title: Low-grade lymphoma of immature T-cell phenotype in a case of lymphocytic interstitial pneumonia and Sjögren's syndrome.
abstract: A 19-year-old male patient presented with lymphocytic interstitial pneumonia and Sjögren's syndrome, confirmed by histopathology. He was treated with prednisone; 4 months later, cyclophosphamide was added. A lymph node taken at presentation revealed no histological signs of malignancy. Lymph nodes obtained 1 and 2 years later exhibited an effaced structure and a diffuse infiltration of small-sized lymphocytic cells compatible with a low-grade non-Hodgkin's lymphoma. The immunological phenotype of the lymphoma resembled that of immature T-cells present in the normal thymus cortex--positivity for CD1, CD2, CD4, CD7, CD38 and terminal deoxynucleotidyl transferase; faint positivity for CD5 and in the second specimen for CD3; negativity for CD6 and MHC class 1 antigen. The occurrence of such a peculiar lymphoma in Sjögren's syndrome has not been reported thus far. Small numbers of putative malignant cells were found on immunohistochemistry in a lymph node and a lung biopsy obtained at presentation. This is suggestive of one underlying pathogenetic event in the development of lymphocytic interstitial pneumonia, Sjögren's syndrome and non-Hodgkin's lymphoma.
mesh_terms: D000328:Adult; D006801:Humans; D007136:Immunoglobulins / Q000032:analysis; D008168:Lung / Q000473:pathology; D008198:Lymph Nodes / Q000276:immunology / Q000473:pathology / Q000648:ultrastructure; D008223:Lymphoma / Q000150:complications / Q000175:diagnosis / Q000473:pathology*; D008297:Male; D008854:Microscopy, Electron; D011658:Pulmonary Fibrosis / Q000150:complications* / Q000473:pathology; D012859:Sjogren's Syndrome / Q000150:complications* / Q000473:pathology; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000648:ultrastructure
chemical_list: D007136:Immunoglobulins