atypical inflammatory myofibroblastic tumor
References
Inflammatory myofibroblastic tumor: comparison of clinicopathologic, histologic, and immunohistochemical features including ALK expression in atypical and aggressive cases. Coffin CM, Hornick JL, Fletcher CD. Am J Surg Pathol. 2007 Apr;31(4):509-20. PMID: #17414097#