Adams Heiner, Schmid Patrik, Dirnhofer Stephan, Tzankov Alexandar
Institute for Pathology, University Hospital Basel, Schoenbeinstrasse 40, 4031 Basel, Switzerland.
Pathol Res Pract. 2008;204(8):569-73. doi: 10.1016/j.prp.2008.02.008. Epub 2008 Apr 23.
Aberrant expression of cytokeratins (CK) is known to occasionally occur in malignant lymphomas. The monoclonal mouse-anti-human CK cocktail CK22 recognizes keratin polypeptides with a wide range of molecular weights and can be applied in diagnostic panels for tumors of unknown origin. Using tissue microarray technology, we tested 1059 lymphoma and acute leukemia cases, covering the most common disease entities, for aberrant CK expression, using CK22. In total, 866 of the arrayed cases were evaluable (80%), and 13 positive cases (1.5%) were found: 1 out of 230 Hodgkin lymphomas (0.4%), 1 plasma cell myeloma, 2 out of 326 diffuse large B-cell lymphomas (0.6%), 5 out of 18 mantle cell lymphomas (26%), 3 out of 70 small cell lymphomas/chronic lymphocytic leukemias (4%) and 1 out of 27 peripheral T-cell lymphomas, not otherwise specified (4%). Immunostaining was finely granular in most cases, and the total amount of positively staining cells exceeded 10% only in the cases of Hodgkin lymphoma and plasmocytoma. All CK22-positive cases, except for one mantle cell lymphoma, expressed the specific simple epithelial CK8 but not the basal/stratified epithelial CK5/6. Aberrant CK expression can be encountered in a small subset of otherwise characteristic B- and T-cell lymphomas, but not in acute leukemias, which should be considered in difficult differential diagnostic settings.
细胞角蛋白（CK）的异常表达偶尔会出现在恶性淋巴瘤中。单克隆小鼠抗人CK混合抗体CK22可识别多种分子量的角蛋白多肽，可用于不明来源肿瘤的诊断。我们采用组织芯片技术，使用CK22检测了1059例淋巴瘤和急性白血病病例，涵盖了最常见的疾病类型，以检测CK的异常表达。总共866例阵列病例可进行评估（80%），发现13例阳性病例（1.5%）：230例霍奇金淋巴瘤中有1例（0.4%），1例浆细胞骨髓瘤，326例弥漫性大B细胞淋巴瘤中有2例（0.6%），18例套细胞淋巴瘤中有5例（26%），70例小细胞淋巴瘤/慢性淋巴细胞白血病中有3例（4%），27例未另行指定的外周T细胞淋巴瘤中有1例（4%）。大多数病例的免疫染色呈细颗粒状，仅在霍奇金淋巴瘤和浆细胞瘤病例中，阳性染色细胞总数超过10%。除1例套细胞淋巴瘤外，所有CK22阳性病例均表达特异性简单上皮CK8，但不表达基底/复层上皮CK5/6。在一些具有特征性的B细胞和T细胞淋巴瘤的小亚组中可出现CK异常表达，但在急性白血病中未出现，在困难的鉴别诊断中应考虑这一点。
