Purpose: This study aims to investigate the clinical utility of multiparametric MRI features in distinguishing between germinal center B-cell-like (GCB) and non-germinal center B-cell-like (non-GCB) subtypes of primary central nervous system (CNS) diffuse large B-cell lymphoma (DLBCL), with the objective of establishing a non-invasive diagnostic protocol that could potentially reduce dependence on invasive histopathological confirmation.
Methods: This study retrospectively included 160 patients with primary CNS DLBCL (53 GCB subtype and 107 non-GCB subtype) confirmed by pathology at Huashan Hospital, Fudan University, from March 2013 to December 2024. All patients underwent multiparametric MRI scans, including T1WI, T2-FLAIR, DWI, and T1-CE. Three senior radiologists collected and assessed the clinical and imaging features of the patients, including: gender, age, number of lesions, location, ADC ratio, maximum diameter, minimum diameter, presence of cystic or necrotic changes, regularity of margins, “fist sign”, “horn sign”, “umbilication sign”, “butterfly sign”, meningeal involvement, ependymal involvement, degree of peritumoral edema, and mass effect. Statistical analyses were performed with SPSS 29.0. Continuous variables were compared using t-tests, and categorical/ordinal variables with χ² or Mann–Whitney U tests (significance set at P < 0.05). Area-under-the-curve (AUC) values were derived from non-parametric ROC analysis using the DeLong method.
Results: Significant differences were observed in multiple MRI features between the GCB and non-GCB types of DLBCL. The non-GCB type was more likely to present as a solitary lesion (P = 0.006), had a higher incidence of cystic or necrotic changes (P = 0.013), irregular margins (P = 0.016), ependymal involvement (P = 0.046), and exhibited the “fist sign” (P = 0.034) and more severe peritumoral edema (P = 0.047).
Conclusions: Significant differences in MRI features exist between the GCB and non-GCB types of primary CNS DLBCL, providing a new approach for non-invasive subtyping of DLBCL in clinical practice.
Keywords: Diffuse large B-cell lymphoma; Germinal center B-cell-like; Multiparametric MRI; Non-invasive diagnosis.