Histiocytic sarcoma of the parotid gland region.
ABSTRACT Histiocytic sarcoma (HS) is a malignant neoplasm showing the morphological and immunophenotypic features of mature histiocytes. Reported herein is a case of HS of the parotid gland region. A 53-year-old woman noticed a swelling of the right preauricular area. Preoperative fine needle aspiration cytology showed an admixture of pleomorphic atypical cells and mature lymphocytes. She underwent total parotidectomy. Grossly, the tumor was located at the parotid gland to subcutaneous tissue, and showed infiltrative growth with massive necrosis and hemorrhage. Microscopically, the tumor was composed of marked pleomorphic cells with eosinophilic cytoplasm. Bizarre multinuclear giant cells were scattered and intermingled. Tumor cells were positive for CD68 (KP-1 and PG-M1), CD163, S-100 protein, CD1a, CD4 and CD31, but negative for CD3, CD20, CD21, CD79a, DEC205 and langerin, immunohistochemically. Monoclonal proliferation of B cells was not confirmed on polymerase chain reaction for IgH. The patient had recurrent lesions in the pelvis and stomach 5 months after parotidectomy and died of the disease 10 months after the operation.
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ABSTRACT: Histiocytic sarcoma (HS) is a rare malignant neoplasm that originates from a histiocytic hematopoietic lineage characterized by histiocytic differentiation and its corresponding immunophenotypic features. We herein reported a case of primary HS of the stomach which was confirmed through histopathologic examination and immunohistochemical staining. A 52-year-old woman presented with progressive difficulty in feeding and dull pain in the epigastric region. Gastroscopy, endoscopic ultrasonography, double contrast examination, and computed tomography revealed a mass located on the posterior wall of fundus and lesser curvature of the stomach. Microscopically, the cytoplasm of the tumor cells was abundant and eosinophilic. Immunohistochemical staining revealed that the tumor cells were positive for CD45RO and CD68. It is difficult to differentiate HS of stomach from other gastric malignancies by radiological evaluation alone. However, HS may be considered when a protruding and ulcerated mass in stomach shows heterogeneous hypervascular features. To the best of our knowledge, this is the first report in English language literature that emphasizes the imaging findings of human gastric HS.World Journal of Gastroenterology 01/2013; 19(3):422-425. · 2.47 Impact Factor