Primary renal synovial sarcoma: computed tomography imaging findings.

Area of Science:

• Oncology
• Radiology
• Medical Imaging

Background:

• Synovial sarcoma of the kidney is exceptionally rare, with limited data on its imaging characteristics.
• Accurate radiological identification is crucial for timely diagnosis and treatment.

Purpose of the Study:

• To delineate the characteristic computer tomography (CT) findings of primary renal synovial sarcomas (PRSSs).

Main Methods:

• Retrospective analysis of five histopathologically and cytogenetically confirmed PRSS cases.
• Evaluation of unenhanced and multiphase enhanced CT scans for tumor morphology, size, margins, attenuation, and enhancement patterns.

Main Results:

• Tumors presented as solid-cystic masses with well-defined borders, cyst walls, or pseudo-capsules.
• Heterogeneous enhancement with a "rapid wash-in and slow wash-out" pattern was observed in the solid components.
• Renal vein and inferior vena cava thrombus occurred in one case; lymphadenopathy was absent.

Conclusions:

• PRSS should be considered in the differential diagnosis of renal neoplasms in adolescents and young adults.
• Key CT features include solid-cystic appearance, well-defined borders, cystic wall/pseudo-capsule, heterogeneous/septate enhancement, and specific enhancement kinetics.
• Absence of lymphadenopathy is a notable feature.