Musings on the theory that variation in cancer risk among tissues can be explained by the number of divisions of normal stem cells

This manuscript has been written to address questions related to our recent publication (Science 347:78-81, 2015). We appreciate the many reactions to this paper that have been communicated to us, either privately or publicly. The following addresses several of the most important statistical and technical issues related to our analysis and conclusions. Our responses to non-technical questions are available at http://www.hopkinsmedicine.org/news/media/releases/bad_luck_of_random_mutations_plays_predominant_role_in_cancer_study_shows