Sclerosing epithelioid fibrosarcoma presenting as intraabdominal sarcomatosis with a novel EWSR1-CREB3L1 gene fusion

• Published in: Human pathology 2014-10, Vol.45 (10), p.2173-2178
• Main Authors: Stockman, David L., MD, Ali, Siraj M., MD, PhD, He, Jie, PhD, Ross, Jeffrey S., MD, Meis, Jeanne M., MD
• Format: Article
• Language: English
• Subjects: Abdominal Neoplasms - genetics; Abdominal Neoplasms - pathology; Adult; CREB3L1; EWSR1; Fibrosarcoma; Fibrosarcoma - genetics; Fibrosarcoma - pathology; Humans; Immunohistochemistry; In Situ Hybridization, Fluorescence; LGFMS; Low-grade fibromyxoid sarcoma; Male; Mesothelioma; Oncogene Proteins, Fusion - genetics; Pathology; Sarcoma - genetics; Sarcoma - pathology; Sclerosing epithelioid fibrosarcoma; Sclerosis; SEF; T(11; 22)
• ISSN: 0046-8177; 1532-8392
• DOI: 10.1016/j.humpath.2014.05.006

Summary We report a case of intraabdominal sclerosing epithelioid fibrosarcoma (SEF) with a t (11;22)(p11.2;q12.2) Ewing sarcoma breakpoint region 1–cAMP-responsive element-binding protein 3–like 1 translocation. A 43-year old man presented with massive ascites and shortness of breath. Imaging studies revealed a large mesenteric-based mass with extensive omental/peritoneal disease. After resection and cytoreductive surgery, the tumor recurred with metastasis to the lungs; the patient is still alive with disease. Histologically, there was a uniform population of epithelioid cells arranged in cords and nests, embedded in a dense collagenous matrix; no areas of low-grade fibromyxoid sarcoma were identified. All immunohistochemical markers were nonreactive. Fluorescence in situ hybridization studies showed rearrangement of Ewing sarcoma breakpoint region 1 . Genomic profiling by clinical grade next-generation sequencing revealed a fusion gene between intron 11 of Ewing sarcoma breakpoint region 1 (22q12.2) and intron 5 of cAMP-responsive element-binding protein 3–like 1 (11p11.2). This is the first report of “pure” or true SEF presenting as intraabdominal sarcomatosis with confirmation of the recently described unique Ewing sarcoma breakpoint region 1–cAMP-responsive element-binding protein 3–like 1 gene fusion in SEF without areas of low-grade fibromyxoid sarcoma.