A lymph node interdigitating reticulum cell sarcoma.

A 20-year-old woman presented with bilateral cervical, supraclavicular, and mediastinal lymphadenopathy. A nodal biopsy specimen showed a diffuse malignant proliferation of large pleomorphic cells. The ultrastructural features and the antigen phenotype (expression of HLA-DR, CD68, alpha 1-antichymotrypsin, and S100 protein and inconstant reactivity for CD11c, CD15, and peanut agglutinin) were consistent with a derivation from interdigitating reticulum cells. Despite intensive combination chemotherapy with autologous bone marrow transplantation and local irradiation, the patient relapsed in the initial sites of the disease. A review of 12 previous reports of interdigitating reticulum cell sarcomas showed that most of these rare tumors behaved aggressively and were unresponsive to classic intensive chemotherapeutic regimens.