Diffusion-weighted imaging (DWI) in diagnosis, staging, and treatment response assessment of multiple myeloma: a systematic review and meta-analysis

Objective To evaluate the role of diffusion-weighted imaging (DWI) in the initial diagnosis, staging, and assessment of treatment response in patients with multiple myeloma (MM). Materials and methods A systematic literature review was conducted in PubMed, the Cochrane Library, EMBASE, Scopus, and Web of Science databases. The primary endpoints were defined as the diagnostic performance of DWI for disease detection, staging of MM, and assessing response to treatment in these patients. Results Of 5881 initially reviewed publications, 33 were included in the final qualitative and quantitative meta-analysis. The diagnostic performance of DWI in the detection of patients with MM revealed pooled sensitivity and specificity of 86% (95% CI: 84–89) and 63% (95% CI: 56–70), respectively, with a diagnostic odds ratio (OR) of 14.98 (95% CI: 4.24–52.91). The pooled risk difference of 0.19 (95% CI: − 0.04–0.42) was reported in favor of upstaging with DWI compared to conventional MRI ( P value = 0.1). Treatment response evaluation and ADC mean value changes across different studies showed sensitivity and specificity of approximately 78% (95% CI: 72–83) and 73% (95% CI: 61–83), respectively, with a diagnostic OR of 7.21 in distinguishing responders from non-responders. Conclusions DWI is not only a promising tool for the diagnosis of MM, but it is also useful in the initial staging and re-staging of the disease and treatment response assessment. This can aid clinicians with earlier initiation or change in treatment strategy, which could have prognostic significance for patients.