title: Intraocular inflammatory myofibroblastic tumor with ALK overexpression.
abstract: We report a case of an intraocular inflammatory myofibroblastic tumor nearly filling the vitreous cavity of the eye of a 50-year-old man. The tumor was composed of a mixture of spindle cells and mixed inflammatory elements, including numerous plasma cells. The differential diagnosis included inflammatory pseudotumor and neoplastic mimics of this condition. Further investigation with immunohistochemistry revealed the mass to be composed of myofibroblasts, positive for smooth muscle actin stains and with weak anaplastic lymphoma kinase (ALK) expression in some tumor cells. Evaluation by fluorescence in situ hybridization revealed the tumor cells to have multiple copies of chromosome 2 and ALK but no rearrangement of the ALK gene. The authors propose that multiple copies of the ALK gene may be involved in inflammatory myofibroblastic tumor tumorigenesis, in addition to ALK gene rearrangements.
authors.affiliation: Division of Hematopathology, Department of Pathology & Laboratory Medicine, Indiana University School of Medicine, Indianapolis 46202, USA. dpomalle@iupui.edu
authors.forename: Dennis P
authors.initials: DP
authors.lastname: O'Malley
authors.forename: Christopher
authors.initials: C
authors.lastname: Poulos
authors.forename: Magdalena
authors.initials: M
authors.lastname: Czader
authors.forename: Warren G
authors.initials: WG
authors.lastname: Sanger
authors.forename: Attilio
authors.initials: A
authors.lastname: Orazi
mesh_terms: D000077548:Anaplastic Lymphoma Kinase; D005134:Eye Neoplasms / Q000175:diagnosis / Q000201:enzymology / Q000473:pathology*; D005347:Fibroblasts / Q000473:pathology*; D006104:Granuloma, Plasma Cell / Q000175:diagnosis / Q000201:enzymology / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009130:Muscle, Smooth / Q000166:cytology; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D020794:Receptor Protein-Tyrosine Kinases
chemical_list: C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases