Tarakji Bassel, Kujan Omar, Nassani Mohammad Z
Department of Oral Pathology, Faculty of Dentistry, University of Aleppo, Aleppo, Syria.
J Cancer Epidemiol. 2010;2010:250606. doi: 10.1155/2010/250606. Epub 2010 Dec 28.
Context. Immunohistochemical stains for p53 are used as a diagnostic marker associated with malignancy in several histologic types of salivary gland tumors. This marker may be useful in differentiating pleomorphic adenoma (PA) from carcinoma ex pleomorphic adenoma (CPA), as these tumors are often difficult to distinguish on the basis of morphology alone. Objective. to evaluate whatever inactivation of tumor suppressor gene (p53) increases with the tumor progression from normal salivary tissue to PA and eventually CPA. Design. Paraffin blocks of 29 cases of PA, which were surrounded by normal parotid gland, and 27 cases of carcinoma ex pleomorphic adenoma were retrieved and validated. In all cases of carcinoma ex pleomorphic adenoma, a PA "ghost" was identified, and the malignant element was either undifferentiated carcinoma or adenocarcinoma. Results. The results showed negative nuclear expression of P53 in normal parotid gland. Nuclear P53 was expressed strongly in 6/29 (20.7%) pleomorphic salivary adenoma and 10/27 (37%) carcinoma ex pleomorphic adenoma. Conclusion. Our data suggest that inactivation of p53 may play an important role in the evolution of pleomorphic salivary adenoma and carcinoma ex pleomorphic adenoma.
背景。p53免疫组化染色在多种组织学类型的涎腺肿瘤中用作与恶性肿瘤相关的诊断标志物。该标志物在鉴别多形性腺瘤（PA）和多形性腺瘤恶变（CPA）时可能有用，因为这些肿瘤通常仅根据形态学难以区分。目的。评估肿瘤抑制基因（p53）失活是否随肿瘤从正常涎腺组织发展为多形性腺瘤并最终发展为多形性腺瘤恶变而增加。设计。检索并验证了29例被正常腮腺组织包绕的多形性腺瘤石蜡块以及27例多形性腺瘤恶变病例。在所有多形性腺瘤恶变病例中，均识别出一个多形性腺瘤“残影”，恶性成分要么是未分化癌，要么是腺癌。结果。结果显示正常腮腺组织中P53呈阴性核表达。核P53在6/29（20.7%）的多形性腺瘤和10/27（37%）的多形性腺瘤恶变中呈强表达。结论。我们的数据表明，p53失活可能在多形性腺瘤和多形性腺瘤恶变的演变中起重要作用。
