Background: HER2 overexpression has been suggested as a poor prognostic factor in pts with high-risk urothelial carcinoma (UC). Published data note a wide range of HER2 overexpression in UC, with some reports showing <10% of cases and others exhibiting >50% of cases with ≥2+ HER2 expression by immunohistochemistry (IHC). NeuACT (N10-1; NCT01353222) is a phase 2 trial to determine whether DN24-02, an autologous cellular immunotherapy targeting HER2 based on the same platform used for sipuleucel-T, given as adjuvant therapy following surgical resection can prolong survival (Bajorin, et al. ASCO 2012). Here we report preliminary data for HER2 expression on primary tumor and positive lymph node samples from this study. Methods: Trial eligibility criteria include surgical resection of a primary UC, with either ≥pT2 or pN+ staging, and HER2 expression ≥1+ IHC. Surgical specimens are screened for HER2 expression by central pathology laboratory review and HER2 positivity is scored using the Dako HercepTest scoring system. Results: As of August 2012, tumor specimens from 61 pts have been screened for HER2 expression. Of these pts, 49 (80%; 95% CI: 68–89%) had a HER2 expression score of ≥1+ in the primary tumor, with 27 (44%) having ≥2+ score and 3 (5%) having a 3+ score. Twenty-three pts (38%) also had HER2 expression levels evaluated in tumor from involved lymph nodes. A total of 20 (87%; 95% CI: 66–97%) of these pts had a HER2 expression score of ≥1+ in the lymph nodes, with 12 (52%) having a ≥2+ score and 3 (15%) having a 3+ score. Two pts had primary tumor samples that expressed HER2 but were negative for HER2 expression in the lymph nodes submitted for analysis. Conclusions: Although preliminary, a high frequency (≥80%) of HER2 expression score of ≥1+ in primary tumor and lymph node samples was observed. These data highlight the prevalence of HER2 protein expression in high-risk UC. Furthermore, the HER2 expression data are consistent with previously published data in pts with invasive UC. Clinical trial information: NCT01353222.