Cost-Effectiveness of Integrated Fluorodeoxyglucose PET/MR With Low-Dose Chest CT for Initial Staging of Locally Advanced Breast Cancer.

OBJECTIVE: To evaluate the cost-effectiveness of an integrated fluorodeoxyglucose (FDG) PET/MR-based staging strategy supplemented with low-dose chest CT compared with guideline-based conventional imaging in patients with newly diagnosed invasive ductal breast cancer.

METHODS: A decision-analytic model was developed to compare conventional multimodality staging (contrast-enhanced CT, bone scintigraphy, and breast MR) with an integrated FDG PET/MR-based staging strategy supplemented with low-dose chest CT. The primary analysis focused on patients with presumed clinical stage III disease; a secondary analysis examined high-risk stage IIB patients. Model inputs included published diagnostic performance data and standardized reimbursement proxies. Outcomes included cost per patient correctly staged for distant metastases, incremental cost-effectiveness ratios, and a supplementary short-term quality-adjusted life-year analysis. Deterministic and probabilistic sensitivity analyses were performed.

RESULTS: In presumed stage III disease, the PET/MR-based strategy improved model-derived staging accuracy compared with conventional imaging (97% [95% uncertainty interval {UI}: 94%-99%] versus 70% [95% UI: 64%-76%]) and reduced false-positive findings. Although associated with higher upfront imaging costs, the incremental cost-effectiveness ratio was approximately $3,000 per additional patient correctly staged (95% UI: $1,500-$6,500). Results remained robust across wide pricing assumptions. In high-risk stage IIB patients, cost-effectiveness was more sensitive to metastatic prevalence. The short-term quality-adjusted life-year analysis demonstrated modest short-term utility gains favoring PET/MR.

DISCUSSION: Integrated FDG PET/MR with adjunct low-dose chest CT is economically attractive in patients with presumed locally advanced breast cancer. Selective implementation in high-risk populations may improve diagnostic efficiency while mitigating downstream costs associated with fragmented imaging pathways.