Imaging features for diffuse-type tenosynovial giant cell tumor of the temporomandibular joint

Abstract

Rationale:The tenosynovial giant cell tumor (TGCT) is a benign but locally aggressive tumor that arises from the synovial membrane of joints, tendon sheaths, and bursae. Although any joint can be affected, involvement of the temporomandibular joint (TMJ) was reported very rarely, and there is no relevant report on 18F-FDG PET/computerized tomography (CT).Patient concerns and diagnoses:We present here a rare case of diffuse-type of TGCT (D-TGCT) arising from the right TMJ in a 74-year-old woman. The patient was discovered a mass of the right temporal fossa during a head CT scan. However, she did not receive any treatment and was discharged from the hospital. She visited our institution again after 4 years with worsening headache and swelling of the right preauricular area. An enhanced CT demonstrated a 6.0 × 3.4 × 5.0 cm mass of mixed density involving the right TMJ, with evident enhancement and extensive erosion of adjacent bones. Magnetic resonance imaging (MRI) showed hypointensity in the solid part of the mass but high signal intensity in the cystic part or necrosis on T2-weighted images (T2WI). In 18F-FDG PET/CT images, the solid portion of the mass had increased FDG uptake with a SUVmax of 19.8. It was then diagnosed as D-TGCT by postoperative pathology.Lessons:The case report shows the imaging features of the TGCT, including CT, MRI, and 18F-FDG PET/CT, especially the typical hypointensity on T2WI. Careful preoperative examination and complete resection are the factors that lead to the optimal treatment of the TGCT.

Recurrent pigmented villonodular synovitis of the temporomandibular joint

“…PVNS involving the TMJ is a rare entity and is difficult to diagnose clinically. The reported incidence is 1.8 annual cases per million individuals in which most lesions affect the knee, hip, or shoulder [1] . Patients usually present in the third and fourth decades with symptoms of TMJ dysfunction [2] .…”

“…The etiology of this disease process is unclear, with histopathology characterized by hyperplasia of the synovium in joints and tendinous sheaths. There is accentuated proliferation of the stroma cells, and a significant quantity of intracellular and extracellular hemosiderotic pigments, as well as accumulation in multinucleated giant cells [1] , [3] . It should be noted that giant cell tumors of the tendon sheath are considered synonymous with PVNS microscopically [4] .…”

Diffuse giant cell tumors of the tendon sheath in temporomandibular joint

“…[ 6 ] The localized form of GCT-TS is most prevalent and generally follows an indolent course, frequently affecting the tendon sheath and joints of the hands. [ 7 ] In contrast, diffuse-type GCT-TS are less common and typically affect the knee, hip, or shoulder. The knee is commonly involved in 80% of cases, but any joint may be affected.…”

Organized hematoma of temporomandibular joint

“…Still, this feature might also be suitable for describing tumors showing internal hemorrhage signal such as vascular malformation or giant cell tumors. 11 12 Compared with vascular malformation and giant cell tumors, organized hematoma showed hypointense peripheral rim indicating fibrous capsule around the mass. 9 In addition, giant cell tumors occurred in this region showed more aggressive expansion involving cranial base or condyle head destruction compared to the organized hematoma.…”

“… 9 In addition, giant cell tumors occurred in this region showed more aggressive expansion involving cranial base or condyle head destruction compared to the organized hematoma. 12 …”