Paul M. Cavallaro, M.D. • Caitlin Stafford, B.S. • Christy E. Cauley, M.D. David L. Berger, M.D., M.P.H. • Liliana Bordeianou, M.D., M.P.H. • Hiroko Kunitake, M.D., M.P.H. Todd Francone, M.D., M.P.H. • Rocco Ricciardi, M.D., M.P.H.
In microsatellite unstable cancers, lymphovascular invasion, perineural invasion, and high-grade histology are not associated with worse overall survival, even when deferring adjuvant chemotherapy. These data support National Comprehensive Cancer Network recommendations to forego chemotherapy
in stage II cancers with microsatellite instability and these features. In contrast, some high-risk features were associated with worse survival despite microsatellite unstable biology, and therapies to improve survival need to be explored.