Dr Peter Pockney

© 2018 Elsevier Inc. Background: Circulating tumour DNA (ctDNA) has emerged as an excellent candidate for the future of liquid biopsies for many cancers. There has been growing interest in blood-based liquid biopsy because of the potential of ctDNA to produce a noninvasive test that can be used for: the diagnosis of colorectal cancer, monitoring therapy response, and providing information on overall prognosis. The aim of this review was to collate and explore the current evidence regarding ctDNA as a screening tool for colorectal cancer (CRC). Methods: A systematic review of published articles in English over the past 20 y was performed using Medline, Embase, and Cochrane databases on May 23, 2017. After a full-text review, a total of 69 studies were included. Two assessment tools were used to review and compare the methodological quality of these studies. Results: Among the 69 studies included, 17 studies reviewed total cfDNA, whereas six studies looked at the DNA integrity index and 15 focused on ctDNA. There were a total of 40 studies that reviewed methylated cfDNA with 19 of these focussing specifically on SEPT9. Conclusions: The results of this review indicate that methylated epigenetic ctDNA markers are perhaps the most promising candidates for a blood-based CRC-screening modality using cell-free (cf) DNA. Methylated cfDNA appears to be less specific for CRC compared to ctDNA; however, they have demonstrated good sensitivity for early-stage CRC. Further research is required to determine which methylated cfDNA markers are the most accurate when applied to large cohorts of patients. In addition, reliable comparison of results across multiple studies would benefit from standardization of methodology for DNA extraction and PCR techniques in the future.

© 2017 The American Society of Colon and Rectal Surgeons, Inc. BACKGROUND: Lower GI hemorrhage is a common source of morbidity and mortality. Tranexamic acid is an antifibrinolytic that has been shown to reduce blood loss in a variety of clinical conditions. Information regarding the use of tranexamic acid in treating lower GI hemorrhage is lacking. OBJECTIVE: The aim of this trial was to determine the clinical efficacy of tranexamic acid when used for lower GI hemorrhage. DESIGN: This was a prospective, double-blind, placebo-controlled, randomized clinical trial. SETTINGS: The study was conducted at a tertiary referral university hospital in Australia. PATIENTS: Consecutive patients aged >18 years with lower GI hemorrhage requiring hospital admission from November 2011 to January 2014 were screened for trial eligibility (N = 265). INTERVENTIONS: A total of 100 patients were recruited after exclusions and were randomly assigned 1:1 to either tranexamic acid or placebo. MAIN OUTCOME MEASURES: The primary outcome was blood loss as determined by reduction in hemoglobin levels. The secondary outcomes were transfusion rates, transfusion volume, intervention rates for bleeding, length of hospital stay, readmission, and complication rates. RESULTS: There was no difference between groups with respect to hemoglobin drop (11 g/L of tranexamic acid vs 13 g/L of placebo; p = 0.9445). There was no difference with respect to transfusion rates (14/49 tranexamic acid vs 16/47 placebo; p = 0.661), mean transfusion volume (1.27 vs 1.93 units; p = 0.355), intervention rates (7/49 vs 13/47; p = 0.134), length of hospital stay (4.67 vs 4.74 d; p = 0.934), readmission, or complication rates. No complications occurred as a direct result of tranexamic acid use. LIMITATIONS: A larger multicenter trial may be required to determine whether there are more subtle advantages with tranexamic acid use in some of the secondary outcomes. CONCLUSIONS: Tranexamic acid does not appear to decrease blood loss or improve clinical outcomes in patients presenting with lower GI hemorrhage in the context of this trial. see Video Abstract at http://links.lww.com/DCR/A453.