ERBB2 and neoplasm: The median percentage of HER2-positive tumor cells in the virtual biopsy specimens was highest in the oral region and lowest in the anal region [median percentage of HER2-positive cells in the oral region was 34.5 % (range 0–98 %) vs 11.5 % (range 0–91 %) in the central region and 0 % (range 0–98 %) in the anal region; p = 0.027 (oral vs central) and p = 0.020 (oral vs anal)].