Granular Mixed Laterally Spreading Tumors: What Is the Risk for Covert Cancer?

Colorectal laterally spreading tumors (LSTs) — defined as nonpolypoid lesions ≥1 cm with lateral growth — can sometimes harbor covert (not endoscopically evident) cancer. LSTs classified by surface morphology as granular have lowest risk for covert cancer, and those classified as nongranular have the highest risk for covert cancer. However, LSTs with granular mixed features (GM-LSTs) have poorly characterized, intermediate risk for covert cancer, leading to uncertainty regarding the optimal resection method.

Now, investigators in Italy have conducted a prospective, multicenter study to determine covert cancer risk in 693 patients (median age, 69 years) with colorectal GM-LSTs without endoscopic features of cancer. Of these patients, three qu…