Astekar Madhusudan, Metgud Rashmi, Sharma Priyanka, Ramesh Gayatri
Department of Oral and Maxillofacial Pathology, Pacific Dental College and Hospital, Debari, Udaipur (Rajasthan), India.
Clin Pract. 2012 Jan 30;2(1):e17. doi: 10.4081/cp.2012.e17. eCollection 2012 Jan 1.
Rhabdomyosarcomas are among the most common soft-tissue tumors in children. These tumors are derived from mesenchymal tissue with a tendency toward myogenic differentiation that probably originates from immature and highly invasive satellite cells associated with the embryogenesis of skeletal muscle. Some of these tumors are associated with high rates of recurrence and metastasis. The diagnosis is made by microscopic analysis and auxiliary techniques such as immunohistochemistry, electron microscopy, cytogenetic analysis, and molecular biology. We report a case of 28-year-old man who presented with a painless progressive swelling of gingiva since 3 months, which was gradually increasing in size without any systemic symptoms or signs of any metastatic spread. An incisional biopsy was done and histopathology reported an alveolar variant of rhabdomyosarcoma. Immunohistochemistry with panel of markers was done which showed positivity for CD99, vimentin and negative for desmin and myogenin. So the characteristic immunohistological expression was negative in present case. Hence we conclude that haematoxylin and eosin morphology and ultrastructure are needed to classify rhabdomyosarcoma and immunohistochemistry act only as an auxiliary.
横纹肌肉瘤是儿童最常见的软组织肿瘤之一。这些肿瘤起源于间充质组织，具有向肌源性分化的倾向，可能起源于与骨骼肌胚胎发生相关的未成熟且具有高度侵袭性的卫星细胞。其中一些肿瘤具有较高的复发率和转移率。诊断通过显微镜分析以及免疫组织化学、电子显微镜、细胞遗传学分析和分子生物学等辅助技术进行。我们报告一例28岁男性患者，自3个月以来出现牙龈无痛性进行性肿胀，肿块大小逐渐增大，无任何全身症状或转移扩散迹象。进行了切开活检，组织病理学报告为横纹肌肉瘤的腺泡型。进行了一组标志物的免疫组织化学检测，结果显示CD99、波形蛋白呈阳性，结蛋白和肌生成素呈阴性。所以本例的特征性免疫组织学表达为阴性。因此我们得出结论，横纹肌肉瘤的分类需要苏木精和伊红染色形态学及超微结构检查，免疫组织化学仅起辅助作用。
