Which type of colonic polyp is considered to have the lowest risk of malignancy?

Hyperplastic polyps are considered to have the lowest risk of malignancy among colonic polyps. These polyps are typically small, benign growths found mainly in the left side of the colon. They arise from an overproduction of normal colonic cells and do not have the same potential for dysplasia or progression to colorectal cancer as certain other types of polyps.

In contrast, villous adenomas are known to have a significant risk of developing into colorectal cancer, especially as they increase in size. Hamartomatous polyps, while generally benign, can be associated with certain syndromes that increase the risk of malignancy, such as Peutz-Jeghers syndrome. Inflammatory polyps may arise in response to conditions like ulcerative colitis and can carry an increased risk of cancer depending on the underlying disease.

Overall, hyperplastic polyps are typically not associated with the precancerous changes seen in adenomatous polyps, making them the safest type in terms of cancer risk.