ERBB2 and breast cancer: The goal was to compare the 5‐year DFS and 5‐year OS in patients with early‐stage human epidermal growth factor receptor 2 breast cancer (HER2+ BC) and triple‐negative breast cancer (TNBC) in relation to the amount of stromal tumor‐infiltrating lymphocytes (TILs) after locoregional management by either mastectomy without radiation or lumpectomy and whole‐breast radiotherapy (RT).