Endoscopic submucosal dissection of a huge esophageal atypical lipomatous tumor (well-differentiated liposarcoma) with a 4-year recurrence-free survival.

A 35-year-old man complained of dull pain after food intake. His medical history and findings from physical examinations and laboratory tests were unremarkable. Standard esophagogastroduodenoscopy revealed a huge mass in the cervical esophagus. On endoscopy, the sausage-like pedunculated tumor protruded into the lumen (▶Fig. 1). Chest computed tomography (CT) scan showed a large mass that was well-circumscribed, intraluminal, and heterogeneous (fatty density in the upper section and parenchymal density in the lower part) (▶Fig. 2). The mass was located between the T1 to T8 levels and connected to the posterior wall of the esophagus. Endoscopic submucosal dissection (ESD) was performed successfully to treat this patient (▶Fig. 3, ▶Video1). The submucosal injection and initial mucosal incision (▶Fig. 3b) were done at the base of the mass, 18 cm from the incisors, using a Hybrid Knife (I-type; Erbe, Tübingen, E-Videos