In the Original Investigation titled “Tumor-Infiltrating Lymphocytes and Associations With Pathological Complete Response and Event-Free Survival in HER2-Positive Early-Stage Breast Cancer Treated With Lapatinib and Trastuzumab: A Secondary Analysis of the NeoALTTO Trial” published online April 30, 2015, in JAMA Oncology (doi:10.1001/jamaoncol.2015.0830), an error appeared in Figures 2B and 2D. In Figure 2B in the panel title, symbol key, and No. at risk, >40% should be replaced by ≥40%. In Figure 2D, in No. at risk, >40% should be replaced by ≥40%. This article was corrected online.