Adult ; Diagnosis, Differential ; Female ; Histiocytoma, Malignant Fibrous ; immunology ; pathology ; Histiocytosis, Langerhans-Cell ; immunology ; pathology ; Histiocytosis, Sinus ; immunology ; pathology ; Hodgkin Disease ; immunology ; pathology ; Humans ; Ki-1 Antigen ; metabolism ; Lewis X Antigen ; metabolism ; Lung ; immunology ; pathology ; Lung Neoplasms ; immunology ; pathology ; Lymph Nodes ; immunology ; pathology

Immunohistochemical study on 26 cases of Langerhans cell histiocytosis (LCH) using several leukocyte antibodies in addition to traditionally used markers (S-100 protein and peanut agglutinin) revealed that the proliferating cells of LCH expressed UCHL1, MT1 as well as classically known positivity for S-100 protein, HLA-DR and peanut agglutinin but were negative for OPD4. In comparison to S-100 protein peanut agglutinin (PNA) using a two stage method produced weaker staining and positively stained cells were sparse. Also in this study, a small proportion of proliferating cells in LCH was observed to be reactive for both myeloid/macrophage antigens (KPI, MAC 387 and lysozyme) and Langerhans cell marker (S-100 protein), verifying the existence of a hybrid form of histiocytes.
Adolescent ; Adult ; Antigens/*genetics ; Child ; Child, Preschool ; Female ; Histiocytosis, Langerhans-Cell/*immunology/pathology ; Human ; Immunohistochemistry/methods ; Infant ; Male ; Middle Age ; Phenotype ; Staining and Labeling ; Support, Non-U.S. Gov't

We present three cases of concurrent Langerhans cell histiocytosis (LCH) and B-lineage lymphoid cell infiltrations and/or nodules in the bone marrow. The first patient was a 25-month-old boy who presented with LCH on the right shoulder and multiple osteolytic lesions. Bone marrow biopsy showed the presence of LCH and two large lymphoid nodules of B-lineage, which were located in the paratrabecular region. Both LCH and the lymphoid nodules resolved after treatment with prednisone, vinblastine, methotrexate, and cyclophosphamide. The second patient was a 7-month-old girl who presented with LCH in the scalp and bone marrow. In spite of the treatment, a follow-up bone marrow analysis performed after 16 months showed LCH and increased B-lineage lymphoid cells in the interstitial area. The third patient was a 26-month-old girl, and imaging studies revealed reddish skin lesions and multiple osteolytic lesions. Skin biopsy and bone marrow biopsy did not show the presence of LCH; however, we initiated the treatment on the basis of the results of imaging studies. The follow-up study after 6 months showed the presence of LCH and large, patchy infiltration of B-lymphoid cells. We report three rare cases of concurrent bone marrow involvement of LCH and B-lineage lymphoid proliferation, which strongly suggest lymphoid malignancy. Further, clonal changes should be studied to elucidate the common pathogenic mechanism between the two diseases.
Antineoplastic Agents/therapeutic use ; B-Lymphocytes/immunology/*pathology ; Bone Marrow/immunology/*pathology ; Cell Proliferation ; Child ; Child, Preschool ; Cyclophosphamide/therapeutic use ; Drug Therapy, Combination ; Female ; Histiocytosis, Langerhans-Cell/*diagnosis/drug therapy/pathology ; Humans ; Male ; Methotrexate/therapeutic use ; Prednisone/therapeutic use ; Vinblastine/therapeutic use