Oncolor is an association whose mission is to publish and share medical guidelines in oncology. As many scientific information websites built in the early times of the Internet, its website deals with unstructured data that cannot be automatically querried and is getting more and more difficult to maintain over time. The online contents access and the editing process can be improved by using web 2.0 and semantic web technologies, which allow to build collaboratively structured information bases in semantic portals. The work described in this paper aims at reporting a migration from a static HTML website to a semantic wiki in the medical domain. This approach has raised various issues that had to be addressed, such as the introduction of structured data in the unstructured imported guidelines or the linkage of content to external medical resources. An evaluation of the result by final users is also provided, and proposed solutions are discussed.