Selby W L, Nance K V, Park H K
Department of Pathology and Laboratory Medicine, East Carolina University School of Medicine, Greenville, North Carolina.
Mod Pathol. 1992 Jul;5(4):415-9.
Immunohistochemical techniques may aid in the diagnosis of poorly differentiated metastatic tumors. Anti-carcinoembryonic antigen (CEA) antibodies have been used in the identification of epithelial neoplasms. However, recent unpublished data report CEA reactivity in malignant melanoma and melanoma cell lines. We studied 28 cases of known metastatic malignant melanoma with an antibody panel for CEA (polyclonal and monoclonal), AE1:3, S-100, and HMB-45. Reactivity for CEA (polyclonal) was seen in 15 of 28 (53%) cases: nine exhibited strong diffuse positivity, five moderate focal positivity, and one globular cytoplasmic staining. Focal reactivity for cytokeratin (AE1:3) was seen in three of 28 cases. HMB-45 staining was present in 23 of 28 (82%, including strong positivity in the cytokeratin-reactive cases). Staining for S-100 protein was strong in all cases. No staining was seen for CEA (monoclonal). CEA immunoreactivity is seen in a significant number of metastatic malignant melanoma cases. This may be due to CEA expression by tumor cells, or crossreactivity of the polyclonal antibody with substances such as nonspecific crossreacting antigen (NCA) that share antigenic sites with CEA. These findings emphasize the need for care in interpreting immunohistochemical results. Immunohistochemical evaluation of CEA should not be made alone, but only as part of a diagnostic antibody panel.
免疫组织化学技术可能有助于低分化转移性肿瘤的诊断。抗癌胚抗原（CEA）抗体已用于上皮性肿瘤的鉴定。然而，最近未发表的数据报道了恶性黑色素瘤及黑色素瘤细胞系中有CEA反应性。我们用一组针对CEA（多克隆和单克隆）、AE1:3、S-100和HMB-45的抗体研究了28例已知的转移性恶性黑色素瘤病例。28例中有15例（53%）出现CEA（多克隆）反应性：9例表现为强弥漫性阳性，5例为中度局灶性阳性，1例为球状胞质染色。28例中有3例出现细胞角蛋白（AE1:3）局灶性反应性。28例中有23例（82%，包括细胞角蛋白反应性病例中的强阳性）有HMB-45染色。所有病例中S-100蛋白染色均为强阳性。CEA（单克隆）未见染色。在相当数量的转移性恶性黑色素瘤病例中可见CEA免疫反应性。这可能是由于肿瘤细胞表达CEA，或多克隆抗体与诸如非特异性交叉反应抗原（NCA）等与CEA共享抗原位点的物质发生交叉反应。这些发现强调了解释免疫组织化学结果时需要谨慎。对CEA的免疫组织化学评估不应单独进行，而应仅作为诊断抗体组的一部分。
