Role of Whole-Body Magnetic Resonance Imaging in Detecting Metastasis in Patients With Known Cancer

Cancer continues to impose a significant global health burden, with metastatic disease being the leading cause of cancer-related mortality. Accurate detection and staging of metastases are essential for prognostication and treatment planning. Conventional imaging modalities, including contrast-enhanced computed tomography (CECT), have limitations in detecting early or subtle metastatic lesions. Whole-body magnetic resonance imaging (WB-MRI), particularly with diffusion-weighted imaging (DWI), has emerged as a radiation-free technique that enables comprehensive evaluation with high soft-tissue contrast. Therefore, this study aimed to evaluate the diagnostic performance of WB-MRI, including DWI, in detecting nodal, skeletal, and visceral metastases in patients with known malignancies and to compare its performance with CECT on a patient-based analysis.

This analytical cross-sectional study was conducted in the Department of Radiodiagnosis at Aarupadai Veedu Medical College and Hospital, Puducherry, over a period of six months. Eighty patients aged 18-60 years with histopathologically confirmed malignancy were included. All participants underwent CECT of the neck, thorax, and abdomen, followed by WB-MRI using a 1.5-T system with diffusion-weighted sequences. Imaging findings were documented and, wherever feasible, correlated with histopathology or cytology. Data were analyzed using descriptive statistics and the chi-square test in Statistical Package for the Social Sciences, version 26.0 (IBM Corp., Armonk, NY; 2019). A p value of <0.05 was considered statistically significant.

The mean age of the participants was 53.39 ± 8.16 years, with a slight female predominance. Carcinoma of the cervix and breast carcinoma were the most common primary malignancies. WB-MRI demonstrated significantly higher sensitivity and specificity than CT in detecting nodal, skeletal, and visceral metastases. It showed excellent performance in detecting skeletal metastases and superior accuracy in identifying nodal and visceral involvement, with statistically significant differences compared to CT.

WB-MRI outperforms CT in the comprehensive detection of metastatic disease across multiple organ systems. Its high diagnostic accuracy, absence of ionizing radiation, and ability to detect early metastatic changes support its role as a reliable imaging modality for staging and follow-up in oncology.