Synovial Sarcoma : Immunostains BCL2

Comments:
Additional immunohistochemical markers expressed in synovial sarcomas include: CD99 (product of MIC2 gene; 60-70% of cases), BCL2 (shown here; expressed in most cases; especially in spindle cells), calponin, calretinin, desmoplakin ZO-1 (specialized cell-junction associated protein), claudin-1, and occludin.

BCL2 immunoreactivity has been noted in several other spindle cell neoplasms such as solitary fibrous tumor, Kaposi sarcoma, and GIST. All of these lesions are CD34+ whereas synovial sarcomas are negative for CD34. Image courtesy of: Evita Sadimin, MD (@ESadimin); used with permission