Notably, the clinical response for DCIS patients correlated with immune response in the sentinel lymph node, but not peripheral blood, with a significantly increased vaccine-induced CD4+ Th1 response in the sentinel lymph node and trend to lower CD4+ and CD8+ T-cell responses in the peripheral blood.36 These results suggest the need for further investigation into the impact of neoadjuvant vaccination strategies on T-cell activation within intact regional lymph nodes to enhance the antitumor response and improve clinical efficacy of cancer vaccines. Here, CD4 is linked to ductal breast carcinoma in situ.