Hepatic flexure: The end of the beginning, or the beginning of the end? Why pre-operative localisation remains inconsistent.

Abstract

Precision colon cancer surgery increasingly aims to tailor the extent of resection to individual tumour biology and lymphatic drainage, guided by pre-operative assessment. However, at the hepatic flexure (HF), reproducible pre-operative localisation remains challenging because the HF is not a discrete anatomical point but a transition zone. Misclassification at the HF is not merely semantic: given non-trivial intermediate and central nodal metastasis rates in this region, inconsistent localisation may influence assumptions about regional nodal basins and the adequacy of mesenteric excision and lymphadenectomy. We propose mapping the HF as a bounded transition zone defined by two reproducible, pre-operatively appreciable landmarks, rather than an ill-defined 'turn'. This pragmatic framework may better align multidisciplinary planning with true lymphovascular territory and increase the proportion of patients receiving appropriately targeted lymphovascular resection.