Prognostic significance of lymph node-related indices and a novel nomogram for rectal cancer patients with synchronous liver metastases after the preoperative chemoradiotherapy: a population-based study - Xi, Kexing; Wu, Youbo; Sun, Xiaowen; Du, Changzheng; Wang, Feng; Liu, Jialiang; Yin, Yanjiang; Wang, Yutong; Liu, Jiaxiang; Li, Guoxin (Translational Cancer Research, 2026)