The James Buchanan Brady Urological Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Urology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
The James Buchanan Brady Urological Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Urology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
J Urol. 2018 Jun;199(6):1494-1501. doi: 10.1016/j.juro.2018.01.033. Epub 2018 Jan 12.
Prostate circulating tumor cells escape into peripheral blood and enter bone marrow as disseminated tumor cells, representing an early step before conventionally detectable metastasis. It is unclear how frequently this occurs in localized disease and existing detection methods rely on epithelial markers with low specificity and sensitivity. We used multiple methodologies of disseminated tumor cell detection in bone marrow harvested at radical prostatectomy.
Bone marrow was harvested from 208 clinically localized cases, 16 controls and 5 metastatic cases with peripheral blood obtained from 37 metastatic cases. Samples were evaluated at 4 centers with 4 distinct platforms using antibody enrichment with the AdnaTest (Qiagen®) or VERSA (versatile exclusion based rare sample analysis), or whole sample interrogation with the RareCyte platform (Seattle, Washington) or HD-SCA (high definition single cell assay) using traditional epithelial markers and prostate specific markers. We investigated the sensitivity and specificity of these markers by evaluating expression levels in control and metastatic cases.
EpCAM, NKX3.1 and AR were nonspecifically expressed in controls and in most samples using AdnaTest with no relation to perioperative variables. Only 1 patient with localized disease showed positive results for the prostate specific marker PSA. With the VERSA platform no localized case demonstrated disseminated tumor cells. With the RareCyte and HD-SCA platforms only a single patient had 1 disseminated tumor cell.
Evaluation across multiple platforms revealed that epithelial markers are nonspecific in bone marrow and, thus, not suitable for disseminated tumor cell detection. Using prostate specific markers disseminated tumor cells were typically not detected in patients with localized prostate cancer.
前列腺循环肿瘤细胞从外周血中逃逸并进入骨髓，成为播散性肿瘤细胞，这代表了在常规检测到转移之前的早期步骤。目前尚不清楚这种情况在局部疾病中发生的频率，并且现有的检测方法依赖于上皮标记物，其特异性和敏感性都较低。我们使用了几种在根治性前列腺切除术中采集的骨髓中播散性肿瘤细胞检测方法。
从 208 例临床局限性病例、16 例对照病例和 5 例转移性病例的骨髓中采集样本，从 37 例转移性病例的外周血中采集样本。这些样本在 4 个中心使用 4 种不同的平台进行了评估，使用 AdnaTest（Qiagen®）或 VERSA（多功能排除的稀有样本分析）的抗体富集，或使用 RareCyte 平台（华盛顿州西雅图）或 HD-SCA（高清晰度单细胞分析）的全样本检测，使用传统的上皮标记物和前列腺特异性标记物。我们通过评估对照病例和转移性病例中的表达水平，研究了这些标记物的敏感性和特异性。
EpCAM、NKX3.1 和 AR 在对照病例和使用 AdnaTest 时均无特异性表达，与围手术期变量无关。只有 1 例局限性疾病患者的前列腺特异性标记物 PSA 检测结果为阳性。使用 VERSA 平台，没有局限性病例显示播散性肿瘤细胞。使用 RareCyte 和 HD-SCA 平台，只有 1 例患者有 1 个播散性肿瘤细胞。
通过对多个平台进行评估，发现上皮标记物在骨髓中无特异性，因此不适合用于播散性肿瘤细胞检测。使用前列腺特异性标记物，通常无法在局限性前列腺癌患者中检测到播散性肿瘤细胞。
