Published online Sep 6, 2019. doi: 10.12998/wjcc.v7.i17.2637
Peer-review started: April 22, 2019
First decision: June 12, 2019
Revised: June 27, 2019
Accepted: July 20, 2019
Article in press: July 20,2019
Published online: September 6, 2019
Calcifying fibrous tumor (CFT) is a rare benign mesenchymal tumor that often occurs in deep soft tissue of children and young adults. CFT rarely occurs in the mediastinum.
In this paper, we describe a 31-year-old male patient with CFT in the mediastinum. The patient did not have any symptoms, and the posterior mediastinal lesion was unintentionally found during routine re-examination of thyroid cancer. The tumor had no adhesion to the surrounding tissue and was successfully and completely removed. Pathology showed a large amount of collagen-rich fibrous connective tissue. There was scattered dystrophic calcification and gravel in the fibrous tissue and a small amount of lymphocyte and plasma cell infiltration and lymphoid follicle formation in the interstitial fluid. In addition, findings showed 20 IgG4+ plasma cells per high-powered field of the diseased tissue, an IgG4+/IgG ratio of about 20%, and normal serum IgG4 levels. The final diagnosis was CFT of the mediastinum (CFTM). No evidence of tumor recurrence was observed by computed tomography at 3 mo after surgery.
IgG4+ plasma cell enlargement may occur in CFTM, but clinical manifestations and serological tests suggest that it is not IgG4-related disease. We speculate that it may be an independent tumor subtype.
Core tip: Calcifying fibrous tumor of the mediastinum (CFTM) is a rare benign mesenchymal tumor that often occurs in children and young adults. Calcifying fibrous tumor rarely occurs in the mediastinum. Histological examination is the most important basis for diagnosis. Surgical resection is currently the primary means of treatment. There are no reports of recurrence of CFTM.