Department of Anatomic Pathology, Cleveland Clinic, Cleveland, OH, USA.
Am J Surg Pathol. 2011 Apr;35(4):608-14. doi: 10.1097/PAS.0b013e31820bcd2d.
A diagnosis of "atypical glands suspicious for cancer" (ATYP) in prostate needle biopsy is associated with a 40% to 50% risk of finding prostate carcinoma (PCa) in subsequent biopsies. Many studies have attempted to identify clinical, histologic, or molecular characteristics of ATYP that correlated with the risk of PCa in follow-up biopsies. TMPRSS2:ERG gene rearrangement is the most common chromosomal alteration and is highly specific for PCa. Recently, 2 studies reported that positive immunohistochemical (IHC) stains with an ERG antibody highly correlated with the TMPRSS2:ERG gene rearrangement status. We evaluated the use of this antibody as an IHC marker on prostate biopsies with an initial ATYP diagnosis to determine whether positive ERG IHC was associated with increased PCa detection in subsequent biopsies, which therefore might be useful for stratifying ATYP prostate biopsies. ERG IHC was performed on 103 biopsies with initial ATYP diagnosis. Positive ERG IHC staining was detected in 16 of the 103 cases (15.5%) of the ATYP prostate biopsies. Of these 16 ERG-positive cases, the atypical glands were positive for ERG in 9 cases. In the remaining 7 cases, positive ERG staining was found in glands other than ATYP glands, including high-grade prostatic intraepithelial neoplasia and morphologically benign glands. ERG IHC was negative in other benign prostate lesions, including simple atrophy, partial atrophy, proliferative inflammatory atrophy, basal cell hyperplasia, postatrophic hyperplasia, and squamous metaplasia. In subsequent follow-up biopsies, PCa was detected in 7 of the 16 (43.8%) ERG-positive cases and in 42 of the 87 (48.3%) ERG-negative cases (P=0.952 by χ test). In biopsies with ERG-positive ATYP glands, cancer was found in 5 of 9 (55.6%) cases in subsequent biopsies. This is the first study to investigate the use of ERG IHC in difficult prostate biopsies. ERG IHC was positive in a small percentage (15.5%) of the ATYP prostate biopsies, and positive ERG staining did not correlate with the increased cancer detection in subsequent prostate biopsies. Therefore, ERG IHC is not useful for stratifying ATYP prostate biopsies to identify patients who have increased risk for PCa in repeat biopsies. Furthermore, positive ERG staining is not entirely specific for PCa and can occasionally be found in high-grade prostatic intraepithelial neoplasia and benign glands that are not associated with PCa in prostate biopsies.
前列腺针吸活检中诊断为“非典型腺可疑癌（Atyp）”（ATYP）与随后活检中发现前列腺癌（PCa）的风险为 40%至 50%相关。许多研究试图确定与后续活检中 PCa 风险相关的 ATYP 的临床、组织学或分子特征。TMPRSS2:ERG 基因重排是最常见的染色体改变，高度特异性用于诊断 PCa。最近，有 2 项研究报道，用 ERG 抗体进行阳性免疫组织化学（IHC）染色与 TMPRSS2:ERG 基因重排状态高度相关。我们评估了在初始 ATYP 诊断的前列腺活检中使用这种抗体作为 IHC 标志物，以确定 ERG IHC 阳性是否与随后活检中 PCa 检测增加相关，这可能有助于对 ATYP 前列腺活检进行分层。对 103 例初始 ATYP 诊断的活检进行了 ERG IHC。在 103 例 ATYP 前列腺活检中，有 16 例（15.5%）检测到 ERG 阳性 IHC 染色。在这 16 例 ERG 阳性病例中，9 例的非典型腺 ERG 阳性。在其余 7 例中，除了非典型腺外，还发现了 ERG 染色阳性的腺体，包括高级别前列腺上皮内瘤变和形态学良性腺。其他良性前列腺病变，包括单纯萎缩、部分萎缩、增生性炎症萎缩、基底细胞增生、萎缩后增生和鳞状化生，均未见 ERG IHC 阴性。在随后的随访活检中，在 16 例 ERG 阳性病例中的 7 例（43.8%）和 87 例 ERG 阴性病例中的 42 例（48.3%）中发现了 PCa（χ检验，P=0.952）。在 ERG 阳性 ATYP 腺的活检中，在随后的活检中发现 5 例（55.6%）中有癌症。这是第一项研究 ERG IHC 在困难的前列腺活检中的应用。在 ATYP 前列腺活检中，ERG IHC 的阳性率为 15.5%，而阳性 ERG 染色与随后前列腺活检中癌症检出率的增加无关。因此，ERG IHC 对于对 ATYP 前列腺活检进行分层以确定在重复活检中具有更高 PCa 风险的患者并不有用。此外，阳性 ERG 染色并非完全特异性用于 PCa，偶尔也可在高级别前列腺上皮内瘤变和与前列腺活检中不相关的良性腺中发现。
