Brain CT for Diagnosis of Intracranial Disease in Ambulatory Patients with Cancer: Assessment of the Diagnostic Value of Scanning without Contrast prior to with Contrast
Year: 2025
Type: article
Study design: Observational Study
Abstract: BACKGROUND AND PURPOSE: Brain imaging with MRI or CT is standard in screening for intracranial disease among ambulatory patients with cancer. Though MRI offers greater sensitivity, CT is frequently employed because of its accessibility, affordability, and faster acquisition time. However, the necessity of routinely performing a noncontrast CT with the contrast-enhanced study is unknown. This study evaluates the clinical and economic utility of the noncontrast portion of the brain CT examination. MATERIALS AND METHODS: A board-certified neuroradiologist reviewed 737 brain CT reports from outpatients at The University of Texas MD Anderson Cancer Center who underwent contrast and noncontrast CT for cancer staging (October 2014 to March 2016) to assess if clinically meaningful findings were identified only on noncontrast CT. A Generative Pretrained Transformers-3 (GPT-3) model was then fine-tuned to extract reports with a high likelihood of unique and meaningful noncontrast findings from 1980 additional brain CT reports (January 2017 to April 2022). These reports were manually reviewed by 2 neuroradiologists, with adjudication by a third reviewer if needed. The incremental cost-effectiveness ratio of noncontrast CT inclusion was then calculated based on Medicare reimbursement and the 95% CI of the proportion of all reports in which noncontrast CT was necessary for identifying meaningful findings. RESULTS: Seven of 737 reports in the initial data set revealed meaningful findings unique to the noncontrast CT, all of which were hemorrhage. The GPT-3 model identified 145 additional reports with a high unique noncontrast CT finding likelihood for manual review from the second data set of 1980 reports. Nineteen of these reports were found to have unique and meaningful noncontrast CT findings. In total, 0.96% (95% CI: 0.63-1.40) of reports had meaningful findings identified only on noncontrast CT. The incremental cost-effectiveness ratio for the identification of a single meaningful finding on noncontrast CT missed on the contrast-enhanced study was $1855 to $4122. CONCLUSIONS: In brain CT for ambulatory screening for intracranial disease in patients with cancer, noncontrast CT offers limited additional diagnostic value compared with contrast-enhanced CT alone. Considering the associated financial cost, workload, and patient radiation exposure associated with performing a noncontrast CT, contrast-enhanced brain CT alone is sufficient for cancer staging in patients with asymptomatic cancer.
DOI: 10.3174/ajnr.a8995
Authors: Ethan Wang, Azad Darbandi, Long Tu, Leomar Y. Ballester, Charles de Jesus Morales, Melissa Chen, Maria K. Gule-Monroe, Jason M. Johnson
Language: English
Subfield: Pulmonary and Respiratory Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
OpenAlex ID: W4414084271