Giedl Johannes, Büttner-Herold Maike, Wach Sven, Wullich Bernd, Hartmann Arndt, Agaimy Abbas
Institute of Pathology, Friedrich-Alexander University of Erlangen-Nuremberg, University Hospital, Erlangen, Germany.
Section for Nephropathology, Friedrich-Alexander University of Erlangen-Nuremberg, University Hospital, Erlangen, Germany.
Hum Pathol. 2016 Sep;55:101-7. doi: 10.1016/j.humpath.2016.04.016. Epub 2016 May 14.
Prostate adenocarcinoma and hepatocellular carcinoma (HCC) are common cancer types. Both may present with bone metastases, and both are known to be CK7/CK20 negative. Thus, diagnosis of less well-differentiated tumors at metastatic sites essentially relies on immunohistochemical confirmation. However, insufficient data exist on the expression status of the main 2 hepatocyte markers hepatocyte paraffin 1 (HepPar-1) and arginase-1 (Arg-1) in prostatic adenocarcinoma. We screened 557 prostate carcinoma cases for expression of these 2 markers using tissue microarrays. Sixty-four of 557 (11.5%) cases showed highly variable expression of HepPar-1 in 1% to 75% of tumor cells with a characteristically strong granular "mitochondrial" pattern. Only 13 cases (2.3%) expressed HepPar-1 in greater than 10% of the tumor cells. No correlation was seen with Gleason grade. On the other hand, 19 (3.4%) of 557 cases showed variable nonspecific cytoplasmic expression of Arg-1 distinct from the specific combined nucleocytoplasmic staining seen in normal liver and in HCC. Specifically, this Arg-1 pattern was seen only using one antibody lot and not another suggesting cross-reactivity. Only a single case showed specific nucleocytoplasmic expression of Arg-1 in the tumor cells. In conclusion, specific granular cytoplasmic staining for HepPar-1 is frequent in prostatic adenocarcinomas (11.5%) but usually focal and limited to less than 5% of tumor cells. This should not be misinterpreted as evidence of HCC, particularly in solid-pattern neoplasms. On the other hand, specific Arg-1 expression is very rare (0.18%), highlighting the value of Arg-1 in distinguishing HepPar-1-positive prostatic carcinoma from HCC at metastatic sites or in cases of liver metastasis from prostate carcinoma.
前列腺腺癌和肝细胞癌(HCC)是常见的癌症类型。两者都可能出现骨转移,并且都已知为CK7/CK20阴性。因此,转移性部位低分化肿瘤的诊断主要依赖免疫组化确认。然而,关于前列腺腺癌中两种主要肝细胞标志物肝细胞石蜡1(HepPar-1)和精氨酸酶-1(Arg-1)的表达状态的数据不足。我们使用组织微阵列筛选了557例前列腺癌病例以检测这两种标志物的表达。557例病例中有64例(11.5%)显示HepPar-1在1%至75%的肿瘤细胞中表达高度可变,具有特征性的强颗粒状“线粒体”模式。只有13例(2.3%)在超过10%的肿瘤细胞中表达HepPar-1。与Gleason分级未见相关性。另一方面,557例病例中有19例(3.4%)显示Arg-1的可变非特异性细胞质表达,与正常肝脏和HCC中所见的特异性核质联合染色不同。具体而言,这种Arg-1模式仅在使用一批抗体而非另一批抗体时可见,提示存在交叉反应。仅1例病例在肿瘤细胞中显示Arg-1的特异性核质表达。总之,HepPar-1的特异性颗粒状细胞质染色在前列腺腺癌中很常见(11.5%),但通常为局灶性且限于不到5%的肿瘤细胞。这不应该被误解为HCC的证据,特别是在实性模式的肿瘤中。另一方面,特异性Arg-1表达非常罕见(0.18%),突出了Arg-1在区分转移性部位的HepPar-1阳性前列腺癌或前列腺癌肝转移病例中的HCC方面的价值。