%0 Journal Article %T Clear Cell Sarcoma-Like Tumor of the Gastrointestinal Tract, Presenting as a Second Malignancy after Childhood Hepatoblastoma %A Khin Thway %A Ian Judson %A Cyril Fisher %J Case Reports in Medicine %D 2014 %I Hindawi Publishing Corporation %R 10.1155/2014/984369 %X Clear cell sarcoma-like tumor of the gastrointestinal tract (CCSLGT) is a rare malignant neoplasm arising within the wall of the small bowel, stomach, or large bowel, predominantly in children and young adults. It is an aggressive tumor with a high rate of local recurrence, metastases, and early death from disease. Histologically, it is composed of relatively monomorphic ovoid or round cells with clear to eosinophilic cytoplasm, arranged in sheets and sometimes papillary or alveolar architectures, often with CD68-positive osteoclast-like giant cells in variable numbers, and is associated with EWSR1-CREB1 gene fusions. Its pathogenesis is unknown, and histologically it can be easily confused with a variety of intra-abdominal neoplasms. We describe a case of CCSLGT with molecular characterization, presenting as an acutely obstructing small bowel mass in a 33-year-old male, which occurred as a second malignant neoplasm 20 years after treatment with surgery, radiotherapy, and cisplatin and doxorubicin chemotherapy for childhood hepatoblastoma. This gives further insight into the clinical setting of this highly aggressive neoplasm and highlights the use of radiation therapy as a possible etiologic factor. 1. Introduction Clear cell sarcoma-like tumor of the gastrointestinal tract (CCSLGT) is a rare malignant neoplasm arising within the wall of the small bowel, stomach, or large bowel, predominantly in children and young adults. It is associated with high rates of local recurrence, metastasis, and early deaths from disease. Histologically it consists of relatively monomorphic ovoid or epithelioid cells with clear to eosinophilic cytoplasm arranged in sheets and papillary or alveolar architectures, with variable numbers of CD68-positive osteoclast-like giant cells. Because of the nonspecific immunoprofile of focal S100 protein expression and general lack of immunoreactivity to other antibodies, it may be misdiagnosed as a variety of neoplasms, including melanoma, malignant peripheral nerve sheath tumor, or gastrointestinal stromal tumor (GIST). We describe a case arising in the small bowel wall and harboring EWSR1-CREB1 gene fusion by reverse transcription polymerase chain reaction, which occurred in a 33-year-old male who had previously had surgery, irradiation, and chemotherapy for childhood hepatoblastoma. This expands the clinical spectrum of this highly aggressive neoplasm and highlights the possibility of radiation therapy as a predisposing cause. 2. Case History A 33-year-old Caucasian male presented to the Emergency Department of his local hospital %U http://www.hindawi.com/journals/crim/2014/984369/