One is not more dangerous than the other, as sessile polyps and tubular adenomas are simply different terms relating to the shape and growth pattern of a polyp, explains American Cancer Society. Sessile polyps and sessile tubular adenomas are polyps that have not yet become cancerous.
Sessile is a medical term that means a polyp is slightly flattened and broad-based, states American Cancer Society. A tubular adenoma is a medical term that means a polyp is tubular in shape. Therefore a sessile tubular adenoma has a tubular growth pattern and is slightly flattened and broad-based. A tubular adenoma is generally smaller than a villous adenoma. A large villous adenoma is more likely to develop cancer than a tubular adenoma. Polyps are most often removed during a colonoscopy, before they have time to develop into cancer.