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Background: Aboriginal and Torres Strait Islander (Indigenous) Australians have an increased prevalence of coronary artery disease and present at a younger age for coronary artery bypass graft surgery (CABG) when compared to non‐Indigenous Australians. Studies have reported postoperative outcomes in Indigenous people to be less favourable. Therefore, the aim of this study is to evaluate long term mortality between Indigenous and non‐Indigenous people post‐CABG. Methods: We analysed data on all patients who underwent isolated CABG, with and without cardiopulmonary bypass, at our institution between January 1998 to September 2008. There were 33 395 person‐years of survival for analysis with a median follow‐up of 13 years (Interquartile range (IQR): 8–16 years). We analysed all‐cause mortality with the Kaplan–Meier graph and log‐rank test. Univariate and multivariate analysis was performed using a Cox proportional hazards model. Results: The mean age at presentation for Indigenous people was 52 years compared to 65 yr for non‐indigenous people. There were 1431 (52.1%) deaths by the study census date, with the overall mortality for Indigenous patients at 49.8% (n = 147) and 52.4% for non‐Aboriginal patients (n = 1284). The age and comorbidities adjusted hazard ratio (HR) for all‐cause late mortality (median years) was HR = 1.712 (95% CI: 1.288–2.277, p < 0.001). Conclusion: Indigenous patients present for CABG at a younger age and have a higher prevalence of comorbidities. Our study demonstrates they have a higher risk of propensity adjusted all‐cause long term mortality. Primary and secondary prevention strategies, tailored to Indigenous people, may improve health outcomes in the long‐term post‐CABG. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) is one of the most common cancers in the world. A newly proposed integrated pathway comprising traditional, alternate, and serrated pathways by genetic and epigenetic factors was defined recently and hypothesized to play a role in the pathogenesis of CRC; however, to the authors' knowledge, there is a paucity of information regarding these proposed molecular pathways in different ethnic groups.Methods: Molecular characterization of 770 CRC specimens was performed for microsatellite instability, BRAF, and KRAS by polymerase chain reaction and 500 cases for CpG island methylator phenotype (CIMP) high phenotype by MethyLight technology. Tumors were assigned to different molecular pathways and examined for clinicopathological correlation and survival analysis.Results: The traditional pathway constituted 33.4% of CRC cases, the alternate pathway comprised 11.6%, and the serrated molecular pathway accounted for only 0.8% of Middle Eastern CRC cases. Approximately 54.2% of CRC cases did not qualify to fit into any pathway and thus were designated as an unassigned group. Molecular pathways were found to be significantly associated with tumor site and grade. A subset of cases with an uncategorized pathway demonstrated a significant survival difference (P = .0079).Conclusions: The serrated pathway was found to account for a very low percentage of the CRC patient cohort in the current study. The unassigned group accounted for the majority of Middle Eastern CRC cases, and therefore methods of CRC pathway analysis might not be applicable to this ethnic group. The current study demonstrates the need to unravel the molecular genetic basis of this disease to further subcategorize these CRC cases. It also identifies a need for further studies on different populations for a better understanding of their exact role and incidence. [ABSTRACT FROM AUTHOR]

BACKGROUND Lynch syndrome (LS; hereditary nonpolyposis colorectal cancer) is a common cause of hereditary colorectal cancer (CRC). CRC is the most common cancer diagnosed among males in Saudi Arabia but to the authors' knowledge there is a lack of data regarding the prevalence of LS in patients with CRC. There currently are no clear guidelines for the selection criteria for these patients to screen for LS. METHODS A comprehensive molecular characterization was performed in a cohort of 807 CRC cases by immunohistochemical and microsatellite analysis using polymerase chain reaction. BRAF mutation screening, high CpG island methylator phenotype, and analysis for germline mutations were performed in 425 CRC samples. These were all high microsatellite instability (MSI-H) samples (91 cases), all low MSI samples (143 cases), and selected cases from the microsatellite stable group (191 cases) that met revised Bethesda guidelines. RESULTS Polymerase chain reaction identified 91 MSI-H cases (11.3%) and sequencing revealed mismatch repair germline mutations in 8 CRC cases only. Of the total of 807 CRC cases, these 8 cases (0.99%) were MSI-H, met the revised Bethesda guidelines, and did not harbor BRAF mutations. CONCLUSIONS The results of the current study confirmed cases of LS in approximately 1.0% of CRC samples and reflects the efficacy of screening among MSI-H cases that lack BRAF mutations. This comprehensive study from Saudi Arabia will help in implementing a universal screening/reflex testing strategy in a clinical setting in Saudi Arabia and in conducting a national screening program that benefits both patients and their relatives. Cancer 2015;121:1762-1771. © 2015 American Cancer Society. [ABSTRACT FROM AUTHOR]