Diffusion kurtosis imaging in predicting the chemotherapeutic response of colorectal liver metastases: The result of the FDZL-MRinCLM study.

Abstract

e16034 Background: Colorectal liver metastatic (CLM) patients are a special population who have potential of cure with effective conversion treatment. The conventional radiological imaging commonly evaluates the response 6-8 weeks after the medication. A response marker for earlier prediction could avoid further use of ineffective drugs and guide the medical change for optimal regimen. This study is to evaluate the feasibility of early parameter change assessed by functional MR in predicting clinical response to chemotherapy and investigate its prognostic value in CLM patients. Methods: From August 2016, CLM patients were consecutively enrolled and examined by functional MRI with diffusion kurtosis imaging (DKI) sequence of liver at baseline and one cycle after the initiation of chemotherapy. The whole-lesion histogram and texture analyses of DKI was analyzed and features were extracted from the inline-generated parametric maps included K and D. The primary endpoint of the study was the DKI-predicted ORR of liver metastases, and the secondary endpoint were the DKI-predicted PFS and OS. The efficacy response was assessed by the RECIST Version 1.1 every two cycles of treatment. The association between the baseline DKI parameters, value change ratio (delta-DKI parameters = (Valuebaseline-Valuecycle1)/ Valuebaseline) and ORR and survival were examined. Results: Up to Dec 2019, one-hundred consecutively enrolled patients (65 Male, 35 Female, Age from 30-75 years old) received the treatment (FOLFOX 13, XELOX 53, FOLFIRI 34) and complete the liver functional MRI scanning. A total of 42 responding (CR+PR) and 58 nonresponding (SD+PD) patients were evaluated. Lower baseline D values (D-mean, D-std and D-median, P < 0.005), higher baseline K values (K-mean, K-median, P < 0.005), lower delta-D values (delta-D-DiffEntropy, P = 0.000) and higher delta-K value (delta-K-median, P = 0.022) were significantly associated with a higher ORR, and the combination of all the significant parameters yielded an AUC of 0.834 (sensitivity 76.19%, specificity 77.59%) in predicting the early efficacy of CLMs. Patients with higher delta-D-diffEntropy value showed a longer PFS (9.0 vs 5 mons, P = 0.002) and OS (30.5 vs 14.8 mons, P = 0.032). Conclusions: The baseline value and early parameter change in DKI might be a good predictive marker for the chemotherapeutic response of CLMs, and the early increase of D value in liver metastases could be a promising factor for survival of patients undergoing standard chemotherapy. Clinical trial information: NCT03088163 .