Colibactin mutational signatures in NTHL1 tumor syndrome and MUTYH associated polyposis patients.

Polyketide synthase (pks) island harboring Escherichia coli are, under the right circumstances, able to produce the genotoxin colibactin. Colibactin is a risk factor for the development of colorectal cancer and associated with mutational signatures SBS88 and ID18. This study explores colibactin-associated mutational signatures in biallelic NTHL1 and MUTYH patients. Targeted Next Generation Sequencing (NGS) was performed on colorectal adenomas and carcinomas of one biallelic NTHL and 12 biallelic MUTYH patients. Additional fecal metagenomics and genome sequencing followed by mutational signature analysis was conducted for the NTHL1 patient. Targeted NGS of the NTHL1 patient showed somatic APC variants fitting SBS88 which was confirmed using WGS. Furthermore, fecal metagenomics revealed pks genes. Also, in 1 out of 11 MUTYH patient a somatic variant was detected fitting SBS88. This report shows that colibactin may influence development of colorectal neoplasms in predisposed patients.

Safety of endoscopic mucosal resection (EMR) of large non-pedunculated colorectal adenomas in the elderly.

BACKGROUND: Endoscopic mucosal resection (EMR) has been proven to be safe and effective for the treatment of colorectal adenomas. However, data are limited on the safety of this technique for large polyps and in elderly patients. Aims of our study were to examine the bleeding and perforation rates in patients with large non-pedunculated adenomas (≥20mm) and to evaluate the influence of size (≥40mm) and age (≥75 years) on the complication rates. METHODS: In this multicenter retrospective study, patients who underwent EMR of non-pedunculated adenomas ≥20mm between January 2012 and March 2016 were included. The demographics of the patients, the use of antithrombotic drugs, size of the polyps, type of resection, pathology report, occurrence of post-polypectomy bleeding, and perforation- and recurrence rate were collected. RESULTS: In 343 patients, 412 adenomas were removed. Eighty patients (23.3%) were ≥75 years of age, 138 polyps (33.5%) were ≥40mm. Bleeding complications were observed in 28 cases (6.8%) and were found significantly more frequent in adenomas ≥40mm, independent of the use of antithrombotic therapy. Five perforations (1.2%) were described, not related to the size of the polyp. There was no significant difference in complication rates between patients <75 years and patients ≥75 years. Bleeding complications rates were significantly higher in patients receiving double antithrombotic therapy. CONCLUSION: EMR is safe in elderly patients. EMR of adenomas of ≥40mm was associated with more bleeding complications. Future studies should address how the bleeding rates can be reduced in these patients, especially in those who use double antithrombotic treatment.

Biobanking of fresh-frozen endoscopic biopsy specimens from esophageal adenocarcinoma.

The process of preparing endoscopic esophageal adenocarcinoma samples for next-generation DNA/RNA sequencing is poorly described. Therefore, we assessed the feasibility and pitfalls of preparing esophageal adenocarcinoma endoscopic biopsies toward DNA/RNA samples suitable for next-generation sequencing. In this prospective study, four tumor biopsy samples were collected from consecutive esophageal cancer patients during esophagogastroduodenoscopy and fresh-frozen in liquid nitrogen. DNA and RNA were isolated from samples with a tumor percentage of at least 50%. For next-generation sequencing, double-stranded DNA (dsDNA) is required and high-quality RNA preferred. The quantity dsDNA and RNA quantity and quality were assessed with the Nanodrop 2000 spectrophotometer (Thermo Fisher Scientific, Waltham, MA, USA) and Agilent 2100 Bioanalyzer (Agilent, Santa Clara, CA, USA). Biopsy samples of 69 consecutive patients with esophageal adenocarcinoma were included. In five patients (7%), the tumor percentage was less than 50% in all four biopsies. Using a protocol allowing simultaneous DNA and RNA isolation, the median dsDNA yield was 2.4 µg (range 0.1-12.0 µg) and the median RNA yield was 0.5 µg (range 0.01-2.05 µg). The median RNA integrity number of samples that were fresh-frozen within 30 minutes after sampling was 6.7 (range 4.2-8.9) compared with 2.5 (1.8-4.5) for samples that were fresh-frozen after 2 hours. The results from this study show that obtaining dsDNA and RNA for next-generation sequencing from endoscopic esophageal adenocarcinoma samples is feasible. Tumor percentage and dsDNA/RNA yield and quality emphasize the need for sampling multiple biopsies and minimizing the delay before fresh-freezing.

