Influence of Initial Imaging Modality on Peri-Diagnostic Outcomes Among Pancreatic, Liver, Ovarian, and Bladder...

The diagnostic evaluation for abdominal and pelvic cancers without routine screening programs, such as pancreatic, liver, ovarian, and bladder cancers, can vary significantly in pathway and timing. Efficient and timely diagnosis is desirable in patients with a suspicion of cancer. We characterized real-world diagnostic pathways and examined the association of first imaging modality with measures of diagnostic efficiency in these cancers.

We conducted a retrospective cohort study using Surveillance, Epidemiology and End Results cancer registry data linked with Medicare claims from 2010 to 2019. Patients aged ≥65 years diagnosed with incident pancreatic, liver, ovarian, or bladder cancer were included. We estimated unadjusted timing, cost, and healthcare resource utilization from first imaging to diagnosis, and from diagnosis to treatment initiation by cancer type. Using negative binomial count models, we evaluated the association between computed tomography (CT) scan as the first imaging procedure and both time to diagnosis and number of imaging procedures used in the diagnostic pathway.

Among 169 781 patients (48 751 pancreatic; 24 493 liver; 16 537 ovarian; and 80 000 bladder), CT scan was the most common initial imaging test (51%-65%). Patients who received a CT scan first experienced significantly shorter time to diagnosis (29-42 days faster) and required fewer imaging procedures (0.25-0.70 fewer) compared with other imaging modalities (P < .001). Higher comorbidity scores were associated with longer, more complex diagnostic pathways.

CT scans as the first imaging test were associated with greater diagnostic efficiency in abdominal and pelvic cancers. These findings provide a benchmark for evaluating emerging diagnostic technologies and optimizing cancer diagnostic pathways.