PERITUMORAL AND NODAL MUCIPHAGES

Three patients who underwent surgery for cancer showed Alcian blue pos itive cells in the sinusoids of the regional lymph nodes and, in one c ase, extensive infiltration in the soft tissues around the tumor. The cells contained variably sized vacuoles that occasionally indented the nuclei, imparting a signet-ringlike appearance. They were interpreted as muciphages based on morphology, reactivity with mucin stains, posi tive immunohistochemical staining for KP-1 and Mac-387, and negative s taining for cytokeratin, S-100, and leukocyte common antigen (LCA). Th e material contained in these cells was Alcian blue positive at pH 2.5 and pH 1, and was strongly periodic acid-Schiff positive after diasta se digestion. Hyaluronidase only slightly reduced the intensity of the Alcian blue stain. These results indicate that the bulk of the materi al was epithelial-type mucin. To our knowledge, this is the first repo rt of muciphages in lymph nodes. Careful attention to morphology and i mmunohistochemical findings is necessary to avoid confusion with metas tatic or infiltrating signer ring or mucinous adenocarcinoma.