title: Inflammatory myofibroblastic tumor of the lung with unique histological pattern and association with Sjögren's disease and systemic lupus erythematosus.
abstract: Inflammatory myofibroblastic tumor (IMT) of the lung is a rare condition. Radiological properties and clinical presentation of this disease can mimic malignant process. We present a case of IMT of the lung in a 58 year old female patient with a single lung nodule. Tumor was unencapsulated, firm, and well circumscribed. Microscopically tumor had multinodular structure with single or multiple small blood vessels in the center of each nodule surrounded in circular pattern by connective tissue containing spindle cells embedded into the thick layers of extracellular matrix. Extracellular matrix was identified as type I and type III collagen fibrils embedded into type IV collagen and laminin. The tumor was surrounded by T-, B-lymphocytes and polyclonal plasma cells. Histological organization of this lesion's stromal component was unique, but cell composition was similar to inflammatory pseudotumor of the lung. In addition, tumor tissue sections exhibited strong positivity for IgG, weak positivity for IgA, 1Cq, but were negative for IgM, and C3. Mutational analysis of the EGFR, KRAS genes and ALK locus rearrangement were performed and did not reveal any mutations. This is the first report of an IMT associated with Sjögren's disease, systemic lupus erythematosus and Non-Hodgkin lymphoma developing in the lungs. Patient was clinically followed up for 18 months and no recurrence of the tumor observed.
authors.affiliation: Department of Pathology and Laboratory Medicine, Harbor-UCLA Medical Center, 1000 West Carson Street, Torrance, CA 90509, USA.
authors.forename: Boris V
authors.initials: BV
authors.lastname: Shlopov
authors.forename: Samuel W
authors.initials: SW
authors.lastname: French
mesh_terms: D015703:Antigens, CD / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism / Q000648:ultrastructure; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007249:Inflammation / Q000150:complications / Q000473:pathology*; D008175:Lung Neoplasms / Q000150:complications* / Q000473:pathology*; D008180:Lupus Erythematosus, Systemic / Q000150:complications* / Q000473:pathology; D008875:Middle Aged; D055613:Multiple Pulmonary Nodules / Q000150:complications / Q000473:pathology; D058628:Myofibroblasts / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D012859:Sjogren's Syndrome / Q000150:complications* / Q000473:pathology; D014746:Vimentin / Q000378:metabolism
chemical_list: D015703:Antigens, CD; D014746:Vimentin