Errors in Tumor Side and Description of Analysis

In the editorial “Primary Tumor Sidedness as Prognostic and Predictive Biomarker in Metastatic Colorectal Cancer: Further Validation of a Potentially Practice-Changing Variable”¹ published online October 10, 2016, there was an error in describing the prognosis of patients with left-sided vs right-sided primary tumor location. In the first paragraph, the side was inadvertently switched, and in the concluding paragraph it was again switched, saying right when it should have said left, with left-sided, not right-sided, primary tumor location having the better prognosis.

There was also a typographical error in the main body of the article. Where it said “multivariate analysis” it now correctly says “multivariable analysis.” This article has been corrected online.