Breast Density and Risk of Interval Cancers: The Effect of Annual Versus Biennial Screening Mammography Policies in Canada.

Regular screening mammography reduces breast cancer mortality. However, in women with dense breasts, the performance of screening mammography is reduced, which is reflected in higher interval cancer rates (ICR). In Canada, population-based screening mammography programs generally screen women biennially; however, some provinces and territories offer annual mammography for women with dense breast tissue routinely and/or on recommendation of the radiologist. This study compared the ICRs in those breast screening programs with a policy of annual vs. those with biennial screening for women with dense breasts. Among 148,575 women with dense breasts screened between 2008 to 2010, there were 288 invasive interval breast cancers; screening programs with policies offering annual screening for women with dense breasts had fewer interval cancers 63/70,814 (ICR 0.89/1000, 95% CI: 0.67-1.11) compared with those with policies of usual biennial screening 225/77,761 (ICR 1.45 /1000 (annualized), 95% CI: 1.19-1.72) i.e. 63% higher (p = 0.0016). In screening programs where radiologists' screening recommendations were able to be analyzed, a total of 76,103 women were screened, with 87 interval cancers; the ICR was lower for recommended annual (65/69,650, ICR 0.93/1000, 95% CI: 0.71, 1.16) versus recommended biennial screening (22/6,453, ICR 1.70/1000 (annualized), 95%CI: 0.70, 2.71)(p = 0.0605). Screening program policies of annual as compared with biennial screening in women with dense breasts had the greatest impact on reducing interval cancer rates. We review our results in the context of current dense breast notification in Canada.

Second-line Chemotherapy Prolongs Survival in Real World Patients With Advanced Biliary Tract and Gallbladder Cancers: A Multicenter Retrospective Population-based Cohort Study.

BACKGROUND: Limited evidence is available regarding the survival benefit of second-line therapy in real world patients with advanced biliary tract and gallbladder cancer. Until very recently, there was a lack of randomized clinical trials to address this important question. In this multicenter population-based cohort study, the authors evaluated whether second-line therapy improves the survival of real world patients with advanced biliary tract and gallbladder cancer. METHODS: Patients with biopsy-proven advanced biliary tract and gallbladder cancer who were diagnosed during the period of 2006 to 2015 and had received first-line chemotherapy were assessed. Cox proportional multivariate analysis was performed to determine the survival benefit of second-line therapy. RESULTS: One hundred thirty-six eligible patients with a median age of 66 years and male:female ratio of 1:1.34 were identified. Sixty-eight percent of patients had metastatic disease. Primary tumor sites were as follows: gallbladder 31%, intrahepatic cholangiocarcinoma 36%, extrahepatic bile duct 23%, and ampullary cancer 10%. Overall, 37% of patients received second-line therapy. The median overall survival of the treatment group was 17 months (95% confidence interval [CI]: 12.5-21.5) compared with 7 months (95% CI: 5.3-8.7) in the control (P<0.0001). Patients who received combination chemotherapy had a median overall survival of 20 months (14.0-26.1) compared with 17 months (13.5-20.5) if they received single-agent second-line therapy (P=0.73). Multivariate analysis of second-line therapy, hazard ratio: 0.55 (95% CI: 0.36-0.83) and neutrophil to lymphocyte ratio >2, HR: 1.10 (1.05-1.15) showed a significant correlation with survival. CONCLUSIONS: This well-designed population-based retrospective cohort study suggests that second-line chemotherapy improves survival of real world patients with advanced biliary tract and gallbladder cancers and should be offered to the patients who are potential candidates for chemotherapy.

A task-based analysis of machinery entanglement injuries among Western Canadian farmers.

Machinery entanglements are a leading cause of hospitalized injury on Canadian farms. This study evaluates the role farm tasks play in the occurrence of machinery entanglement events. A retrospective case series of 41 entanglement injuries involving 35 farm-machinery types was assembled. Only a few limited tasks were implicated in the majority of entanglements. These tasks were as follows: (1) field adjustments of machinery; (2) product handling and conveyance; and (3) driveline attachments and servicing. Hazards inherent and common to these tasks affected the behavior of farmers, leading to entanglements. This study establishes a need to identify hazards and assess risks associated with different tasks involving the use of farm machinery under actual field situations. Systemic changes are required to improve existing machinery safety practices through engineering, work methods, and work practice modifications. In addition to design solutions, occupational health and safety strategies should consider activities associated with hazardous situations to inform the content of injury prevention efforts.

Operational safety practices as determinants of machinery-related injury on Saskatchewan farms.

Agricultural machinery is a major source of injury on farms. The importance of machinery safety practices as potential determinants of injury remains incompletely understood. We examined two such safety practices as risk factors for injury: (1) the presence of safety devices on machinery and (2) low levels of routine machinery maintenance. Our data source was the Saskatchewan Farm Injury Cohort baseline survey (n=2390 farms). Factor analysis was used to create measures of the two operational safety practices. The farm was the unit for all analyses and associations were evaluated using multiple Poisson regression models. Limited presence of safety devices on machinery during farm operations was associated with higher risks for injury (RR 1.94; 95% CI 1.13-3.33; p(trend)=0.02). Lower routine maintenance scores were associated with significantly reduced risks for injury (RR 0.54; 95% CI 0.29-0.98; p(trend)=0.05). The first finding implies that injury prevention programs require continued focus on the use of safety devices on machinery. The second finding could indicate that maintenance itself is a risk factor or that more modern equipment that requires less maintenance places the operator at lower risk. These findings provide etiological data that confirms the practical importance of operational safety practices as components of injury control strategies on farms.