LeBoit P E, Crutcher W A, Shapiro P E
Department of Pathology, University of California, San Francisco 94143-0506.
Am J Surg Pathol. 1992 Jun;16(6):584-92. doi: 10.1097/00000478-199206000-00006.
Pagetoid intraepidermal spread of neoplastic cells was noted in six cases of Merkel (primary neuroendocrine) cell carcinoma of the skin. In two cases, the volume of the intraepidermal portion of the neoplasm was either equal to or more extensive than the dermal component. The intraepidermal component in all six cases was remarkable because of the following findings: the presence of cells with scant cytoplasm arranged both individually and as nests, sometimes along the dermoepidermal junction; splaying of the apical portions of basal keratinocytes by solitary neoplastic cells; incomplete rims of compressed basal keratinocytes at the peripheries of some junctional nests; and occasional contiguity of neuroendocrine carcinoma cells with those of Bowen's disease or solar keratosis. These features can be used to distinguish these Merkel cell carcinomas from other lesions that have a pagetoid pattern, even in superficial biopsies, and immunohistochemistry can confirm the diagnosis or resolve problematic cases. The occurrence of cutaneous neuroendocrine carcinoma situated largely in the epidermis raises the possibility that some of these tumors may arise from intraepidermal Merkel cells.
在6例皮肤默克尔（原发性神经内分泌）细胞癌中发现肿瘤细胞呈派杰样表皮内播散。2例中，肿瘤的表皮内部分体积等于或大于真皮成分。所有6例的表皮内成分都很显著，原因如下：存在胞质稀少的细胞，这些细胞既单个存在，也呈巢状排列，有时沿着真皮表皮交界处分布；单个肿瘤细胞使基底角质形成细胞的顶端部分展开；一些交界性巢周边的基底角质形成细胞有压缩形成的不完整边缘；神经内分泌癌细胞偶尔与鲍温病或日光性角化病的细胞相邻。这些特征可用于将这些默克尔细胞癌与其他具有派杰样模式的病变区分开来，即使在浅表活检中也是如此，免疫组织化学可确诊或解决疑难病例。主要位于表皮的皮肤神经内分泌癌的发生增加了这些肿瘤中一些可能起源于表皮内默克尔细胞的可能性。
