Prediction of the response of ocular adnexal lymphoma to chemotherapy using combined pretreatment dynamic contrast-enhanced and diffusion-weighted MRI

Background There are no established biomarkers predictive of the efficacy of treatment for ocular adnexal lymphoma (OAL). Purpose To evaluate the effectiveness of pretreatment dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging (DWI) in predicting the response of OAL to chemotherapy. Material and Methods Twenty-one patients, who were pathologically diagnosed with OAL, were retrospectively analyzed. According to the National Comprehensive Cancer Network (NCCN) response evaluation criteria for non-Hodgkin's lymphoma, patients were divided into responders (n = 14) and non-responders (n = 7). The volume transfer constant (K^trans), rate constant (K_ep), extracellular extravascular volume fraction (Ve), and apparent diffusion coefficient (ADC) were computed. Two independent-sample tests were applied for statistical analysis. For significantly different parameters, receiver-operator characteristics curve analysis was performed. Results The K^trans value (min^-1), K_ep value (min^-1), and ADC value (10^-3mm²/s) were 0.76 ± 0.36 vs. 0.47 ± 0.18 (mean ± SD), 4.43 ± 1.29 vs. 3.14 ± 1.37, and 0.51 ± 0.12 vs. 0.66 ± 0.15, respectively, in the responders and non-responders groups. Significant differences were found between the two groups regarding these parameters ( P < 0.05). However, no significant difference was observed in Ve (min^-1) between the groups ( P > 0.05). K^trans, K_ep, and ADC had a moderately predictive sensitivity or specificity. When K^trans and ADC or the three parameters were combined, a considerably higher sensitivity (85.7%) and specificity (85.7%) with a significant discriminative accuracy (area under the curve = 0.929; P = 0.002) was found. Conclusion K^trans, K_ep, and ADC could potentially predict OAL response to chemotherapy. A combination of these DWI and DCE-MRI quantitative parameters might increase sensitivity and specificity.