涎腺多形性低度恶性腺癌和腺样囊性癌临床病理和免疫组化对比

Clinicopathological and immunohistochemical comparison of polymorphous low-grade adenocarcinoma and adenoid cystic carcinoma of the salivary glands

目的探讨涎腺多形性低度恶性腺癌(polymorphous low-grade adenocarcinoma,PLGA)和腺样囊性癌(adenoid cystic carci-noma,ACC)的鉴别诊断。方法收集10例PLGA和12例对照组ACC,对比观察2组肿瘤的临床和组织学特征,并行c-kit、Galection-3、α-SMA、p63和Ki-67免疫组化染色。结果该组PLGA占同期小涎腺恶性肿瘤的6.9%,肿瘤全部位于口腔内,80%发生在腭部。组织学上呈筛状、管状和实性生长方式,浸润性边缘和嗜神经性为PLGA和ACC所共有,但PLGA瘤细胞形态单一、圆形或立方状,细胞核呈温和的泡状核,排列成多种结构,包括管状、梁状、乳头状、乳头囊状、小叶状,筛状、细索状等,常可见形态一至的单层细胞导管、单排溪流样和靶环状生长方式。免疫组化染色显示5种标记物在PLGA和ACC中均有表达,但表达程度和方式有所不同。结论 PLGA是少见的小涎腺恶性肿瘤,好发于腭部;组织病理学特点是鉴别PLGA和ACC的最可靠标准,温和的细胞形态和高度变异的生长方式是PLGA的特征;c-kit、Galetion-3、α-SMA,、p63均非PLGA或ACC的特异性标记物,只能在支持形态学诊断时作为辅助参考。

Purpose To investigate the differential diagnosis between adenoid cystic carcinoma（ACC） and polymorphous low-grade adenocarcinoma（PLGA）.Methods 10 cases of PLGA and 12 comparison cases of ACC were retrieved,the comparison of the clinical and histological features in two groups of tumor,immunohistochemical staining for c-kit、galection-3、α-SMA、p63 and Ki-67 were performed.Results The total of PLGA accounted for 6.9% of minor salivary gland malignant tumor in the same period,the tumors were all intraoral and 80% occurred in the palate.Histologically,PLGA shared cribriform,tubular and solid patterns,infiltrative borders and neurotropism with ACC.However,tumor cells in PLGA were uniform,round to cuboidal with bland vesicular nuclei,arranged in diverse architectural patterns,including tubular,trabecular,papillary,papillary-cystic,lobular,cribriform,strand-like and so on,the tubules were lined by a single layer of monomorphic tumor cells,single filing of tumor cells and targetoid patterns were usually seen in PLGA.Immunohistochemical staining showed that expression extent and pattern of the five markers were different in the two tumors.Conclusions PLGA is a rare malignant tumor of minor salivary gland with a predilection for the palate;Histopathological features remain the most reliable criteria to distinguish between these two tumours,PLGA is characterized by bland-looking tumour cells and highly variable growth patterns.C-kit、galection-3、α-SMA、p63 does not appear to be an speical marker for ACC or PLGA,and immunohistochemistry may be only used to support morphologic dignosis as an adjunctive method.