What is “synovial sarcoma”?
Synovial sarcoma (Synovialsarcoma) is a malignant tumor of the soft tissue that originates from the synovial membrane of the joints, synovial membranes and tendon sheaths. The etiology and origin of the tissue are not known.
It occurs in the large joints of the extremities, but can also occur in the myofascia and fascia of the forearms, thighs, and low back. The main clinical symptoms are mainly local painless masses, and surgical excision is the most important treatment.
What are the clinical manifestations of synovial sarcoma?
Synovial sarcoma occurs in young adults aged 15-40 years old, and often presents as a painless mass near the large joints of the extremities, and patients may develop peri-articular swelling, and the mass may extend along the soft tissue to the whole limb. The duration of the disease varies, mostly 2-4 years, and is generally slow-growing. In the later stages, there may be venous anger and varying degrees of pain on the skin surface of the mass, and a few patients have limited local limb movement.
Synovial sarcoma is a highly malignant tumor that can metastasize to regional lymph nodes as well as to distant lungs.
What are the examination items of synovial sarcoma?
1.X-ray examination
In about 30% of lesions, faint and scattered calcifications can be seen, and sometimes periosteal reactions can be seen, even erosion of bone or invasion into the bone, which only appear as soft tissue masses at first, but later calcifications can appear in the masses.
2.Bone scan
In the late stage of the scan, a limited increase in uptake is seen around the mineralized active area within the lesion. Due to the abundance of neovascularization in the lesion, a higher uptake is seen in the early stage of the scan than in the adjacent soft tissues.
3.CT
CT scan reveals a soft tissue mass with uniform texture and density similar to skeletal muscle. The high degree of calcification within the lesion is suggestive of synovial sarcoma, and the use of contrast can result in significant enhancement of the lesion tissue.
The edge of the mass is enhanced after contrast injection.
4.MRI
Lesions are often adjacent to important neurovascular bundles and show high signal on MRI images. Larger lesions have heterogeneous signal intensity, suggesting areas of hemorrhage and necrosis, so these structures may be displaced or encapsulated in the lesion.
5. Angiography
In the early arterial phase, significant neovascularization is seen in the reaction zone around the lesion, and in the late venous phase, significant staining is seen.
4.How to differentiate and diagnose synovial sarcoma?
Diagnosis.
Synovial sarcoma is usually found near the large joints of the limbs and is a malignant tumor. If the mass occurs around the joints, synovial sarcoma should be considered as a possibility, and local MRI and chest X-ray should be performed to clarify the local scope and systemic condition, and the confirmation of diagnosis relies on pathological biopsy.