Assessment of Breast Cancer and Feasibility of Subtyping of Breast Cancer using Thoracoabdominal Staging Photon-counting Detector Computed Tomography

In this prospective study, we evaluated the performance of thoracoabdominal photon-counting detector computed tomography (PCD-CT) for breast cancer assessment with MRI as reference standard and iodine uptake as a potential marker for breast cancer subtyping.75 women (mean age: 55.8 years ± 13.9 [SD]) with 79 newly diagnosed breast cancers and indication for staging CT received a prone-positioned contrast-enhanced thoracoabdominal PCD-CT and a breast MRI. Cancer visibility and image quality (median 1/1, IQR 1/0) was rated excellent in PCD-CT on a 4-point Likert scale (1 = excellent, 4 = poor). Cancer size in PCD-CT correlated significantly with MRI ( p  < 0.001). Diagnostic accuracy was good for T-stage (accuracy 0.814), focality (0.810), axillary (0.842) and internal mammary lymph nodes (0.981), moderate for ductal carcinoma in situ (0.603). A significant lower maximum iodine uptake was revealed in cancer with ductal carcinoma in situ ( p  = 0.03), a significant lower mean iodine uptake in triple negative cancers ( p  = 0.003).Thoracoabdominal PCD-CT demonstrated excellent cancer visibility with convincing results for assessing cancer size, T-stage, and lymph node status. Iodine uptake shows promising associations with triple negative breast cancer.