Recent studies including patients with endometrial cancer of diverse histologic type demonstrated HER2 gene amplification in 17/58 (29%) or 11/26 (42%) of uterine serous papillary cancers and 8/63 (13%) grade 3 endometrioid endometrial cancers (Santin et al, 2005; Morrison et al, 2006). The gene discussed is ERBB2; the disease is endometrial cancer.