Synovial sarcoma

Read more about this disease, some with Classification – Types – Signs and symptoms – Genetics – Pathophysiology – Diagnosis – Screening – Prevention – Treatment and management – Cures and much more, some including pictures and video when available.

A synovial sarcoma is a rare form of cancer which usually occurs near to the joints of the arm or leg. It is one of the soft tissue sarcomas.

The cells of a synovial sarcoma have a microscopic appearance similar to that of the synovium, giving the disease its name, but the actual cells from which the tumour develops are unknown and not necessarily synovial. [1]

Primary synovial sarcomas are most common in the soft tissue near the large joints of the arm and leg but have been documented in most human tissues and organs, including the brain, prostate and heart.

Synovial sarcoma occurs most commonly in the young, representing about 8% of all soft tissue sarcomas[2] but about 15-20% of cases in adolescents and young adults.[3] The peak of incidence is before the 30th birthday and males are affected more often than females (ratio around 1.2:1).[2]

Two cell types can be seen microscopically in synovial sarcoma. One fibrous type, known as a spindle or sarcomatous cell, is relatively small and uniform and found in sheets. The other is epithelial in appearance. Classical synovial sarcoma has a biphasic appearance with both types present. Synovial sarcoma can also appear to be poorly differentiated or to be monophasic fibrous, consisting only of sheets of spindle cells. Some authorities[1] state that, extremely rarely, there can be a monophasic epithelial form which causes difficulty in differential diagnosis.

Like other soft tissue sarcomas, there is no universal grading system for reporting histopathology results.[4] In Europe, the Trojani or French system is gaining in popularity[5] while the NCI grading system is more common in the United States. The Trojani system scores the sample, depending on tumour differentiation, mitotic index, and tumour necrosis, between 0 and 6 and then converts this into a grade of between 1 and 3, with 1 representing a less aggressive tumour.[4] The NCI system is also a three grade one but takes account of a number of other factors.

Most, and perhaps all, cases of synovial sarcoma are associated with a reciprocal translocation t(x;18)(p11.2;q11.2). There is some debate about whether the molecular observation itself is definitional of synovial sarcoma.[6]

[tubepress mode=’tag’, tagValue=’Synovial sarcoma’]