Background: To determine the feasibility of radiomic analysis for predicting the therapeutic response of gastric carcinoma with peritoneal cavity metastasis (GCPCM) to pulsed low dose rate radiotherapy (PLDRT) using contrast-enhanced computed tomography (CECT) images.
Methods: Pretreatment CECT images of 43 GCPCM patients were analyzed. Patients with complete response (CR) and partial response (PR) were considered responders, while stable disease (SD) and progressive disease (PD) as non-responders. Image features were quantified from tumor region. The capability of each feature on treatment response classification was assessed using Kruskal-Wallis test and receiver operating characteristic (ROC) analysis. Moreover, artificial neural network (ANN) and k-nearest neighbor (KNN) predictive models were constructed based on the training set and the testing set validated the reliability of the models. Comparison between the performances of the models was performed by using McNemar’s test.
Results: The analyses showed that six features (1 first order-based, 1 texture-based, 1 LoG-based, and 3 wavelet-based) were significantly different between responders and non-responders (AUCs range from 0.686 to 0.728). Both two prediction models based on features extracted from CECT showed potential in predicting the treatment response with higher accuracies (ANN: 0.714, KNN: 0.749 for the training set; ANN: 0.816, KNN: 0.816 for the testing set). No statistical difference was observed in the performance of the two classifiers (P = 0.999).
Conclusions: Pretreatment radiomic analysis using CECT can potentially provide important information regarding the therapeutic response to PLDRT for GCPCM, improving risk stratification.