48% of nerve area at middle colic artery origin level. The median values of paravascular sheath thickness decreased caudally from 2.05 to 1.04 mm (anatomical dissection) and from 2.65 to 1.17 mm (postmortem histology). 3D histology models present nerve fibers exclusively within the paravascular sheath, and lymph nodes were observed only outside. NanoCT-derived models reveal oblique nerve fiber trajectories with inclinations between 35° and 55°. Two 3D-printed models of the SMAP were also achieved in a 1:2 scale. CONCLUSION: SMAP surrounds the SMA and branches within the paravascular sheath, while bowel lymph nodes and vessels lie outside. Extent of SMAP injury on histological slides (transection only) was 48% nerve area and 59% nerve count. The 35°-55° inclination range of SMAP nerves possibly imply an even larger injury when plexus excision is performed (lymphadenectomy). Reasons for later improvement of bowel function in these patients can lie in the interarterial nerve fibers between SMA branches.

Real-life chromoendoscopy for dysplasia surveillance in ulcerative colitis.

AIM: To evaluate the use of chromoendoscopy for surveillance of ulcerative colitis in a real-life community hospital setting. METHODS: Patients with extensive ulcerative colitis, having disease duration of more than 8 years and who presented between the years of 1999 to 2013, were offered enrolment in this single cohort prospective study. All participants underwent standard bowel preparation with sodium phosphate and chromoendoscopy. Two expert endoscopists, novice to chromoendoscopy, evaluated each segment of the colon with standard-definition colonoscopes after spray application of 0.4% indigo carmine. All observed lesions were recorded and evaluated before being removed and/or biopsied. In addition, nontargeted biopsies were taken from each segment of the colon. The dysplasia detection rate and dysplasia detection yield were ascertained. RESULTS: A total of 21 neoplastic lesions (2 carcinomas, 4 of high-grade dysplasia and 15 of low-grade dysplasia) and 27 nondysplastic lesions were detected in 16 of the total 67 patients (70% male; median disease duration: 17 years; median age at diagnosis: 25 years; 92% aminosalicylate-treated). The dysplasia detection rate was 10.5% (7/67 patients). The dysplasia detection yield was 20.8% (10/48) for targeted biopsies and 3.5% (11/318) for nontargeted biopsies. The sensitivity and specificity for the macroscopic evaluation of neoplasia using chromoendoscopy were 48% [95% confidence interval (CI): 26%-70%] and 96% (95%CI: 93%-98%), respectively. The positive predictive and negative predictive values were 42% (95%CI: 27%-59%) and 97% (95%CI: 95%-98%), respectively. A total of 19/21 dysplastic lesions were detected in mucosa with histologic inflammation. CONCLUSION: Chromoendoscopy seems to be of value for dysplasia surveillance of ulcerative colitis in a community hospital setting. The yield of non-targeted biopsies is negligible.

Multi-target stool DNA test in the surveillance of inflammatory bowel disease: a cross-sectional cohort study.

BACKGROUND AND AIM: Colonoscopic surveillance is recommended in patients with longstanding inflammatory bowel disease (IBD) as they are at increased risk of colorectal cancer (CRC). Non-invasive surveillance may improve compliance and access. Multi-target stool DNA (MT-sDNA) has been validated for screening of sporadic CRC but has not been assessed in IBD. Our aim was to assess the performance of a MT-sDNA test in a real-life surveillance setting of patients with longstanding IBD. MATERIAL AND METHODS: A total of 192 IBD patients enrolled from two prospective cohorts submitted an EDTA buffered stool sample and underwent chromo- or white light colonoscopy. Stools were assayed for methylated BMP3 & NDRG4, mutant KRAS and ß-actin by a laboratory blinded to clinical data. RESULTS: The multitarget-sDNA panel was positive in 2/2 CRC and 5/15 low-grade dysplasia (LGD) < 1 cm in diameter. Sensitivities were 100% (95% CI 16-100%) for CRC and 33% (95% CI 13-61%) for LGD lesions <1 cm, with specificities of 87% (95% CI 81-91%) and 93% (95% CI 88-96%), respectively. The estimated number of patients needed to screen to detect a single CRC was 96 (95% CI 93-99%) and was 28 (95% CI 22-34%) to detect any colorectal neoplasia (CRN). CONCLUSION: The MT-sDNA panel detected CRC in IBD. Sensitivity for sub-centimeter colorectal neoplasms in IBD patients appears similar to that observed in the general population. The test may be a valuable tool for detection of malignancy during structured surveillance of long-term IBD in a first line hospital setting.

