Colonoscopy is one of the best methods for screening colon cancer and still is the gold standard despite advancements in the field of virtual endoscopy based on computer-tomographic imaging. As the automatic detection of polyps in endoscopic images is a challenging task for image processing, a variety of research groups have proposed methods that try to fulfill this task to develop a system which supports the doctors during examination. However, the problem can still not be assumed to be solved. This paper provides a review of the state of the art in detection methods published within the last decade. We found out that the major drawback of many approaches is the lack of representative video data, which hinders comparison and evaluation of the published methods.