Cold-forceps avulsion with adjuvant snare-tip soft coagulation (CAST) is an effective and safe strategy for the management of non-lifting large laterally spreading colonic lesions.

Background And Aims: Non-lifting large laterally spreading colorectal lesions (LSLs) are challenging to resect endoscopically and often necessitate surgery. A safe, simple technique to treat non-lifting LSLs endoscopically with robust long-term outcomes has not been described.

Methods: In this single-center prospective observational study of consecutive patients referred for endoscopic mucosal resection (EMR) of LSLs ≥ 20 mm, LSLs not completely resectable by snare because of non-lifting underwent standardized completion of resection with cold-forceps avulsion and adjuvant snare-tip soft coagulation (CAST). Scheduled surveillance colonoscopies were performed at 4 - 6 months (SC1) and 18 months (SC2). Primary outcomes were endoscopic evidence of adenoma clearance and avoidance of surgery. The secondary outcome was safety.

Results: From January 2012 to October 2016, 540 lifting LSLs (82.2 %) underwent complete snare excision at EMR. CAST was required for complete removal in 101 non-lifting LSLs (17.8 %): 63 naïve non-lifting lesions (NNLs; 62.7 %) and 38 previously attempted non-lifting lesions (PANLs; 37.3 %). PANLs were smaller ( < 0.001) and more likely to be non-granular ( = 0.001) than the lifting LSLs. NNLs were of similar size ( = 0.77) and morphology ( = 0.10) to the lifting LSLs. CAST was successful in all cases and adverse events were comparable to lifting LSLs resected by complete snare excision. Recurrence at SC1 was comparable for PANLs (15.2 %) and lifting LSLs (15.3 %;  = 0.99), whereas NNLs recurred more frequently (27.5 %;  = 0.049); however, surgery was no more common for either type of non-lifting LSL than for lifting LSLs.

Conclusion: CAST is a safe, effective, and surgery-sparing therapy for the majority of non-lifting LSLs. It is easy to use, inexpensive, and does not require additional equipment.