Anderson C, Krutchkoff D, Pedersen C, Cartun R, Berman M
Department of Surgical Pathology, Hartford Hospital, Connecticut.
Mod Pathol. 1990 Jan;3(1):76-82.
Retrospective review of seven cases of polymorphous low grade adenocarcinoma (PLGA) revealed that the original histologic diagnosis in five instances was mixed tumor (four benign and one malignant). Comparison of PLGA tumors with eleven representative cases of benign pleomorphic adenoma of minor salivary gland (BPA) showed marked similarity in cytologic features. PLGA and BPA also exhibited similar mucohyaline and/or fibromyxoid stromal components. In contrast, tumor margins of the two neoplasms were quite different; margins of PLGA were consistently infiltrative, whereas those of BPA were generally well circumscribed and encapsulated. Immunophenotypic comparison confirmed the glial fibrillary acidic protein (GFAP) positivity in BPA reported by others, whereas cases of PLGA were uniformly nonreactive with this antibody. Although previous reports have emphasized the histologic similarities of PLGA and adenoid cystic carcinoma, our findings indicate that differentiation of PLGA from BPA may represent a more common diagnostic problem. Awareness of comparative histologic features is important in the differential diagnosis of these minor salivary gland neoplasms. Also, monoclonal GFAP may be useful in distinguishing cases of PLGA from BPA where histologic features are otherwise similar.
对7例多形性低度恶性腺癌（PLGA）的回顾性研究显示，5例最初的组织学诊断为混合瘤（4例良性，1例恶性）。将PLGA肿瘤与11例小涎腺良性多形性腺瘤（BPA）的代表性病例进行比较，发现细胞学特征有明显相似性。PLGA和BPA还表现出相似的黏液透明和/或纤维黏液样间质成分。相比之下，这两种肿瘤的边缘有很大差异；PLGA的边缘始终呈浸润性，而BPA的边缘通常界限清楚且有包膜。免疫表型比较证实了其他人报道的BPA中胶质纤维酸性蛋白（GFAP）呈阳性，而PLGA病例对该抗体均无反应。尽管先前的报道强调了PLGA与腺样囊性癌的组织学相似性，但我们的研究结果表明，PLGA与BPA的鉴别可能是一个更常见的诊断问题。了解比较组织学特征对于这些小涎腺肿瘤的鉴别诊断很重要。此外，单克隆GFAP在组织学特征相似的情况下，可能有助于区分PLGA和BPA病例。
