Center for Breast Cancer, National Cancer Center, 111 Jeongbalsan-ro, Ilsan-donggu, Goyang-si, Gyeonggi-do 410-769, Republic of Korea.
Breast Cancer Res Treat. 2010 Aug;123(1):125-8. doi: 10.1007/s10549-009-0627-3. Epub 2009 Nov 15.
It is not known whether the HER2 status of malignant CSF cells coincides with that of the original breast carcinoma cells. We investigated whether CSF cytology specimens were suitable to evaluate HER2 status by fluorescence in situ hybridization (FISH) in patient with leptomeningeal metastasis (LM). Both formalin-fixed paraffin-embedded (FFPE) breast cancer tissue and liquid based CSF cytology specimens were evaluated for HER2 status in 16 patients with LM. We evaluated HER2 gene amplification using FISH on destained CSF cytology slides containing a minimum of 20 malignant cells per slide, and compared these with the HER2 status by immunohistochemistry (IHC) or FISH in FFPE tissues. HER2 was considered positive when the HER2:CEP17 ratio was >or=2.0 or IHC 3+. Of 16 cases, four were HER2 positive and 12 were HER2 negative by FISH analysis in CSF cytology. All CSF-positive cases were HER2 positive by IHC in FFPE tissue. Of 12 HER2 FISH-negative cases in CSF cytology, 10 were HER2 negative (IHC 0 or 1+) and two were IHC 2+ in FFPE tissue. Two IHC 2+ cases had HER2:CEP17 ratios of 1.27 and 2.1, respectively, by FISH in FFPE tissue. As a result, the HER2 status concordance rate between metastatic breast cancer cells in CSF and FFPE primary tissue by IHC and FISH was very high. When CSF cytology specimens were appropriately prepared and had adequate cellularity without dry artifacts, the CSF cytology was suitable to evaluate HER2 status by FISH analysis in patients with LM.
尚不清楚恶性 CSF 细胞的 HER2 状态是否与原发性乳腺癌细胞的 HER2 状态一致。我们通过荧光原位杂交（FISH）检测了 CSF 细胞学标本是否适合评估脑膜转移（LM）患者的 HER2 状态。对 16 例 LM 患者的 CSF 细胞学标本和福尔马林固定石蜡包埋（FFPE）乳腺癌组织进行了 HER2 状态评估。我们使用 FISH 评估了脱染 CSF 细胞学载玻片上至少 20 个恶性细胞中 HER2 基因的扩增情况，并将其与 FFPE 组织中 HER2 状态的免疫组化（IHC）或 FISH 进行了比较。当 HER2：CEP17 比值>或=2.0 或 IHC 3+时，HER2 被认为是阳性。在 16 例病例中，4 例 CSF 细胞学检测 HER2 阳性，12 例 CSF 细胞学检测 HER2 阴性。所有 CSF 阳性病例的 FFPE 组织 IHC 均为阳性。在 CSF 细胞学中，12 例 HER2 FISH 阴性病例中，10 例为 HER2 阴性（IHC 0 或 1+），2 例为 IHC 2+。FFPE 组织中的 2 例 IHC 2+病例的 HER2：CEP17 比值分别为 1.27 和 2.1。因此，通过 IHC 和 FISH，转移性乳腺癌细胞在 CSF 中的 HER2 状态与 FFPE 原发性组织的一致性非常高。当 CSF 细胞学标本经过适当的准备并有足够的细胞数量且没有干燥伪影时，CSF 细胞学标本适合通过 FISH 分析评估 LM 患者的 HER2 状态。
