ERBB2 and neoplasm: After stratification of whole-mouse imaging data using the 9 mm2 cutoff, mice had on average one WT HER2 tumor, seven d16 HER2 tumors and 5.5 p95 HER2 tumors that were smaller than 9 mm2 (screen-detectable, unpalpable) and 0.09 WT HER2 tumors, 0.8 d16 tumors and 1.5 p95 tumors that were larger than 9 mm2 (large, palpable) (Fig. 2H,I).