Development and validation of a nomogram for preoperative prediction of lymph node metastasis in pathological T1 esophageal squamous cell carcinoma oleh Ling Chen, MD, Kaiming Peng, MA, Ziyan Han, MA, Shaobin Yu, MA, Zhixin Huang, MA, Hui Xu, MA, Mingqiang Kang, MD, PHD, Jorddy Neves Cruz.