Comparison of (a) CD1a-expressing cells, (b) CD83-expressing cells, (c) IL-10-expressing cells and (d) IL-12-expressing cells in sentinel lymph nodes (SLNs) of study patients and lymph nodes draining from noncancer-containing breasts (uninvolved lymph nodes) of women with breast cancer. Each data point represents the mean number of cells per high-powered field (in five fields) (magnification, × 400) from a paraffin-embedded section analyzed by immunohistochemistry. The horizontal bars represent the median number for each group. The numbers of CD83-expressing cells or CD1a-expressing cells in SLNs were not different from those in the uninvolved lymph nodes, but a significant difference was seen when expression of IL-10 or IL-12 was examined. Significantly greater numbers of IL-10-expressing and IL-12-expressing cells were seen in the SLNs compared with the uninvolved lymph nodes (P = 0.02 and P = 0.002, respectively).