Symptoms and Mucosal Changes Stable During Rapid Increase of Pediatric Celiac Disease in Norway.

OBJECTIVES: We aimed to study whether the incidence of pediatric celiac disease (CD) in South-Eastern Norway changed from 2000 to 2010. We also examined whether there was a change in symptoms and histopathological morphology in the duodenal biopsies during the same period. METHODS: In 3 hospitals in South-Eastern Norway, records from pediatric patients (0-14.9 years) diagnosed with CD during two 3-year periods (2000-2002 and 2008-2010) were reviewed. Only cases with a duodenal biopsy diagnosis of CD classified as Marsh grade 2 and 3a-c were included. Frequencies of symptoms, anthropometric data, and laboratory results were compared, in addition to re-examinations of histological sections from one of the hospitals. RESULTS: A total of 400 cases were diagnosed with a female to male ratio of 1.5:1. The incidence rate for 2000 to 2002 was 15.9 cases per 100,000 person-years (95% confidence interval 12.8-19.4), compared with 45.5 cases per 100,000 person-years during 2008 to 2010 (95% confidence interval 40.5-50.9), P < 0.001. The relative frequencies of symptoms and the distribution of histopathological changes were similar in the 2 periods, whereas weight z scores and hemoglobin levels were significantly lower in the first period. CONCLUSIONS: We found a 3-fold increase in the incidence rate for CD in the Norwegian pediatric population during the decade 2000 to 2010. Slightly higher weight and hemoglobin levels at diagnosis in the latter period may be due to improved CD awareness. Unaltered relative frequencies of symptoms and histopathological changes in the gut, however, suggest a true increase of CD in Norwegian children.

TP53/p53 alterations and Aurora A expression in progressor and non-progressor colectomies from patients with longstanding ulcerative colitis.

Aneuploidy is a common feature in the colonic mucosa of patients suffering from the inflammatory bowel disease ulcerative colitis (UC) and often precedes the development of dysplasia and cancer. Aneuploidy is assumed to be caused by missegregation of chromosomes during mitosis, often due to a faulty spindle assembly checkpoint. p53 is a tumour suppressor protein known to regulate the spindle assembly checkpoint and is frequently mutated in aneuploid cells. Aurora A is a presumed oncoprotein, also involved in regulation of the spindle assembly checkpoint. In the present study, we examined the mutational frequency of TP53 and the protein levels of p53 in a set of 20 progressor and 10 non-progressor colectomies from patients suffering from longstanding UC. In addition, we re-examined previously published immunohistochemical data on Aurora A expression using the same material. Levels of Aurora A were re-examined with regard to DNA ploidy status and dysplasia within the progressors, as well as in relation to p53 accumulation and TP53 mutational status. We detected p53 accumulation only within the progressor colectomies, where it could be followed back 14 years prior to the colectomies, in pre-colectomy biopsies. TP53 mutations were detected in both progressors and non-progressors. Expression levels of Aurora A were similar in the progressors and non-progressors. Within the group of progressors however, low levels of Aurora A were associated with areas of DNA aneuploidy, as well as with increasing degrees of dysplasia. Our results indicate that alterations in p53 may be an early biomarker of a progressor colon, and that p53 is accumulated early in UC-related carcinogenesis. Furthermore, a decreased Aurora A expression is associated with the development of DNA aneuploidy, as well as with dysplasia in UC progressors.

Reduced hTERT protein levels are associated with DNA aneuploidy in the colonic mucosa of patients suffering from longstanding ulcerative colitis.

