Introduction Carbonate formations generally have broad pore size distributions, from microcrystalline pores to large vugs. Understanding these pore spaces and their geometries is crucial to hydrocarbon reservoir characterization, and because carbonates form aquifers in many regions, an understanding of their pore systems is critical to an understanding of hydrological processes, as well.
Environmental factors, including westernised diets and alterations to the gut microbiota, are considered risk factors for inflammatory bowel diseases (IBD). The mechanisms underpinning diet-microbiota-host interactions are poorly understood in IBD. We present evidence that feeding a lard-based high-fat (HF) diet can protect mice from developing DSS-induced acute and chronic colitis and colitis-associated cancer (CAC) by significantly reducing tumour burden/incidence, immune cell infiltration, cytokine profile, and cell proliferation. We show that HF protection was associated with increased gut microbial diversity and a significant reduction in Proteobacteria and an increase in Firmicutes and Clostridium cluster XIVa abundance. Microbial functionality was modulated in terms of signalling fatty acids and bile acids (BA). Faecal secondary BAs were significantly induced to include moieties that can activate the vitamin D receptor (VDR), a nuclear receptor richly represented in the intestine and colon. Indeed, colonic VDR downstream target genes were upregulated in HF-fed mice and in combinatorial lipid-BAs-treated intestinal HT29 epithelial cells. Collectively, our data indicate that HF diet protects against colitis and CAC risk through gut microbiota and BA metabolites modulating vitamin D targeting pathways. Our data highlights the complex relationship between dietary fat-induced alterations of microbiota-host interactions in IBD/CAC pathophysiology.
The role of sentinel lymph node biopsy (SLNB) in ductal carcinoma in situ (DCIS) is controversial. This study evaluates the risk of clinically relevant SLN metastasis following a core needle biopsy (CNB) diagnosis of pure DCIS.Cases that underwent SLNB following a CNB diagnosis of pure DCIS at our institution over a 4.5 year period were evaluated. Parameters including the DCIS characteristics on CNB, the rate of upstaging to invasive carcinoma at excision and the SLNB result were recorded.Of 296 patients with a CNB diagnosis DCIS, 181 had SLNB (62%). The rate of invasion at excision in those undergoing SLNB was 30% (54/181). SLN metastasis was detected in 7/181 cases (4%), including 6 cases with isolated tumour cells only (3.5%) and only 1 case with a macro-metastatic deposit (0.5%).The risk of clinically significant SLN metastasis following a CNB diagnosis of DCIS is extremely low, despite a relatively high rate of upstaging to invasive carcinoma at excision. Our findings support the opinion that SLNB is not warranted following a CNB diagnosis of DCIS, particularly for those patients undergoing breast conservation surgery.
e14687 Background: Gastroesophageal cancer is a major cause of cancer-related mortality. HER2 is overexpressed in ~ 7-34% of gastroesophageal (GE) adenocarcinomas. The ToGA study, established the benefit of trastuzumab in combination with chemotherapy in HER2 positive metastatic GE tumours. In this study, 22% of patients were HER2 positive {immunohistochemistry (IHC)3+ or fluorescence insitu hybridization (FISH)(+)}. Potential heterogeneity of HER2 amplification, overexpression, and incomplete membrane staining of HER2 by IHC leaves some ambiguity in HER2 testing and definition of HER2 positive GE tumours. We report a multi-center Irish experience by examining HER2 status by IHC and FISH in GE tumours. Methods: HER2 testing was performed on adenocarcinoma biopsy or resection specimens of patients with early stage and metastatic GE tumors between 2008 - 2011. We defined HER2 positive as IHC3+ or FISH(+) {HER2:17ch ≥ 2}. In addition, age, gender, smoking history, histology, stage of disease, treatment, and survival data were recorded. Results: A total of136 Caucasian patients with early stage and metastatic GE cancers were identified. Median age was 69 yrs (ranging from 25 – 96). Data available for analysis was conducted from 111 patients with 10% FISH(+). There are 73 patients with early stage and 38 with metastatic disease. Five metastatic cases (13%) were FISH(+) (of whom 3 IHC3+, 1 IHC2+, 1 IHC1+), 33 cases were FISH(-). Sites of metastatic disease in the FISH(+) cohort were liver, peritoneal, and bone metastasis. In the FISH(-) group, sites of metastatic disease were predominantly liver. Interestingly CNS disease is seen exclusively in the FISH(-) cohort. Of the early stage patients, only 6 patients (8.2%) were FISH(+) (of whom 3 IHC3+, 2 IHC2+, 1 IHC1+). With respect to tumour heterogeneity of HER2 amplification, in IHC3+, 82% were FISH(+), IHC2+, 17% were FISH(+) and IHC1+, 6% were FISH(+). There was 100% concordance between IHC0 and FISH(-). Conclusions: HER2 positive GE adenocarcinomas in the analyzed cohort displays similar pattern of heterogeneity in IHC staining and FISH positivity but with lower incidence (10%) of HER2 amplification than was reported in the ToGA study. Further data on location, histological pattern and survival will be reported.
Aims Next-generation sequencing (NGS) is integral to the delivery of personalised medicine for targeted cancer therapy. Average turnaround times (TAT) from reference laboratories with advanced expertise in sequencing are typically 2–3 weeks. Prolonged TAT for biomarker analysis can adversely affect patient outcomes. The project aim was to establish an accredited NGS service integrated within a routine clinical diagnostic laboratory, in a designated tertiary cancer centre with no previous experience in NGS or bioinformatics. Methods Platform selected was the novel Ion Torrent Genexus Sequencer with automated onboard library preparation, templating, sequencing and data analysis, with subsequent reporting using Oncomine Reporter software. Entire workflow validation was performed with a targeted panel, the Oncomine Precision Assay, on formalin-fixed paraffin embedded clinical tumour samples. Oncomine Reporter software was used to report on variants including mutations, copy number variations and fusions across 50 key genes. Samples included surgical resections, biopsies, cytology and commercial reference material. Assessment of criteria included analytical sensitivity, specificity, limit of detection, accuracy, repeatability and reproducibility, with the establishment of performance metrics and quality parameters. Results High sensitivity, specificity and reproducibility were achieved. DNA/RNA input requirements optimised to >10 ng, and sequencing performance established with a limit of detection of 5% when depth of coverage of 2500X was reached. This NGS service attained ISO15189 accreditation with no non-conformances and >56% reduction in TAT. Conclusion Successful implementation, clinical validation and accreditation of a novel NGS technology was achieved in this institution, with a significantly improved TAT of results to oncologists