The Role of Pretherapeutic Diffusion-Weighted MR Imaging Derived Apparent Diffusion Coefficient in Predicting Clinical Outcomes in Immunocompetent Patients with Primary CNS Lymphoma: A Systematic Review and Meta-Analysis

Objective: This systematic review and meta-analysis aimed to confirm the role of Apparent Diffusion Coefficient (ADC) values in predicting the prognosis of PCNSL patients based on previous studies. Methods: A systematic review with meta-analysis was conducted on related articles PubMed, Scopus, Sciencedirect, Cochrane, DOAJ, and Embase databases with last updated search on November 30, 2021. This systematic review and meta-analysis included a total of four studies. Result: All studies that examined the association between pretherapeutic ADC values and OS and PFS discovered that lower ADC values were associated with significantly shorter OS and PFS. The analysis revealed that patients with low ADC values had a higher risk of death than those with high ADC values, with a pooled HR of 0.24 (95% CI: 0.10–0.56; Z = 3.26; p = 0.001). A meta-analysis of five data from three studies examining the association between ADC values and PFS was also conducted using a fixed-effects model due to the low heterogeneity values (I2 = 4%; p = 0.38). The data analysis revealed that the pooled HR was 0.25 (95% confidence interval [CI]: 0.14–0.44, Z = 4.18; p 0.00001). Conclusion: Patients with low ADC values had significantly shorter overall survival and progression-free survival than those with high ADC values, so ADC values assessment prior to initial therapy administration can provide clinicians with valuable information about the prognosis of PCNSL.