Distant Invasive Breast Cancer Recurrence Risk in Human Epidermal Growth Factor Receptor 2–Positive T1a and T1b Node-Negative Localized Breast Cancer Diagnosed From 2000 to 2006: A Cohort From an Integrated Health Care Delivery System

Abstract

The distant IR risk of T1a HER2-positive breast cancer appears quite low. The distant IR risk in T1b patients, particularly those with 1.0-cm tumors, is higher. Potential risk differences for T1a and T1b, including the 1.0-cm tumors, should be considered when making treatment decisions.