One area of current debate is the role of adjuvant Trastuzumab in patients with node-negative HER2+ cancers with a diameter of 10 mm or less (T1aN0 or T1bN0—TNM 7th edition; Sobin et al, 2009) who are traditionally thought to be at a low risk of recurrence (Banerjee and Smith, 2010). Here, ERBB2 is linked to cancer.