Beaty M W, Zhuang Z, Park W S, Emmert-Buck M R, Linehan W M, Lubensky I A, Abati A
Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
Cancer. 1997 Jun 25;81(3):180-6.
The differential diagnosis of metastatic clear cell carcinoma is broad. To date, there are no specific immunohistochemical markers for renal cell carcinoma (RCC) in general use. Loss of heterozygosity (LOH) at 3p25.5, the von Hippel-Lindau (VHL) gene locus, is frequent in sporadic clear cell RCC. The authors compared LOH in primary and metastatic RCC through microdissection and the polymerase chain reaction (PCR) to evaluate these techniques as potential diagnostic tools.
The authors identified 14 patients with known clear cell RCC who underwent fine-needle aspiration (FNA) evaluation of presumed metastatic lesion. Direct-visualization microdissection was performed from archival histologic glass slides of the primary neoplasm and the adjacent normal kidney parenchyma. Malignant cell clusters were microdissected from archival FNA slides of metastatic lesions. The cytology slides were previously stained with either Diff-Quik or Papanicolaou stain. This was followed by a single-step DNA extraction and PCR amplification for evaluation of LOH using polymorphic markers, D3S1038 and D3S1110, flanking the VHL gene.
Thirteen of the 14 cases contained DNA suitable for PCR in both the paraffin embedded and the FNA material. Eight of the 13 cases were heterozygous (informative) for the above markers, and 6 of these showed identical allelic loss in the primary and metastatic tumor for either one or both of the markers used. The remaining two cases did not show LOH at the VHL locus with the two polymorphic markers used.
DNA from archival cytologic material stained with Papanicolaou stain or Diff-Quik is reliable for PCR amplification. Visually directed microdissection in combination with PCR has the potential to be a useful technique for confirmatory identification and diagnosis of metastatic clear cell RCC in cytologic material, because a specific genetic abnormality is present in the primary tumor. As characteristic genetic abnormalities are identified in various neoplasms, the use of this technique has the potential for conclusive evaluation of metastatic disease with FNA material, when used in comparison with surgical or cytologic material from the primary tumor. The utility of this combination of techniques has the potential for the molecular diagnosis of morphologically ambiguous cell populations.
转移性透明细胞癌的鉴别诊断范围广泛。迄今为止，尚无普遍应用的肾细胞癌（RCC）特异性免疫组化标志物。3p25.5（即von Hippel-Lindau [VHL]基因位点）的杂合性缺失（LOH）在散发性透明细胞RCC中很常见。作者通过显微切割和聚合酶链反应（PCR）比较原发性和转移性RCC中的LOH，以评估这些技术作为潜在诊断工具的价值。
作者确定了14例已知透明细胞RCC患者，这些患者对疑似转移病灶进行了细针穿刺抽吸（FNA）评估。从原发性肿瘤和相邻正常肾实质的存档组织学玻璃切片进行直视下显微切割。从转移性病灶的存档FNA切片中显微切割恶性细胞簇。细胞学切片先前已用Diff-Quik或巴氏染色法染色。随后进行单步DNA提取和PCR扩增，使用位于VHL基因两侧的多态性标志物D3S1038和D3S1110评估LOH。
14例中的13例在石蜡包埋材料和FNA材料中均含有适合PCR的DNA。13例中的8例对上述标志物为杂合子（信息性），其中6例在原发性和转移性肿瘤中，对于所使用的一种或两种标志物均显示相同的等位基因缺失。其余2例在所使用的两种多态性标志物中未显示VHL基因座处的LOH。
用巴氏染色法或Diff-Quik染色的存档细胞学材料中的DNA对于PCR扩增是可靠的。直视下显微切割结合PCR有可能成为一种有用的技术，用于在细胞学材料中确证性鉴定和诊断转移性透明细胞RCC，因为原发性肿瘤中存在特定的基因异常。随着各种肿瘤中特征性基因异常的确定，当与原发性肿瘤的手术或细胞学材料相比时，使用该技术有可能对FNA材料中的转移性疾病进行确定性评估。这种技术组合的实用性有可能用于形态学上不明确的细胞群体的分子诊断。
