Clear cell sarcoma like tumor of gastrointestinal tract: Experience of three cases and review of literature

Clear cell sarcoma-like tumor of the gastrointestinal tract (CCSGT) is a rare, aggressive tumor with many histological mimickers. Herein, we have documented our experience of three cases of CCSGT and reviewed the literature. The index cases were identified in male patients in their twenties, one in jejunum and two in the distal colon. Histomorphological examination revealed the characteristic heterogeneous histomorphology with patchy immunohistochemical positivity with S100 protein and negative melanocytic markers. The fluorescence in-situ hybridization test showed translocation of the EWSR1 (22q12) gene in >80% tumor cells. While one of our patients died after 2 years with lung metastasis, the other two patients are still alive on 1.5 years and 3 months follow up, respectively. CCSGT is a rare malignant tumor of the gastrointestinal tract. Although characteristic morphology, use of a judicial panel of immunohistochemical stains, and translocation study for EWSR1 gene can establish the diagnosis, experience in adjuvant therapy is still limited.

Clear cell sarcoma of gastrointestinal tract：clinicopathologic analyses and review of litera-tures / 临床与实验病理学杂志

Purpose To study the clinicopathologic and genetic features of clear cell sarcoma of the gastrointestinal tract. Methods One case of clear cell sarcoma of the gastrointestinal tract was analyzed by histology, immunohistochemistry, fluorescence in situ hy-bridization ( FISH) , with review of relevant literatures. Results A female patient was admitted to the hospital with a history of 1-week abdominal pain. Computed tomography revealed a mass in right hemicolon. A grey-white ulcerated mass was observed in the colon, in-volving the entire thickness of the colon wall extending into the subserosa. Microscopically, medium-size oval or round cells were ar-ranged in sheets and scattered osteoclast-like multinucleated giant cells were also presented. Immunohistochemically, the tumor cells were strongly positive for S-100 protein, but negative for HMB-45, Melan-A, CD117, CD1a and PCK. FISH showed the rearrangement of EWSR1 in 74% of the neoplasm cells. Conclusions Clear cell sarcoma of the gastrointestinal tract is an extraordinarily rare gastro-intestinal neoplasm that shows peculiar histopathological, immunohistochemical, ultrastructural, and genetic features. Whether clear cell sarcoma-like gastrointestinal tumor represents a distinct entity awaits larger series, including cytogenetic or molecular biological in-vestigation.