Two Faces of Greater Omentum.

The greater omentum, often described as a "plaster" of the abdominal cavity, exhibits remarkable regenerative and immunological properties. Its unique morphology-rich vasculature and a diverse cellular composition comprising adipocytes, endothelial cells, and leukocyte aggregates known as milky spots (MS)-facilitates immune surveillance, fluid uptake, and the secretion of neurotransmitters. Additionally, MS contribute to peritoneal immunity by capturing pathogens, promoting lymphocyte proliferation, and releasing cytokines and chemokines that recruit effector immune cells while limiting local inflammation. Structurally, this peritoneal extension shields visceral organs, prevents adhesions, and absorbs tumor secretions, yet paradoxically also provides a niche for metastatic spread. Moreover, the greater omentum is susceptible to various pathologies-vascular steal can deprive organs of blood, torsion and herniation threaten tissue viability, and ossification can transform the greater omentum into a rigid structure lacking protective properties. Notably, omentectomy has been associated with weakened antibacterial defense, underscoring its protective role. This review aims to explore the multifaceted nature of the greater omentum, emphasizing both its physiological benefits and the potential disadvantages associated with its alteration or removal.