Histological healing: should it be considered as a new outcome for ulcerative colitis?

Introduction: Currently, mucosal healing is considered as a composite treatment end-point in inflammatory bowel disease (IBD) since it has been demonstrated to improve disease-related outcomes. The definition of mucosal healing has evolved and current evidence suggests that in addition to endoscopic healing the achievement of histological remission (HR) represents a potential novel target in the management of IBD in relation to better long-term disease outcomes. Areas covered: We aimed to review the current literature on HR in ulcerative colitis and discuss its limitations and advantages when adopting this potential new target as an ultimate treatment outcome in clinical trials and routine clinical practice. Expert opinion: HR is achievable in UC with different rates in conventional therapies, biological and novel drugs. Targeting HR in UC lowers the risk of hospitalizations, colectomy, and colorectal cancer. HR occurs later than endoscopic remission, longer treatment courses are associated with higher HR assessment. This might imply modifying monitoring time schedules and algorithms. Prospective data are needed to support histological healing as a new treatment target in UC.