Evidence for colorectal sarcomatoid carcinoma arising from tubulovillous adenoma

Figure 1 Colonoscopy demonstrates. A: Large sessile polypoid growth with velvety surface and superficial ulceration in the rectum (forward view); B: Multilobulated, smooth surfaced exophytic nature of the tumor upon retroflexion. Sonographic images at rectal EUS showing; C: An infiltrative mass with invasion of the muscularis mucosa (star); D: An 8-mm hypoechoic lymph node suspicious for lymphatic metastasis (arrow).