MT-I and MT-II staining of tumor-infiltrating macrophages. Adjacent sections of a DLBCL stained for MT-I and MT-II (A, DAKO-MT × 600) and CD68 (B, PGM1 × 600) showing numerous MT-positive stromal cells with a dendritic morphology (A), similar to the pattern with CD68 (B). In panels C and D, DLBCL with few (C) and abundant (D) numbers of MT-positive tumor-infiltrating macrophages is shown (DAKO-MT × 400). In these cases, only very occasional tumor cells (asterisks in C) are stained with a weak nuclear reactivity.