Diagnostic Accuracy of Diffusion Weighted Magnetic Resonance Imaging (DW-MRI) for Skeletal Metastasis in Patients of Breast CA in Comparison with Bone Scan

Background: Breast carcinoma (CA) is one of the most prevalent cancers in women all across the globe. In current clinical practice, bone scan is main method for determining metastasis. However, use of various other imaging such as whole body magnetic resonance imaging (WB-MRI), enhanced with diffusion weighted protocol, can provide with a significant alternative method in early detection and assessment of various treatment options.Objective: To evaluate diagnostic accuracy of diffusion weighted MRI (DW-MRI) for skeletal metastasis in patients of breast CA taking bone scan as a gold standard.Methods: It was a cross sectional study, carried out at Department of Radiology, Mayo Hospital Lahore. 106 patients were enrolled and sent to the department of nuclear medicine for bone scan as part of their routine bone metastatic work-up. MRI including conventional sequences as well as DW sequence was then performed in all patients. Results: Mean age of patients was 51.2±11.7 years. On bones scan, metastasis were identified in 86 (81.1%) patients, while it was negative in 20 (18.2 %) patients. On DWI, metastatic disease was found in 73 (68.8%) patients, while it was absent in 33(31.1%) patients. Sensitivity, specificity, PPV and NPV of DWI-MRI were 80.1%, 80.0%, 94.5% and 48.4%, respectively.Conclusion: Sensitivity and specificity values of DWI are satisfactorily high in detecting metastatic disease in patients of breast CA. It can be a reliable and noninvasive alternate in detection of early disease.