Which looks like a brain?

Here are three colonic polyps. One is a TA+LGD, another a TA+HGD and the final is a TVA+HGD
WHICH POLYP IS THE TVA?

a) A

Nope, this one has slit-like crypts typical of a tubular adenoma (TA). In fact, most small polyps are TA's. Presumably there is a progression from TA→TVA→Cancer apart from depressed lesions (IIc lesions) which go directly from being TA's to cancer.

b) B

It's a little difficult to see the crypt pattern without a close-up. However, you don't need to! Look at the growth morphology. This is a LST-NG and they are ALWAYS TA's!

c) C

Yes! Gyrate crypts best seen after indigocarmine dye spray (I think).

explanation

Most 'laterally spreading TVA's are of course LST-G's.  However, this doesn't have the usual cobblestoned appearance of a 'laterally spreading tumour of the granular type'.  It's rather 'chunky' in fact. That's because its harbouring HGD!  A rare beast indeed as almost all laterally spreading TVA's only harbour LGD.