Kudo SE, Ichimasa K, Villard B, et al. - Researchers applied artificial intelligence to build a model to distinguish T1 colorectal tumors at risk for metastasis to lymph node and confirmed the model in a separate set of patients to reduce unnecessary surgical resections. Data were obtained from 3,134 patients with T1 colorectal cancers (CRC) treated at 6 hospitals in Japan from April 1997 through September 2017 (training cohort). The data revealed that the artificial neural network model outperformed guidelines in distinguishing individuals with T1 CRCs who had lymph node metastases. This model might be applied to ascertain which individuals need additional surgery after endoscopic resection of T1 CRCs.