title: Counterpoint: Adjuvant therapy in stage II colon cancer: pain not justified by the gain.
abstract: No definitive evidence shows benefit from adjuvant therapy for stage II colon cancer, and its role remains controversial. Although a trend toward improved disease-free survival (DFS) has been reported in subgroup analyses from clinical trials that included patients with stage II disease, time trends for recurrences of stage II disease indicate that DFS is not a reliable surrogate for overall survival (OS). Several clinical trials have been conducted to answer the question of whether adjuvant therapy benefits patients with stage II disease, but none have been adequately powered to detect what would be a small OS benefit. Features that are currently used to assign high risk for recurrence (tumor perforation, lymphovascular invasion, <12 lymph nodes analyzed, and poorly differentiated histology) may or may not be associated with clinical outcome, and they are not predictive of treatment benefit. Risks of adjuvant therapy are non-negligible and must be weighed against a large number of patients needed to be treated to realize benefit. Future research should aim to answer the questions of whether microsatellite instability, nodal sampling, molecular markers, and genetic signatures are useful tools to guide decision-making. Given what is now known, the viewpoint is that the aggregate data do not support adjuvant therapy for patients with normal-risk stage II colon cancer.
authors.affiliation: Helen Diller Family Comprehensive Cancer Center, University of California-San Francisco, 1600 Divisadero Street, San Francisco, CA 94115, USA. katherine.vanloon@ucsf.edu
authors.forename: Katherine
authors.initials: K
authors.lastname: Van Loon
authors.forename: Alan P
authors.initials: AP
authors.lastname: Venook
mesh_terms: D003110:Colonic Neoplasms / Q000188:drug therapy*; D006801:Humans; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control*