Pittman K, Burchill S, Smith B, Southgate J, Joffe J, Gore M, Selby P
ICRF Cancer Medicine Research Unit, St. James's University Hospital, Leeds, UK.
Ann Oncol. 1996 Mar;7(3):297-301. doi: 10.1093/oxfordjournals.annonc.a010575.
Circulating tumour cells in the peripheral blood may be important for haematogenous spread of disease. The detection of these cells may therefore be a poor prognostic indicator. Reverse-transcriptase polymerase chain reaction (RT-PCR) of target tumour-specific protein expression has been used as a sensitive and specific method for the detection of these tumour cells. Initial reports by our laboratory and other suggested RT-PCR amplification of the enzyme tyrosinase is a useful method for detection of melanoma cells in peripheral blood [1-3].
In this report, we have evaluated the application of RT-PCR for tyrosinase mRNA as a detection method for melanoma cells in a series of 24 patients with advanced, metastatic malignant melanoma. A single round RT-PCR method is described.
The single round RT-PCR was as sensitive as previously described nested PCR methods, and had the advantage of reduced contamination risks. Blood samples from three out of the twenty-four patients were positive.
The frequency of tumour cell detection in peripheral blood from patients with advanced disease was lower than previously reported. It may be only small numbers of circulating tumour cells are present at any one time in the peripheral blood of patients with malignant melanoma. If this is the case increased sampling will improve detection frequency. Alternatively, dissemination of melanoma through peripheral blood may be a rare event. In our experience, RT-PCR for tyrosinase mRNA as a staging test for melanoma patients must be interpreted cautiously.
外周血中的循环肿瘤细胞对于疾病的血行播散可能很重要。因此，检测这些细胞可能是一个不良的预后指标。针对肿瘤特异性蛋白表达的逆转录聚合酶链反应（RT-PCR）已被用作检测这些肿瘤细胞的灵敏且特异的方法。我们实验室及其他机构的初步报告表明，RT-PCR扩增酪氨酸酶是检测外周血中黑色素瘤细胞的一种有用方法[1-3]。
在本报告中，我们评估了RT-PCR检测酪氨酸酶mRNA作为检测方法在24例晚期转移性恶性黑色素瘤患者中的应用。描述了一种单轮RT-PCR方法。
单轮RT-PCR与先前描述的巢式PCR方法一样灵敏，且具有降低污染风险的优点。24例患者中有3例的血样呈阳性。
晚期疾病患者外周血中肿瘤细胞的检测频率低于先前报道。可能在恶性黑色素瘤患者的外周血中，任何时候仅存在少量循环肿瘤细胞。如果是这种情况，增加采样将提高检测频率。或者，黑色素瘤通过外周血的播散可能是一种罕见事件。根据我们的经验，RT-PCR检测酪氨酸酶mRNA作为黑色素瘤患者的分期检查必须谨慎解读。
