CD68 and malignant conjunctival melanoma: For this purpose, we analyzed Ki-67 as a proliferation marker [16], CD68 as an myeloid cell marker [17], α-SMA as a marker for perivascular cells, myofibroblasts and smooth muscle cells [18, 19] and granzyme B, which is expressed in cytotoxic T cells [20] in the healthy conjunctiva and in conjunctival melanoma (Fig. 3).