Immune cell density according to the pathological response. The vertical axis indicates cell count/mm2, and the horizontal axis indicates the pathological response. Statistically significant P values are shown in bold italics. The numbers of patients are as follows: pCR, N = 23; non-pCR, N = 43. Patients with pCR to neoadjuvant chemotherapy showed a higher density of intratumoral and stromal CD4+ T cells than those with non-pCR (P = 0.036 and 0.031, respectively).