Anaplastic lymphoma kinase-negative uterine inflammatory myofibroblastic tumor containing the ETV6-NTRK3 fusion gene: a case report

• Published in: Journal of international medical research 2018-08, Vol.46 (8), p.3498-3503
• Main Authors: Takahashi, Akimasa, Kurosawa, Manabu, Uemura, Mao, Kitazawa, Jun, Hayashi, Yoshihiko
• Format: Article
• Language: English
• Subjects: Adult; Anaplastic Lymphoma Kinase - genetics; Anaplastic Lymphoma Kinase - metabolism; Case Reports; Female; Humans; Immunohistochemistry; Kinases; Lymphoma; Neoplasms, Muscle Tissue - diagnosis; Neoplasms, Muscle Tissue - genetics; Neoplasms, Muscle Tissue - surgery; Oncogene Proteins, Fusion - genetics; Oncogene Proteins, Fusion - metabolism; Targeted cancer therapy; Uterine Neoplasms - diagnosis; Uterine Neoplasms - genetics; Uterine Neoplasms - surgery
• ISSN: 0300-0605; 1473-2300
• DOI: 10.1177/0300060518780873

Inflammatory myofibroblastic tumors (IMTs) are neoplasms with low malignant potential, and the most common tumor in the lung and orbit. Their occurrence in the uterus is rare. Approximately 50% of IMT patients have anaplastic lymphoma kinase gene (ALK) rearrangements. Recent studies described novel fusions involving ROS1, platelet-derived growth factor receptor beta (PDGFR-β), and ETS translocation variant (ETV6) genes in a subset of ALK-negative patients. We report a 44-year-old woman with anemia and uterine IMT. Ultrasonography and magnetic resonance imaging revealed a myxoid degenerative myoma-like mass, 7.4 cm in maximum diameter, on the left uterine side wall. Hysterectomy was performed as a definitive treatment. Microscopic examination revealed spindle cell proliferation with numerous lymphocytes and plasma cells. Immunohistochemically, the spindle cells were negative for ALK-1, desmin, and smooth muscle actin. The pathological diagnosis was IMT arising from the uterus. Fluorescence in situ hybridization demonstrated an ETV6–neurotrophic tyrosine kinase, receptor, type 3 gene (NTRK3) translocation but no ALK, ROS1, or PDGFR-β translocations. Lung and abdomen computed tomography at 31 months postoperatively revealed no disease recurrence. This association of an ETV6–NTRK3 fusion oncogene with an ALK-negative uterine IMT increases our understanding of this neoplasm, which may help the development of specific therapies.