Type:
Educational Exhibit
Keywords:
Multidisciplinary cancer care, Molecular, genomics and proteomics, Cancer, Radiation therapy / Oncology, Molecular imaging, Diagnostic procedure, PET-CT, MR, CT, Soft tissues / Skin, Musculoskeletal soft tissue, Bones
Authors:
R. Vadapalli1, A. mandava2, H. V. K r1, R. M. S. V. Vadapalli1, V. Koppula1; 1Hyderabad/IN, 2Hyderabad, Telangana/IN
DOI:
10.26044/ecr2019/C-1381
Background
Synovial sarcoma is a rare soft tissue neoplasm commonly found in the lower extremity.
It is included in the differential diagnosis of all soft tissue masses of the foot and ankle.
It has a particular predilection for lower extremity
Rad Mantras To remember
Synovial sarcoma is a rare soft tissue neoplasm commonly found in the lower extremity.
It is included in the differential diagnosis of all soft tissue masses of the foot and ankle.
It has a particular predilection for lower extremity
Synovial sarcoma is the most common malignant soft tissue tumor in the lower extremity,
followed by epithelioid sarcoma and malignant fibrous histiocytoma
Triple sign: Approximately one-third of lesions demonstrate a triple-signal-intensity pattern (High,
intermediate and low ) on T2-weighted images.
The pattern is related to mixtures of hyperintense fluid with or without fluid levels,
an intermediate signal intensity similar to that of fat,
and a slightly hypointense signal intensity similar to that of fibrous tissue.
Calcifications are not easily seen on MR imaging,
and they are usually hypointense on images obtained with all sequences
The pathologic diagnosis is based on the histologic exam with the aid of special staining techniques.
Vimentin stains intermediate filaments and are typically positive in synovial sarcoma.
BCL-2 is an apoptosis gene and is positive in many neoplasms.
EMA and Cytokeratin 5/6 are epithelial markers and are usually positive in synovial sarcoma.
S-100 is a marker of neural differentiation and can be positive or negative in synovial sarcoma.on for the lower extremity.
Synovial sarcomas have two main histologic types,
monophasic fibrous and biphasic.
The monophasic type has a fibrous appearance on the histologic exam with spindle-shaped cells and is commonly positive for S-100.
The biphasic type is composed of more cuboidal or columnar epithelial cells and is usually negative for S-100
MRI is useful for evaluating the extent of the tumor and its involvement with adjacent soft-tissue structures.
For instance,
MRI is helpful in the differentiation of tumor from muscle tissue and in depicting the involvement of neurovascular structures,
tendons,
fascial/fat planes,
and bone marrow.
MRI is also helpful for the differentiation of recurrent soft-tissue tumors from postsurgical or post-irradiation changes.