The role of the lymphatic network in colorectal cancer: anatomy, molecular drivers and management.

Abstract

Our understanding of the structures and functions of the lymphatic system in colorectal cancer (CRC) has advanced dramatically in recent years. This review aims to outline the information regarding lymphatic drainage of the colon and rectum, as well as our current knowledge of molecular determinants of lymphangiogenesis (e.g., vascular endothelial growth factor-C/-D) and the evaluation of the clinical significance of lymphatic microvessel density in cancer. The review also addresses controversies and innovations in CRC staging, including the impact of lymphovascular invasion on indications for adjuvant chemotherapy, especially in early-stage cancer. A review of current developments in the surgical treatment of CRC (transanal total mesorectal excision and lateral pelvic lymph node dissection) was also conducted, with special reference to the oncological relevance of lymphatic drainage. Knowledge of the complex structures of the lymphatic network is required to establish an individualized risk assessment, and to select the most appropriate surgical strategy in order to optimize the treatment of patients with CRC.