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.

MMP-2 and MMP-9 in normal mucosa are independently associated with outcome of colorectal cancer patients.

BACKGROUND: Upregulation of the matrix metalloproteinases MMP-2 and MMP-9 in various cancers has been associated with worse survival of the patients. METHODS: We assessed MMP-2 and MMP-9 levels in normal colorectal mucosa from colorectal cancer patients in relation to the course of the disease. RESULTS: A high protein expression of MMP-2 as well as MMP-9 in normal mucosa was found to be correlated with worse 5-year survival. The combination of both parameters was an even stronger prognostic factor. These protein levels were found not to be related to the corresponding single nucleotide polymorphisms of MMP-2 (-1306C>T) and MMP-9 (-1562C>T). Multivariate analyses indicated that the MMP-2 and MMP-9 levels in normal mucosa are prognostic for survival, independent of TNM classification. CONCLUSION: MMP-2 and MMP-9 levels in normal mucosa are indicative of the course of disease in colorectal cancer patients.

Evaluation of management of desmoid tumours associated with familial adenomatous polyposis in Dutch patients.

BACKGROUND: The optimal treatment of desmoid tumours is controversial. We evaluated desmoid management in Dutch familial adenomatous polyposis (FAP) patients. METHODS: Seventy-eight FAP patients with desmoids were identified from the Dutch Polyposis Registry. Data on desmoid morphology, management, and outcome were analysed retrospectively. Progression-free survival (PFS) rates and final outcome were compared for surgical vs non-surgical treatment, for intra-abdominal and extra-abdominal desmoids separately. Also, pharmacological treatment was evaluated for all desmoids. RESULTS: Median follow-up was 8 years. For intra-abdominal desmoids (n=62), PFS rates at 10 years of follow-up were comparable after surgical and non-surgical treatment (33% and 49%, respectively, P=0.163). None of these desmoids could be removed entirely. Eventually, one fifth died from desmoid disease. Most extra-abdominal and abdominal wall desmoids were treated surgically with a PFS rate of 63% and no deaths from desmoid disease. Comparison between NSAID and anti-estrogen treatment showed comparable outcomes. Four of the 10 patients who received chemotherapy had stabilisation of tumour growth, all after doxorubicin combination therapy. CONCLUSION: For intra-abdominal desmoids, a conservative approach and surgery showed comparable outcomes. For extra-abdominal and abdominal wall desmoids, surgery seemed appropriate. Different pharmacological therapies showed comparable outcomes. If chemotherapy was given for progressively growing intra-abdominal desmoids, most favourable outcomes occurred after combinations including doxorubicin.

Double balloon endoscopy for detection of small-bowel adenomas in familial adenomatous polyposis after pancreaticoduodenectomy according to Whipple.

Patients with familial adenomatous polyposis (FAP) have a 5%-10% lifetime risk of developing duodenal cancer. In severe duodenal polyposis, pancreaticoduodenectomy according to Whipple has been considered the only way to cure duodenal polyposis. However, polyps recur even after surgery. We describe a patient with severe adenomatosis of the small bowel in the afferent loop of a Roux-en-Y anastomosis after a Whipple procedure, detected by double balloon endoscopy (DBE). This is the first description of the use of DBE for this indication, and emphasizes the need for surveillance of the small bowel after surgery, especially in the area of the biliary anastomosis.

MMP-2 geno-phenotype is prognostic for colorectal cancer survival, whereas MMP-9 is not.

The prognostic significance of single-nucleotide polymorphisms (SNPs) and tumour protein levels of MMP-2 and MMP-9 was evaluated in 215 colorectal cancer patients. Single-nucleotide polymorphism MMP-2(-1306T) and high MMP-2 levels were significantly associated with worse survival. Extreme tumour MMP-9 levels were associated with poor prognosis but SNP MMP-9(-1562C>T) was not. Tumour MMP levels were not determined by their SNP genotypes.

Thalidomide as treatment for digestive tract angiodysplasias.

