Inflammatory myofibroblastic tumor in the head and neck-a neoplasm with both tumor features and inflammation

Objective. The aim of this study was to unveil the reciprocal relation of tumor characteristics and inflammation in inflammatory myofibroblastic tumor in the head and neck. Study Design. The study included a retrospective cohort of patients with inflammatory myofibroblastic tumors treated between 2005 and 2017 in a tertiary hospital. Tumor features and inflammation were assessed through the expression of anaplastic lymphoma kinase (ALK), the degree of inflammation and cyclooxygenase-2 (COX-2) expression. The prognostic factors were analyzed for overall survival (OS) and disease-free survival (DFS) in univariate and multivariate analyses. Results. Forty-one patients diagnosed with inflammatory myofibroblastic tumors were followed up, and 41 paraffin sections were obtained. The positive rate of ALK expression was 21 (51.2%) of 41 patients. Nineteen patients had high-grade ALK expression, and 22 patients had low-grade ALK expression. Thirty-nine patients had high-grade inflammation, and 2 had low-grade inflammation. The positive rate of COX-2 expression was 100%. Tumors with both high-grade ALK expression and inflammation had worse DFS (P =.015). The multivariate Cox analysis showed that the grades of ALK expression and inflammation (P =.004) were independent risk factors for DFS. Conclusions. Because of the latent synergistic effects of ALK and inflammation in the tumorigenesis of inflammatory myofibroblastic tumor, the combined therapy of ALK and COX-2 inhibitors shows promise.