Rectal tonsil: A case report and literature review

Figure 1 Colonoscopic finding. A: Endoscopy revealed a hard, a yellow-white, solitary sessile mass (about 5 mm) at 10 cm from the anal verge of the rectum; B: Macroscopic view, after cap-endoscopic mucosal resection.

Figure 2 On endoscopic ultrasound: Well-demarcated, homogeneous hypoechoic solid lesion in the submucosal layer.

Figure 3 Histopathological findings. A: Low-power view of the cap-endoscopic mucosal resection specimen. Hematoxylin and eosin (HE) staining, magnification × 20; B: HE staining, magnification × 40; C: Positive CD20 immunohistochemical staining, magnification × 100; D: Positive CD3 immunohistochemical staining, magnification × 100.