Cover Caption

About the cover: A, maximum intensity projections of two representative mice each with a xenograft tumor and injected with either ¹¹¹In-labeled specific antibody (top) or ¹¹¹In-labeled nonspecific antibody (bottom) at the posted times (left to right). B, surface plots of these tumor activity profiles as a function of time for specific antibody (left), nonspecific antibody (middle), and merge (right). See the article by Hoppin et al. on page 350 of this issue.