Sethi, BhawnaPai, TruptiAllam, AbhishekEpari, Sridhar2016-01-182016-01-182015-10Sethi Bhawna, Pai Trupti, Allam Abhishek, Epari Sridhar. Anaplastic lymphoma kinase-positive pulmonary inflammatory myofibroblastic tumor with sarcomatous morphology and distant metastases: An unusual histomorphology and behavior. Indian Journal of Pathology & Microbiology. 2015 Oct-Dec 58(4): 509-512.http://imsear.searo.who.int/handle/123456789/170510Inflammatory myofibroblastic tumor (IMT), an intermediate-grade neoplasm of myofibroblastic/fibroblastic differentiation, occurs commonly in children and young adults. It is characterized by anaplastic lymphoma kinase (ALK) gene rearrangement and overexpression of ALK-protein. However, aggressive behavior is more commonly associated with ALK-negativity rather than ALKpositivity. Pulmonary involvement is most common visceral location and carries minimal potential for distant metastasis. We present a case of 49-year-old female with pulmonary IMT of spindle cell sarcomatous histomorphology. Frequent mitoses and necrosis with characteristic cytoplasmic immunoreactivity for ALK-1 protein and ALK-gene rearrangement on fluorescence in-situ hybridization were noted. This case is unusual for occurrence in higher age-group of fifth decade, sarcomatous histomorphology at presentation (rather than transformation) and metastases to distant sites despite ALK-protein overexpression and gene rearrangement.enAnaplastic lymphoma kinase geneanaplastic lymphoma kinase-proteincrizotinibfluorescence in-situ hybridizationinflammatory myofibroblastic sarcomaArticle