Analysis of clinical features and outcomes for inflammatory myofibroblastic tumors in China: 11 years of experience at a single center

Abstract

Purpose: Inflammatory myofibroblastic tumor (IMT) is a rare benign neoplasm. The purpose of this study was to review the clinical characteristics, imaging and pathological features, and outcomes of children with IMTs from a single center in China.

Methods: A retrospective file review was conducted involving 23 cases of pathologically confirmed IMTs treated at the Children's Hospital between April 2003 and April 2014.

Results: The tumor locations included multiple anatomic sites, as follows: abdomen or pelvis (n = 17); lungs (n = 2); head and neck (n = 1); trunk (n = 1); and extremities (n = 2). The tumors were associated with various clinical presentations. The predominant symptoms included an anemic appearance, fevers, and an asymptomatic mass. Computed tomography scanning showed solid, heterogeneous, well-demarcated masses; the appearance of enhancement was variable. MRI appeared hypointense on T1-weighted images and hypointense or hyperintense on T2-weighted images. Immunohistochemical staining revealed anaplastic lymphoma kinase was negative in 11 of 13 cases tested. One patient quit treatment for the unresectable mass after biopsy and died 2 years later, and another patient with incompletely resection is alive at 30 months following chemotherapy. The remaining 21 cases had complete resections; one patient died due to a recurrence, and the other 20 patients survived and were tumor free. The follow-up ranged from 7 to 141 months, with a mean of 56 months. The 3-year OS was 88 % (95 % CI, 57-97 %).

Conclusions: IMT is a benign neoplasm that rarely presents with malignant features. Complete resection is curative in most patients. ALK+ is variable for diagnosis. Close follow-up is necessary for patients who undergo surgical resection.

Keywords: ALK; Follow-up; Inflammatory myofibroblastic tumor; Survival analysis; Treatment.