Radiological factors associated with misstaging of pancreatic ductal adenocarcinoma

Abstract

Background: A multidisciplinary approach to patients with pancreatic ductal adenocarcinoma (PDAC) is the standard of care and accurately staging is vital to developing a treatment plan. Unfortunately, >20% of patients evaluated at high volume centers are determined to have different stage of disease than initially believed. Factors contributing to the misstaging are poorly understood. Methods: Patients presenting with PDAC to the Johns Hopkins Hospital (JHH) pancreatic multidisciplinary clinic (PMDC) from 2006 to 2014 who had scans performed at both an outside hospital (OH) and JHH within 30 days of each other were included. Two radiologists, blinded to reports of these scans, reviewed the OH and JHH scans. Factors contributing to PDAC patients' misstaging were identified. Results: Of patients who presented at PMDC during the study period, 100 were included in the study. When OH scans were read by JHH radiologists, 36% had change in stage. New pancreas- protocol CT scans performed at JHH resulted in change in stage of 25% patients. For patients with a change in stage at JHH, a majority (80%) had more advanced disease than initially believed i.e. change from resectable, borderline or locally-advanced to metastatic disease. Only two (8.0%) patients had less disease than initially anticipated i.e. resectable disease at JHH after OSH evaluation showing more advanced disease. Blinded radiologist review revealed the causes of misstaging were: poor contrast timing (N = 11, 44.0%), low contrast enhancement (N = 8, 32.0%), lack of MPR/3D sections (N = 2, 8.0%), slice thickness (N = 2, 8.0%), image noise (N = 4, 16.0%), disease progression (N = 2, 8.0%) and presumed radiologist experience (N = 6, 24.0%). Conclusion: Approximately a quarter of PDAC patients in the study were misstaged on imaging due to multiple radiological factors. Attention to these factors can significantly reduce misstaging.