Defined as an adenoma that contains carcinoma which invades the submucosa, but does not extend into the muscularis propria.
Malignant colonic polyps comprise about 11% of all endoscopically removed polyps.
Large polyps than those with villous features are more likely to be malignant.
These polyps do not require surgery if the polyp can be removed completely by endoscopy and has a favorable histology.
Colectomy for polyps is an option because for patients with sessile polyps, since 10% have a risk of lymph node metastases.
For malignant polyps with unfavorable histology or positive resection margin operative management is recommended with standard guidelines for colon cancer surgery and the removal of at least 12 regional lymph nodes.
Because surgical resection today can be accomplished with laparoscopic techniques there is an increase in surgical management of malignant polyps.
Patients who undergo surgery are more likely to be female, have villous tumors, right-sided tumors, and high grade lesions.