Evaluation of liver metastasis in patients with breast cancer: Comparison of single-phase abdominopelvic CT and multi-phase liver CT.

Abstract

To compare the usefulness of multi-phase liver CT and single-phase abdominopelvic CT (APCT) in evaluating liver metastasis in newly diagnosed breast cancer patients. In this retrospective study, a total of 7621 newly diagnosed breast cancer patients (mean age, 49.7years ± 10.1; 7598 women) who underwent single-phase APCT (n = 5536) or multi-phase liver CT (n = 2085) for staging workup between January 2016 and June 2019 were included. The staging CTs were categorized as having no metastasis, probable metastasis, or indeterminate lesions. MRI referral rate (proportion of patients underwent additional liver MRI), negative MRI rate (patients without true hepatic metastasis / patients underwent liver MRI), true positive CT rate (patients with true metastasis / patients categorized as probable metastasis), true metastasis rate among CT indeterminate (patients with true metastasis / patients categorized as indeterminate lesions), and overall liver metastasis rate were compared between the two groups. Further, the radiation dose was recorded for every patient. The proportions of having no metastasis and indeterminate lesions on the results of CT interpretation were significantly different between the two groups (P = 0.006). However, the MRI referral rate, negative MR rate, true positive CT rate, true metastasis rate among CT indeterminate, and overall liver metastasis rate were not significantly different between the two groups. Radiation dose of multi-phase CT was three times higher than that of single-phase CT. Multi-phase liver CT has little benefit over single-phase APCT in assessing liver metastasis in patients with breast cancer.