There are several types of polyps, hyperplastic which are very rarely cancerous, tubular adenoma or adenomatous polyp which can become cancerou; villous adenoma or tubulovillous adenoma which have a high likelihood of developing into cancer if not removed; sessile polyps, and serrated edge polyps. When the polyp is removed it is sent for microscopic examination. Sometimes a polyp may look normal on the outside but have a small foci of precancerous or cancerous cells in the middle. If your MD thought the polyp was obviously problemmatic, he/she would have mentioned a likelihood of cancer. Since nothing was said, your polyp was probably normal but needed to be examined to make sure.