Mikhaleva L M, Vandysheva R A, Shakhpazyan N K, Fedorov E D, Biryukov A E, Midiber K Yu, Pechnikova V V
Research Institute of Human Morphology, Moscow, Russia; City Clinical Hospital Thirty-One, Moscow Healthcare Department, Moscow, Russia.
City Clinical Hospital Thirty-One, Moscow Healthcare Department, Moscow, Russia.
Arkh Patol. 2019;81(2):10-17. doi: 10.17116/patol20198102110.
In the course of the serrated pathway of carcinogenesis, there are changes in the expression of mucins with a characteristic immunophenotypic sign, such as a late loss of intestinal differentiation and an increase in gastric differentiation.
To comparatively assess the expression of Muc 2, Muc 5AC, and Muc 6 in hyperplastic polyps (HPs), sessile serrated adenomas (SSAs) and traditional serrated adenomas (TSAs) of the colon for determination of their role in differential diagnosis.
Sixty-five serrated masses from 52 patients were examined. Among them, there were 26 SSAs, 26 HPs, and 13 TSAs. A histological examination was done using hematoxylin and eosin staining; periodic acid-Schiff reaction in combination with alcian blue, as well as immunohistochemistry with anti-Muc 2, anti-Muc 5AC, and anti-Muc 6 antibodies were used. Genetic testing of the specimens for KRAS and BRAF mutations was also carried out.
All the serrated neoplasms of the colon exhibited a pronounced expression of Muc 2. A marked Muc 6 expression in the dilated crypt bases was found in 76.9% of SSAs, while no reaction was seen in 92.3% of HPs and in 100% of TSAs. SSAs were characterized by an intense Muc 5AC expression in the whole length of the crypts and in the surface epithelium in contrast with HPs and TSAs, where the expression of the marker was focal. Comparison of the response of the markers and the presence of gene mutations identified that the SSAs with BRAF mutation intensely expressed along the length of the crypt for Muc 5AC and Muc 6; and the TSAs with KRAS mutation had a moderate focal Muc 5AC expression in the crypt bases in 100% of cases.
For differential diagnosis of the types of serrated adenomas of the colon, it is useful for a pathologist to apply the immunohistochemical markers Muc 2, Muc 5AC, and Muc 6 in his/her practice.
在锯齿状癌变途径中,黏蛋白的表达会发生变化,具有特征性免疫表型特征,如肠化生后期丧失和胃化生增加。
比较评估结肠增生性息肉(HP)、无蒂锯齿状腺瘤(SSA)和传统锯齿状腺瘤(TSA)中Muc 2、Muc 5AC和Muc 6的表达,以确定它们在鉴别诊断中的作用。
检查了52例患者的65个锯齿状肿物。其中,有26个SSA、26个HP和13个TSA。采用苏木精和伊红染色进行组织学检查;使用高碘酸 - 希夫反应联合阿尔辛蓝,以及抗Muc 2、抗Muc 5AC和抗Muc 6抗体进行免疫组织化学检查。还对标本进行了KRAS和BRAF基因突变的基因检测。
所有结肠锯齿状肿瘤均表现出明显的Muc 2表达。在76.9%的SSA中,扩张的隐窝底部发现明显的Muc 6表达,而在92.3%的HP和100%的TSA中未见反应。与HP和TSA相比,SSA的特征是在隐窝全长和表面上皮中强烈表达Muc 5AC,而HP和TSA中该标志物的表达是局灶性的。标志物反应与基因突变存在情况的比较表明,BRAF突变的SSA在隐窝全长中强烈表达Muc 5AC和Muc 6;100%的KRAS突变TSA在隐窝底部有中度局灶性Muc 5AC表达。
对于结肠锯齿状腺瘤类型的鉴别诊断,病理学家在实践中应用免疫组织化学标志物Muc 2、Muc 5AC和Muc 6是有用的。