Longstanding ulcerative colitis (UC) is a disease of chronic inflammation of the colon. It is associated with the development of colorectal cancer through a multistep process including increasing degrees of dysplasia and DNA-ploidy changes. However, not all UC patients will develop these characteristics even during lifelong disease, and patients may therefore be divided into progressors who develop dysplasia or cancer, and non-progressors who do not exhibit such changes. In the present study, the amount of hTERT, the catalytic subunit of the enzyme telomerase, was estimated by using peroxidase immunohistochemistry (IHC) in a set of progressor and non-progressor UC colectomies. The protein levels in the colonic mucosa of the progressors and non­progressors were compared, and further comparisons between different categories of dysplastic development and to DNA-ploidy status within the progressors were made. Levels of hTERT were elevated in the colonic mucosa of the progressors and non-progressors when compared to non-UC control samples, but no difference was observed between the hTERT levels in the mucosa of progressors and non-progressors. The levels of hTERT associated with levels of Ki67 to a significant degree within the non-progressors. hTERT expression in lesions with DNA-aneuploidy were decreased as compared to diploid lesions, when stratified for different classes of colonic morphology. Our results indicate an association between hTERT protein expression and aneuploidy in UC-progressor colons, and also a possible protective mechanism in the association between hTERT and Ki67, against development of malignant features within the mucosa of a UC-colon.

Evaluation of suitable reference genes for normalization of real-time reverse transcription PCR analysis in colon cancer.

BACKGROUND: Real-time reverse transcription PCR (qRT-PCR) is frequently used for gene expression quantification due to its methodological reproducibility and sensitivity. The gene expression is quantified by normalization to one or more reference genes which are presumed stably expressed throughout a given experiment. The aim of this study was to validate a standardized experimental setup to identifying reference genes for normalization of qRT-PCR in the metastatic and non-metastatic colon cancer. METHODS: In this study, expression of 16 commonly used reference genes was quantified in tumour tissue and individual-matched normal mucosa in 18 non-metastatic colon cancer patients and 20 colon cancer patients with distant metastases using TaqMan Low Density Array (TLDA). The expression stability was determined and compared by means of geNorm and NormFinder. RESULTS: Two pairs of genes, HPRT1/PPIA and IPO8/PPIA, were identified to be suitable to normalize gene expression data in metastatic and non-metastatic colon cancer patients, according to geNorm and NormFinder respectively. CONCLUSION: We propose a standardized approach of finding the most suitable reference gene(s) in every qRT-PCR experiment using TLDA.

Relationship between clinical parameters and the colitis-colorectal cancer interval in a cohort of patients with colorectal cancer in inflammatory bowel disease.

OBJECTIVE: Inflammatory bowel disease (IBD) is associated with an increased risk of colorectal cancer (CRC), but more knowledge is needed about the possible relationship between clinical parameters and the time to development of cancer in IBD. The aim of the study was to determine the variability of the colitis-CRC interval and to analyze the association with clinical variables in an attempt to gain information on predictive factors of time to cancer within a relatively large cohort of CRC patients. MATERIAL AND METHODS: Patients diagnosed with IBD prior to 1 May 2005 at three university hospitals in Oslo were matched against the CRC files at the Cancer Registry of Norway. Only histological re-confirmed IBD and adenocarcinoma of the colorectum were included. RESULTS: Sixty-one patients with CRC in ulcerative colitis and 6 in Crohn's disease, including 13 CRC in primary sclerosing cholangitis (PSC), covering a follow-up of 1625 patient years,were identified. The median time from diagnosis of IBD to CRC was 17 years. Seven of 58 patients (12%) developed CRC within 10 years from onset of IBD symptoms and 14/67 (21%) within 10 years after the diagnosis of IBD. The colitis-CRC interval decreased by a factor of 0.154 (p = 0.018) when age at onset of IBD increased by one year. Mean age at onset of IBD was 30 years in patients with Dukes' stage C or D compared with 20 years in Dukes' stage A or B patients (p = 0.017). The colitis-CRC interval decreased by a factor of 0.138 (p = 0.003) when the percentage of the colitis-CRC interval with active symptoms increased by 1%. Patients with PSC were significantly younger at onset of IBD symptoms (PSC: 19 years versus no PSC:29 years, p = 0.04), but the colitis-CRC interval was similar to IBD without PSC (17 years versus 20 years, p = 0.236). Mean duration of the colitis-CRC interval was not related to family history or drug consumption prior to CRC. CONCLUSIONS: In the present cohort, for whom the median time from diagnosis of IBD to CRC was 17 years, 21% of the cancers developed before 10 years of disease, which is before colonoscopic screening is usually recommended. High age at onset of IBD may be related to a more aggressive development of CRC in IBD and early inclusion in screening programs might be considered for this group of patients. Symptom activity but not the diagnosis of PSC, family history of CRC or IBD or drug treatment seems to have an effect on the colitis-CRC interval.