Two types of milk spots are mainly composed of macrophages, lymphocytes, mast cells, monocytes, plasma cells, eosinophils, reticular cells and stromal cells; vessel, lymph vessel and adipocyte can be observed in type ⅱ milky spots. 两型乳斑均主要有巨噬细胞、淋巴细胞、肥大细胞、单核细胞、浆细胞、嗜酸性粒细胞、网状细胞和基质细胞构成;Ⅱ型乳斑内还可见到血管、淋巴管和脂肪细胞。