Inflammatory Myofibroblastic Tumor of the Thigh: Presentation of a Rare Case and Review of the Literature

Table 1

Clinical and pathological features helping differential diagnosis of inflammatory myofibroblasic tumor.

Features that favor IMT	Features that argue against IMT
Child or young adult	Middle aged or older adult
Mass in lung or soft tissue of abdomen, pelvis, and retroperitoneum	Mass of the skin or subcutis, lymph nodes, spleen, or bladder
Diffuse inflammatory infiltrate, prominent plasma cells	Patchy inflammatory infiltrate. Predominantly lymphocytic
Mild nuclear atypia, scattered ganglion-like cells	Moderate to severe nuclear atypia with hyperchromasia
Low mitotic rate, no atypical forms	Atypical mitoses
ALK positivity by immunohistochemistry or ALK gene rearrangement	Necrosis