ICD-11

A malignant neoplasm characterised by the chromosomal translocation t(X;18)(p11;q11). It can occur at any age, but mainly affects young adults, more commonly males. Although any site can be affected, the vast majority of the cases arise in the deep soft tissues of extremities, especially around the knee. Microscopically, synovial sarcoma is classified as monophasic (with a spindle or epithelial cell component) or biphasic (with both spindle and epithelial cell components). Synovial sarcomas can recur or metastasize to the lungs, bones, and lymph nodes.