As Kay suggests, you can usually submit literature reviews as conference abstracts. That said, the more 'scientific' the conference, the less likely that they are to be accepted. I review for several scientific conference committees. I do have to confess that if I review two equal quality abstract submissions; one being a review and the other being primary findings - then I will choose the primary study. Another way to increase the chance of a review submission, is to submit as structured a review as you can i.e. integrative review, systematic review, concept analysis, discourse analysis etc.