Nistor Andreea, Watson Peter H, Pettigrew Norman, Tabiti Karim, Dawson Angelika, Myal Yvonne
Department of Pathology, University of Manitoba, 770 Bannatyne Ave,, Winnipeg, Manitoba R3E 0W3, Canada.
BMC Clin Pathol. 2006 Jan 18;6:2. doi: 10.1186/1472-6890-6-2.
The clinical benefit of determining the status of HER-2/neu amplification in breast cancer patients is well accepted. Although immunohistochemistry (IHC) is the most frequently used method to assess the over-expression of HER-2 protein, fluorescent in-situ hybridization (FISH) is recognized as the "gold standard" for the determining of HER-2/neu status. The greatest discordance between the two methods occurs among breast tumors that receive an indeterminate IHC score of 2+. More recently, a real-time polymerase chain reaction (PCR) assay using the LightCycler(R) has been developed for quantifying HER-2/neu gene amplification. In this study, we evaluated the sensitivity and specificity of a commercially available LightCycler assay as it compares to FISH. To determine whether this assay provides an accurate alternative for the determination of HER-2/neu status, we focused primarily on tumors that were deemed indeterminate or borderline status by IHC.
Thirty-nine breast tumors receiving an IHC score of 2+ were evaluated by both FISH and LightCycler(R) technologies in order to determine whether quantitative real-time PCR provides an accurate alternative for the determination of HER-2/neu status.
We found a high concordance (92%) between FISH and real-time PCR results. We also observed that 10% of these tumors were positive for gene amplification by both FISH and real-time PCR.
The data show that the results obtained for the gene amplification of HER-2/neu by real-time PCR on the LightCycler instrument is comparable to results obtained by FISH. These results therefore suggest that real-time PCR analysis, using the LightCycler, is a viable alternative to FISH for reassessing breast tumors which receive an IHC score of 2+, and that a combined IHC and real-time PCR approach for the determination of HER-2 status in breast cancer patients may be an effective and efficient strategy.
确定乳腺癌患者HER-2/neu扩增状态的临床益处已得到广泛认可。虽然免疫组织化学（IHC）是评估HER-2蛋白过表达最常用的方法，但荧光原位杂交（FISH）被公认为确定HER-2/neu状态的“金标准”。这两种方法之间最大的不一致出现在免疫组化评分为2+的不确定乳腺肿瘤中。最近，一种使用LightCycler®的实时聚合酶链反应（PCR）检测方法已被开发用于定量HER-2/neu基因扩增。在本研究中，我们评估了一种市售LightCycler检测方法与FISH相比的敏感性和特异性。为了确定该检测方法是否能为HER-2/neu状态的测定提供准确的替代方法，我们主要关注免疫组化判定为不确定或临界状态的肿瘤。
对39例免疫组化评分为2+的乳腺肿瘤进行FISH和LightCycler®技术评估，以确定定量实时PCR是否能为HER-2/neu状态的测定提供准确的替代方法。
我们发现FISH和实时PCR结果之间具有高度一致性（92%）。我们还观察到，这些肿瘤中有10%通过FISH和实时PCR检测均显示基因扩增阳性。
数据表明，在LightCycler仪器上通过实时PCR获得的HER-2/neu基因扩增结果与FISH获得的结果相当。因此，这些结果表明，使用LightCycler进行实时PCR分析是重新评估免疫组化评分为2+的乳腺肿瘤的一种可行替代FISH的方法，并且联合免疫组化和实时PCR方法来确定乳腺癌患者的HER-2状态可能是一种有效且高效的策略。
