recent items display - caching technique?

Question

We have an ASP.NET application in which on the master page we have a user control that displays the most recently accessed entities by the user. To prevent database trips for every page load, we have enabled the caching for this user control by setting the outputcache directive as follows:

<%@ OutputCache Duration="1200" Shared="true" VaryByCustom="SystemUserGUID" VaryByParam="none" %>

My question is - how do you mark the cache as dirty when some other CRUD operation is performed by this user on another entity and so the recent items list should display this new entity at the top of that list?

Thanks, Pratik