Desmoplastic small round cell tumor of the pleura with brain metastasis: A case report and literature review

Abstract

Introduction: Desmoplastic small round cell tumor (DSRCT) is a rare and aggressive mesenchymal neoplasm characterized by a chromosomal translocation involving the EWSR1 and WT1 genes. It typically arises in intra-abdominal tissues (i.e., mesentery, omentum, pelvic organs), and commonly spreads to regional lymph nodes, lungs, or liver, while central nervous system (CNS) metastasis is rare. Case Report: We present a unique case of DSRCT originating from the pleura in a young female, which was metastatic to intrathoracic and mediastinal tissue at diagnosis and later spread to the brain. The initial tumor samples exhibited characteristic histopathological features, including small round cells with minimal cytoplasm and indistinct borders embedded in a fibroblastic stroma. Notably, the brain metastasis demonstrated distinct histological characteristics, lacking the desmoplastic stroma observed in previous biopsies. Conclusion: This case underscores the diagnostic challenges associated with DSRCT, emphasizes the significance of early recognition and appropriate histological evaluation, and contributes to the limited literature on the histological features and metastatic behavior of this rare tumor.