CD1A and neoplasm: In our cohort, we found a small but statistically significant reduction in the number of in situ CD3+ T cells (mean for tumor negative nodes of 8878 vs. tumor positive nodes of 6704, p = 0.006), but no statistically significant difference in CD20+ B cells or CD1a+ dendritic cells between tumor positive and negative SLNs (Fig. 2a–c).