Quantitative Pretreatment CT Parameters as Predictors of Tumor Response of NET Liver Metastasis to TAE

PURPOSE: To assess whether parameters on preprocedural CT can be utilized to predict the response of NETLM to TAE. METHODS: We retrospectively reviewed 135 target lesions from 48 NETLM patients who underwent TAE and with complete preprocedural multiphasic CT. Parameters on preprocedural CT including longest diameter, mean attenuation value in non-enhanced, arterial and portal-venous phases were collected from each target lesion. Radiological responses were assessed according to RECIST 1.1. The parameters of responder lesions and non-responder lesions were compared. Arterial enhancement index (AEI) and portal-venous enhancement index (PEI) were calculated. The predictive function of AEI and PEI on tumor response were analyzed by ROC curve. RESULTS: A total of 72.6% target lesions had a partial response (PR). For patients, the objective response rate (ORR) was 72.9%. Mean attenuation values of responder lesions were significantly higher than non-responder lesions in both arterial and portal-venous phases (105.36 ± 37.24 vs. 76.01 ± 19.19, p < 0.001; 96.6 ± 24.0 vs. 82.1 ± 21.3, p = 0.002). ROC curve showed that both AEI and PEI were effective in predicting tumor response (AUC = 0.757, p < 0.001; AUC = 0.655, p = 0.005). CONCLUSION: AEI and PEI, parameters from evaluation of CT pre-treatment attenuation of NETLMs, could predict response to TAE treatment.