Synovial sarcoma is a highly malignant soft-tissue tumor. It originates from synovial tissues but often goes beyond the capsule in the para-articular soft-tissues.
The tumour occurs mostly in young adults but it has also been found in the adolescents and children.
Knee and hip are most common locations followed by shoulder and elbow. These sites account for 85% of tumor occurence.
The synoviomas are large, bulky and fast-growing and may often be painful at these sites.
About 15 percent of cases synovioma is located in the hands and feet.
In these distal sites the tumors present as small, superficial, soft, fixed masses that grow slowly.
Patient would generally present with a fast growing or slow growing mass depending on the location. On hands and feet the tumour may be painless. Tenderness may be absent.
Regional lymph node examination may reveal metastasis which is not uncommon in this tumor. The involved nodes are hard, fixed, and nontender, and they enlarge rapidly.
A soft-tissue mass may be noted on radiography and may show focal calcification taking place in the tumor tissue.
Scintigraphy with technetium-99m shows increased uptake in the tumor due to microcalcification and revascularization of synovial sarcoma. The zone about the synovium depicts a very active increased reactive uptake. The involved bone and lymph show increased activity.
Computed tomography will depict the soft-tissue tumor and delineate its extent of spread-whether intracompartmental or extra-compartmental.
Angiography is of great value in staging.
In gross appearance, the tumor is a semifirm, somewhat encapsulated lesion that measures from 1 to 4 cm. in diameter.
The histologic findings consist of closely intermingled fibrosarcomatous and synovial components. The cytologic hallmark of synovioma is the primitive or mesenchymal spindle connective tissue cells lining spaces and clefts, which may contain mucin. Occasionally, the cells are more cylindrical and arranged around spaces resembling cells of epithelial origin.
Treatment depends upon the anatomic site and stage of the neoplasm.
- Small tumors in the hands or feet are treated by wide excision. However amputation is the procedure to be taken if the tumour recurs
- The large synovial sarcomas located around arm or thigh are treated by radical excision.
Postoperative radiotherapy may be given for palliation