The Clinical and Radiological Characteristics of Inflammatory Myofibroblastic Tumor Occurring at Unusual Sites

Abstract

Inflammatory myofibroblastic tumor (IMT) can occur rarely in the soft tissue or joint of the limb. We retrospectively collected IMT cases of these rare sites and analyzed their clinical and imaging appearance. Thirteen cases of IMT were clinically diagnosed and underwent surgical procedures, pathological analyses, and postsurgical follow-up in our two hospitals. Other than one case of IMT of the bladder wall that presented with gross hematuria, none presented with local swelling, fever, or weakness. All the cases of IMT occurring at the bone showed destruction and parosteal soft tissue masses. The boundaries between the mass and normal bone were vague, without calcifications or any periosteal reaction. Five cases of IMF showed continuous enhancement on CT; seven cases demonstrated iso- or hyposignal intensity on T1WI; one case showed hypersignal intensity on T1WI, and eight cases demonstrated a hypersignal intensity signal on T2WI. All the masses located in soft tissues showed clear and sharp boundaries with different sizes of the swelling regions surrounding muscle interspaces. Three cases showed homogeneous enhancement, one case demonstrated heterogeneous enhancement, and two cases showed edge enhancement on enhanced MRI scans. On pathology, all the lesions showed an absence of a pseudocapsule, and four cases of ALK were positive. The radiological manifestations of IMT located at the soft tissue and bones were similar to benign tumors in shape; however, peritumoral edema, parosteal soft tissue, and the invasive rim of IMT are similar to the features of malignant tumors. Different radiological methods should be used to obtain an accurate diagnosis.

Relationship Between Periosteal Reaction and Medial Compartment Knee Osteoarthritis in Observation of Chinese Patients: A Retrospective Single-Centre Comparative Study

“…Some authors have proven that there could be a wide variety of reasons induce periosteal bone formation, including trauma, infection, metabolic diseases, in ammatory disorders, systemic diseases, benign and malignant tumors [6][7][8][9]. At mean time, during the occurrence and progression of medial compartment KOA, we found a general phenomenon that the development of periosteal reaction is often occurred in lateral of proximal tibia diaphysis according to the standing anteroposterior (AP) radiographs.…”

Rare presentation of inflammatory pseudotumour involving subcutaneous tissues with superficial fat sparing

“…2,11 Radiographically, inflammatory pseudotumours are nonspecific, featuring variable degrees of locations and attenuation that can present as distinct masses or infiltrative tissue possibly due to the fluctuating degrees of fibrosis, cellular infiltration and dynamic change during the inflammatory process. 7,[13][14][15][16] When imaged FDG, there is uptake similar to malignancy due to the infiltrating inflammatory cell composition. 17,18 Contrast-enhanced CT may show a homogeneous or heterogeneous lesion with low, equal or high attenuation compared with the surrounding tissue.…”

Inflammatory myofibroblastic tumor arising from soft tissues of extremities harboring a novel CLIP2‐ALK fusion

“…IMT occurs in any anatomical part of the body. However, it rarely occurs in the soft tissues of the extremities, with no more than 20 cases reported, among which the thigh is the most common place, [2][3][4][5] followed by hand, 3,6 foot, 3 articular fossa, 7 and arm. 8 The age of IMT arising from the soft tissue of the extremities is widely distributed, ranging from 6 months to 61 years old.…”

“…7 Two cases with recurrent IMT were located in thigh and groin regions, respectively. 4 Surgical resection is considered to be an efficacious treatment for majority of IMT patients, whether in the extremities or other parts of the body. However, for inoperable cases, ALK inhibitor, crizotinib, is an effective treatment for IMT patients with ALK or ROS1 rearrangement.…”