Published online May 26, 2021. doi: 10.12998/wjcc.v9.i15.3704
Peer-review started: January 7, 2021
First decision: January 24, 2021
Revised: January 25, 2021
Accepted: March 12, 2021
Article in press: March 12, 2021
Published online: May 26, 2021
Processing time: 123 Days and 21 Hours
Giant cell tumor of soft tissue (GCT-ST) is an extremely rare low-grade soft tissue tumor that is originates in superficial tissue and rarely spreads deeper. GCT-ST has unpredictable behavior. It is mainly benign, but may sometimes become aggressive and potentially increase in size within a short period of time.
A 17-year-old man was suspected of having a fracture, based on radiography following left shoulder trauma. One month later, the swelling of the left shoulder continued to increase and the pain was obvious. Computed tomography (CT) revealed a soft tissue mass with strip-like calcifications in the left shoulder. The mass invaded the adjacent humerus and showed an insect-like area of destruction at the edge of the cortical bone of the upper humerus. The marrow cavity of the upper humerus was enlarged, and a soft tissue density was seen in the medullary cavity. Thoracic CT revealed multiple small nodules beneath the pleura of both lungs. A bone scan demonstrated increased activity in the left shoulder joint and proximal humerus. The mass showed mixed moderate hypointensity and hyperintensity on T1-weighted images, and mixed hyperintensity on T2-weighted fat-saturated images. The final diagnosis of GCT-ST was confirmed by pathology.
GCT-STs should be considered in the differential diagnosis of soft tissue tumors and monitored for large increases in size.
Core Tip: Giant cell tumor of soft tissue (GCT-ST) is a rare primary soft tissue tumor that sometimes leads to local recurrence, but rarely to distant metastasis. In this case, the tumor exhibited strip-like calcifications, and the mass destroyed the cortical bone and invaded the bone marrow cavity. Magnetic resonance imaging was performed to establish the extent of the mass. We found multiple small nodules beneath the pleura of both lungs, which we considered as metastases. Development of an aggressive GCT-ST after adolescent trauma is rare. GCT-ST should be considered when interpreting limb masses that involve calcification and bone destruction.