ERBB2 and ductal breast carcinoma in situ: Interestingly, DC-based neoadjuvant vaccines that selectively promote the development of strong anti-HER-2 Th1 immunity, defined by CD4 T cell secretion of select cytokines such as IFN-γ and TNF-α, can induce peritumoral accumulation of CD4pos (helper T cells) and CD20pos (B cells) lymphocytes at the site of HER-2pos early breast cancer (ductal carcinoma in situ, DCIS) [2, 3].