膵臓がん検出のための意思決定支援ツール：オーストラリアのプライマリケアにおける外部検証

Background Pancreatic cancer is often diagnosed at an advanced stage with poor survival. Risk assessment tools have been developed to aid early diagnosis of pancreatic cancer in primary care settings (QCancer®, electronic Risk Assessment Tool (eRAT), and QPaC Tool) but have not been validated in the Australian setting. Aims To estimate and compare the performance of these tools for identifying patients with undiagnosed pancreatic cancer using Australian primary care data. Design and Setting A cohort study using linked primary care and cancer registry data from Victoria, Australia. Methods Patients presenting to primary care with signs/symptoms included in the tools (recorded in the primary care 'reason for encounter') were included. Diagnostic accuracy statistics for each tool (and their individual signs/symptoms) were compared. Results Pancreatic cancer patients were more likely (p<0.001) to present with new-onset diabetes, jaundice and unexpected weight loss pre-diagnosis than patients without pancreatic cancer. The most common pre-diagnostic presentations in pancreatic cancer patients were jaundice (29.0%), abdominal pain (25.6%), change in bowel habit (17.6%) and new-onset diabetes (14.8%). Jaundice, steatorrhoea and pancreatitis had the highest positive predictive values (PPV) for pancreatic cancer (1.96%, 1.77% and 0.89%, respectively). Among the tools, eRAT had the highest PPV of 1.37% (95% CI: 1.12, 1.66); the PPV for QPaC was 1.01% (95% CI: 0.82, 1.22) and QCancer® was 0.8% (95% CI: 0.54, 1.15). Conclusion When applied to Australian primary care data, none of the tools were strongly predictive of pancreatic cancer. New diagnostic models incorporating additional data could potentially improve their predictive performance.