An 80-year-old man with von Willebrand's disease was admitted with severe melaena. Despite suppletion with von Willebrand concentrate he continued to be dependent on blood transfusions. Endoscopic examination did not show a bleeding focus. Video capsule endoscopy showed active bleeding from angiodysplasias in the proximal section of the small intestine. Ultimately, treatment with thalidomide was initiated at a dose of 100 mg/day. Soon after starting treatment his stools became normal and his haemoglobin level stabilised. No bleeding problems occurred for 11 months, after which the thalidomide treatment was stopped because of the potential side effects. Two months later he again developed melaena and treatment with thalidomide was restarted with a successful outcome. Trying to lower the dose to 50 mg resulted in rebleeding after three months with stabilisation after increasing the dose to 100 mg again. Monotherapy with thalidomide improves the clinical picture but may not be sufficient in the long term. Additional therapy, such as argon plasma coagulation or the use of the novel drug lenalidomide, might be necessary.

[Pancreatitis ascribed to the use of itraconazole]. / Pancreatitis toegeschreven aan het gebruik van itraconazol.

A 50-year-old woman was treated intermittently with itraconazole (Trisporal) due to onychomycosis. After the initial period of 7 days and after the first 9 days of the second period she experienced abdominal complaints. In the second episode, pancreatitis was diagnosed. No known risk factors for acute pancreatitis were present. The pancreatitis may have arisen due to the use of itraconazole. As far as we know, this side effect of itraconazole or other triazole derivatives has not previously been reported in the literature. It seems to be a rare side effect, for which the pathogenesis has yet to be elucidated.

Morphometry of interstitial fibrosis.

Several clinical studies have confirmed that histomorphometric changes in the tubulointerstitial compartment contain the best correlating parameters to predict the development of progressive renal insufficiency. The process of interstitial fibrosis is accompanied by an influx of inflammatory cells, up-regulation of fibrogenic cytokines such as transforming growth factor-beta and basic fibroblast growth factor, transient down-modulation of their antagonists, generation and proliferation of myofibroblasts, and, finally, by accumulation of interstitial collagens and proteoglycans. A careful morphometric analysis of interstitial fibrosis requires sensitive parameters through which the severity can be quantified and by which the progression into renal insufficiency can be predicted. We have addressed these issues by morphometric analysis of both human biopsies and by refining existing experimental models in the rat. Morphometric analysis was performed using a Zeiss microscope equipped with a full colour 3CCD camera and KS-400 image analysis software from Zeiss-Kontron. For studies with human material, biopsies were examined from patients with various renal diseases including patients with chronic allotransplant dysfunction. The development of interstitial fibrosis was correlated with clinical parameters. In experimental models, we analysed the interstitial composition and eventual glomerular alterations in rats with bovine serum albumin (BSA)-induced protein overload nephropathy and with human IgG-induced chronic serum sickness nephritis. Finally, we adapted and refined the model of ureter obstruction-induced interstitial fibrosis in the rat. For this purpose, custom-made titanium clips (S&T, Neuhaus, Switzerland) were implanted around the ureter in the abdomen of rats to obstruct the ureter without causing necrosis. The clips were removed at various time points after obstruction of the ureter (1-14 days). The subsequent remodelling of the interstitium was studied thereafter, in order to establish whether uraemia-induced interstitial fibrosis remains reversible at all times. In rat models, we have found that both protein overload-induced and serum sickness-induced interstitial fibrosis are accompanied by the development of focal and segmental glomerulosclerosis. Only in the ureter obstruction model did selective interstitial fibrosis develop, and remained reversible at all times studied. For the reliable assessment of interstitial fibrosis we have found that the best correlating parameters of interstitial fibrosis with renal function were: (i) the ratio of protein accumulation of TGF-beta-1 and its antagonist decorin; (ii) interstitial expression of smooth muscle alpha-actin; and (iii) accumulation of interstitial collagens (as determined by immunoperoxidase and by Sirius red staining).

Role of tubular cells in progressive renal disease.

It is generally accepted that the progressive loss of kidney function results from a pathogenic process that is independent of the original etiology, functioning as a final common pathway. Part of this response is characterized by triggering of interstitial infiltration and induction of tubular damage. As a consequence, tubular epithelial cells (TEC) can become activated and begin to express several inflammatory mediators. In the present review, we will summarize the potential role of TEC in progressive renal disease. Much emphasis will be put on studies using in vitro cultured TEC. These studies have provided more insight into the different signals involved in the regulation of the production of inflammatory mediators like complement, cytokines and chemokines, as well as progression factors like growth factors and matrix component by TEC.