Quantifying downstream impact of inappropriate staging imaging in a cohort of veterans with low- and intermediate-risk incident prostate cancer

Abstract

IntroductionAccording to current National Comprehensive Cancer Network guidelines, routine imagining for staging low-risk prostate cancer is not recommended. However, extensive overuse of guideline-discordant imaging continues to persist. Incidental findings are common on imaging and little is known about the optimal management. Rates of incidental findings vs. false positive diagnosis from inappropriate imaging are poorly understood and have yet to be quantified for low- and intermediate-risk prostate cancer patients. ObjectiveTo determine the frequency of positive radiologic findings in patients with low- and intermediate-risk prostate cancer during initial staging at VA New York Harbor Healthcare System. MethodsWe retrospectively reviewed all low- and intermediate-risk prostate cancer patients’ medical records from the VA New York Harbor Healthcare System for diagnosis from 2005 to 2015. We reviewed each individual's prebiopsy prostate specific antigen (PSA), Gleason score, and clinical stage. We also determined if imaging obtained yielded a false positive, incidental finding, or if metastatic disease occurred within the 6 months following initial diagnosis. ResultsThere were 414 men, who were classified as low- to intermediate-risk prostate cancer and underwent inappropriate staging imaging of 4,306 men diagnosed with prostate cancer. Of these 414 men, 178 (43%) had additional follow-up imaging for positive findings. We calculated an incidental finding rate of 10% and a false positive rate of 38% for patients. Five (1%) patients had metastatic disease. ConclusionDespite guideline recommendations, imaging overuse remains an issue for low-intermediate-risk prostate cancer patients. The false positive rate found in this analysis is alarmingly high at 38%. This use of scans is burdensome to the healthcare system and patient. This study highlights the frequency of inappropriate imaging and its negative consequences.