Primary pulmonary synovial sarcoma
Primary pulmonary synovial sarcoma is an extremely rare tumor and refers to a situation where a synovial sarcoma arises from the lung as a primary site. It together with a pleural synovial sarcoma comes under the broader category of pleuro-pulmonary synovial sarcomas .
Epidemiology
It accounts for less than 0.5% of all lung tumors.
Pathology
The diagnosis can only be established only after sarcoma like primary lung malignancies and metastatic sarcoma has been confidently excluded.
Subtypes
There are four recognized pathological subtypes
- monophasic fibrous
- monophasic epithelial
- biphasic
- poorly differentiated
Radiographic features
They can occur anywhere ranging from peripheral to central.
CT
Can occur in variable locations within the lung as described above. Typically seen a "well defined" mass . They can be heterogeneous enhancement post intravenous contrast .
Treatment and prognosis
The overall prognosis for primary pulmonary sarcomas are poor. In many cases a treatment of choice is surgical removal with view to achieve negative resection margins. Completeness of resection (but not size or grade) is thought to be a key factor associated with increased survival.
History and etymology
It was first described in 1995 by Zeren and colleagues as a distinctive primary lung sarcoma, but sharing histological and immunohistochemical features with monophasic synovial sarcomas of soft tissue.