An Inflammatory Myofibroblastic Sarcoma with CDKN1B Gene Rearrangement: Case Report and Literature Review

Inflammatory Myofibroblastic Tumor (IMT) and Inflammatory Myofibroblastic Sarcoma (IMS) are uncommon in the Head and Neck region. We present a patient (9 yrs old girl) with IMT from a lacrimal system, undertaking a gross total resection at the department of Ophthalmology, followed by corticosteroid therapy and radiotherapy. After cessation of radiotherapy, the tumor recurred rapid growth rate with the expansion into the entire globe, left paranasal sinuses, and the ipsilateral masseter space and parotid gland. The second surgery with resection of all abovementioned infiltrated structures was performed at the department of Head and Neck, and the pathological outcome turns out to be IMS. However, negative margin could not be achieved. Next generation gene sequencing analysis of whole exome was performed, and the abnormality of CDKN1B gene rearrangement was identified. The role of CDKN1B in the pathogenesis of IMS warrants further investigation.