Acantholytic squamous cell carcinoma (ASCC) is an uncommon variant of squamous cell carcinoma (SCC). It is characterized by a combination of typical SCC and pseudoglandular structures, dyskeratotic cells and prominent acantholysis.

The purpose of this study was to analyze the histochemical and immunohistochemical characteristics of the intraoral variant of ASCC. Cases of intraoral ASCC were retrieved from the English language literature. Four new cases from our files were added.

In total, 35 cases were included and analyzed in this study. The mean age of the patients was 61.5 + 13 years (age range 38–92 years), with a male-to-female ratio of 1.7:1. According to the available data, histochemical and immunohistochemical stains for mucins were found to be consistently negative. E- cadherin, a marker of adherens junctions, was usually reported to be expressed in areas of “typical” (non acantholytic) SCC, but reduced in the acantholytic areas. We examined for the first time the expression of claudin 1, a marker of tight junctions, and found it to be reduced in the acantholytic areas, similar to E-cadherin. Several cases of oral ASCC also expressed vimentin and cytokeratin (CK) 19, markers associated with epithelial-mesenchymal transition. A wide range of non-epithelial markers yielded negative immunoreactions.

In conclusion, ASCC is an uncommon variant of squamous cell carcinoma. The acantholytic process appears to involve reduced expression of molecular components of both adherens junctions and tight junctions. These findings could suggest a relation to the epithelial mesenchymal transition process and therefore further studies are needed in order to establish such a link and the subsequent possible impact on the clinical outcome of the patients.

棘层鳞癌（ASCC）是鳞状细胞癌（SCC）的罕见变体。它的特征在于典型的SCC和伪腺结构，角化异常细胞和显着的棘皮松解症。

这项研究的目的是分析ASCC口腔内变体的组织化学和免疫组化特征。从英语文献中检索出口内ASCC病例。从我们的文件中添加了四个新案例。

本研究共纳入35例病例并进行了分析。患者的平均年龄为61.5 + 13岁（年龄范围38-92岁），男女之比为1.7：1。根据可获得的数据，发现粘蛋白的组织化学和免疫组织化学染色始终为阴性。据报道，E-钙粘着蛋白是粘附连接的标志，通常在“典型”（非棘皮分解）SCC区域表达，但在棘皮分解区域表达减少。我们首次检查了紧密连接的标志物claudin 1的表达，发现其在棘皮层区域减少，类似于E-cadherin。口服ASCC的几例也表达波形蛋白和细胞角蛋白（CK）19，这是与上皮-间质转化相关的标志物。多种非上皮标记物产生阴性免疫反应。

总之，ASCC是鳞状细胞癌的罕见变体。棘皮分解过程似乎涉及粘附连接和紧密连接的分子成分的减少的表达。这些发现可能暗示与上皮间充质转化过程有关，因此需要进一步研究以建立这种联系以及随后对患者临床结果的可能影响。