A shapeshifting polyp!

This polyp was found in the transverse colon. It has not previously been sampled! 
WHAT IS THE LIKELY HISTOLOGY?

■ SSL

INCORRECT as the crypts are slit-like

■ Adenoma with LGD

INCORRECT as the central dip says otherwise

■ Adenoma with HGD

CORRECT!

■ Superficial cancer

INCORRECT because the lesion does lift

explanation

This is a rather interesting polyp. Well its starts off looking rather booring but after the submucosal injection it changes. Rather than a bland looking TA, it appears to be somewhat tethered in it's centre. I suspect that the subtle central dip would have been evident on retroflexion but retroflexion in the ascending proved impossible. Just look at how the scopeguide shows the shaft keeps buckling in the sigmoid and transverse, in spite of abdominal pressure to try to limit its movement. 

With suboptimal lift, you of course have three options: ESD, piecemeal EMR or choosing a more powerful, superstiff (but more dangerous) snare. 

I opted for the latter option (I usually do) and with some difficulty managed to capture the polyp single fragment. Arguably, as this lesion is a 'LST-D' type of lesion a piecemeal resection may have been less appropriate. The LST-D's are usually either HGD/IMca or superficially invasive cancer.  The lift is good, telling you that it's not an invasive cancer after all. 

.  On the other hand, a single fragment ESD may be linked with a 1:20 risk of a microperforation.  In all honesty, probably not any different to the risk of perforation with a superstiff snare!