Objective:To establish a radiomics-based biomarker for predicting pathological response after preoperative neoadjuvant chemoradiotherapy (nCRT) in locally advanced esophageal cancer.Methods:From 2008 to 2018, 112 patients with locally advanced esophageal cancer who received nCRT were enrolled. All patients were treated with preoperative nCRT combined with surgery. Enhanced CT images and clinical information before nCRT were collected. A lesion volume of interest was manually delineated. In total, 670 radiomics features (including tumor intensity, shape and size, texture and wavelet characteristics) were extracted using the pyradiomics package in PYTHON. The stepwise regression combined with the best subset were employed to select the features, and finally the Logistic regression model was adopted to establish the prediction model. The performance of the classifier was evaluated by the area under the ROC curve (AUC). Results:The pathological complete remission (pCR) rate was 58.0%(65/112). 10 radiomics features were included in the final model, The most relevant radiomics feature was the gray feature (the texture information of the image), followed by the shape and voxel intensity-related features. In the training set, the AUC was 0.750 with a sensitivity of 0.711 and a specificity of 0.778, the corresponding values in the testing set were 0.870, 0.757 and 0.900, respectively.Conclusions:Models based on radiomics features from CT images can be utilized to predict the pathological response to nCRT in esophageal cancer. As it is efficient, non-invasive and economic model, it could serve as a promising tool for individualized treatment when validated by further prospective trials in the future.

Objective: To investigate the clinical efficacy and adverse effects of stereotactic body radiotherapy (SBRT) in the treatment of T₂N₀M₀ non-small cell lung cancer (NSCLC) patients. Methods: By retrospectively analyzing the clinical data of 30 inoperable patients with stage T₂N₀M₀ NSCLC treated by SBRT, the overall survival, progression-free survival, cancer-specific survival and adverse effects were determined. Results: The median follow-up was 18.4 months. The 1-, 2-, and 3-year overall survival rates were 92.2%, 92.2% and 80.6%, respectively. The corresponding cause-specific survivals were 95.7%, 95.7% and 83.7%. The progression-free survivals were 70.2%, 54.1% and 40.6%. The local control rates were 100%, 94.4%, and 94.4%. The regional controls were 84.2%, 72.1%, and 54.1%; and distant controls were 84.6%, 72.4% and 64.3%, respectively. Twenty patients (66.7%) developed symptoms of grade 1 radiation-related toxicities: dyspnea, chest pain, fatigue, cough, esophagitis, or pneumonia. Among these, 5 patients suffered grade ≥2 radiation pneumonitis, and one patient experienced grade 4 radiation pneumonitis. Conclusions SBRT was efficient and safe for patients with inoperable T₂N₀M₀ NSCLC, imposing tolerable toxicities.