title: Osteoclast-rich tumor of the gastrointestinal tract with features resembling those of clear cell sarcoma of soft parts.
abstract: Clear cell sarcoma is a high-grade sarcoma with morphological features resembling those of malignant melanoma. An osteoclast-rich tumor of the gastrointestinal tract with features resembling those of clear cell sarcomas of soft parts is very rare. Herein, we report an unusual stomach tumor with microscopic and immunohistochemical characteristics of an osteoclast-rich tumor of the gastrointestinal tract with features resembling those of clear cell sarcomas of soft parts. The tumor cells were predominantly oval, admixed with some round and spindle elements arranged in nests and fascicles, and admixed with scattered osteoclast-like multinucleated giant cells. Neoplastic cells were positive for S-100 protein, and osteoclast-like multinucleated giant cells were immunoreactive to CD68. The unusual morphology of the tumor caused significant diagnostic difficulties. The differential diagnosis included gastrointestinal stromal tumor, primary or metastatic melanoma, and epithelioid malignant peripheral nerve sheath tumor. To the best of our knowledge, this is possibly the second description of an osteoclast-rich tumor of the gastrointestinal tract with features resembling those of clear cell sarcomas of soft parts.
authors.affiliation: Department of Pathology, Jinling Hospital, Clinical School of Medical College, Nanjing University, 305 Zhongshan East Road, 210002 Nanjing Jiangsu, PR China.
authors.forename: Wenbin
authors.initials: W
authors.lastname: Huang
authors.forename: Xinhua
authors.initials: X
authors.lastname: Zhang
authors.forename: Dongjie
authors.initials: D
authors.lastname: Li
authors.forename: Jieyu
authors.initials: J
authors.lastname: Chen
authors.forename: Kui
authors.initials: K
authors.lastname: Meng
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Zengfeng
authors.initials: Z
authors.lastname: Lu
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Zhou
mesh_terms: D000328:Adult; D015703:Antigens, CD / Q000032:analysis; D015214:Antigens, Differentiation, Myelomonocytic / Q000032:analysis; D003937:Diagnosis, Differential; D005770:Gastrointestinal Neoplasms / Q000378:metabolism / Q000473:pathology*; D015726:Giant Cells / Q000737:chemistry / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D010010:Osteoclasts / Q000737:chemistry / Q000473:pathology*; D009418:S100 Proteins / Q000032:analysis; D018227:Sarcoma, Clear Cell / Q000378:metabolism / Q000473:pathology*; D012983:Soft Tissue Neoplasms / Q000378:metabolism / Q000473:pathology*; D000097382:CD68 Molecule
chemical_list: D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D009418:S100 Proteins; C067980:CD68 antigen, human; D000097382:CD68 Molecule