Endoscopic resection of colorectal granular cell tumors

Figure 1 Preoperative examination. A: A 0.8 cm submucosal lesion was observed 60 cm from the anal verge (ascending colon). The mass was sessile, the mucosal surface was smooth, with non-necrotic erosion, and was non-circumferential. B: Ultrasonographic examination revealed a 0.5 cm hypoechoic submucosal lesion without muscularis propria involvement.

Figure 2 Endoscopic submucosal dissection procedure. A: A 1.0 cm × 1.2 cm hemispherical submucosal lesion which had a hard texture, fixed, smooth surface, was observed in the ileocecal junction; B: Saline solution with a small amount of epinephrine and indigo carmine was injected beneath the lesion, and resulted in good elevation; C: Complete dissection of the lesion after circumferential incision; D: The lesion was completely removed without any bleeding or perforation; E: Purse-string suture with metallic clips and endoloop; F: Dissected specimen was sent for pathologic examination.

Figure 3 Pathologic findings. A: Infiltrative growth pattern of colorectal granular cell tumor (× 400); B: Tumor cells were strongly positive for cytoplasmic S-100 protein (+++) (× 400).