Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.
Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands.
J Nucl Med. 2020 Nov;61(11):1607-1614. doi: 10.2967/jnumed.119.241109. Epub 2020 Mar 13.
For individual treatment decisions in patients with metastatic prostate cancer (mPC), molecular diagnostics are increasingly used. Bone metastases are frequently the only source for obtaining metastatic tumor tissue. However, the success rate of CT-guided bone biopsies for molecular analyses in mPC patients is approximately only 40%. PET using Ga prostate-specific membrane antigen (Ga-PSMA) is a promising tool to improve the harvest rate of bone biopsies for molecular analyses. The aim of this study was to determine the success rate of Ga-PSMA-guided bone biopsies for molecular diagnostics in mPC patients. Within a prospective multicenter whole-genome sequencing trial (NCT01855477), 69 mPC patients underwent Ga-PSMA PET/CT before bone biopsy. The primary endpoint was the success rate (tumor percentage ≥ 30%) of Ga-PSMA-guided bone biopsies. At biopsy sites, Ga-PSMA uptake was quantified using rigid-body image registration of Ga-PSMA PET/CT and interventional CT. Actionable somatic alterations were identified. The success rate of Ga-PSMA-guided biopsies for molecular analyses was 70%. At biopsy sites categorized as positive, inconclusive, or negative for Ga-PSMA uptake, 70%, 64%, and 36% of biopsies were tumor-positive (≥30%), respectively ( = 0.0610). In tumor-positive biopsies, Ga-PSMA uptake was significantly higher ( = 0.008), whereas radiodensity was significantly lower ( = 0.006). With an area under the curve of 0.84 and 0.70, both Ga-PSMA uptake (SUV) and radiodensity (mean Hounsfield units) were strong predictors for a positive biopsy. Actionable somatic alterations were detected in 73% of the sequenced biopsies. In patients with mPC, Ga-PSMA PET/CT improves the success rate of CT-guided bone biopsies for molecular analyses, thereby identifying actionable somatic alterations in more patients. Therefore, Ga-PSMA PET/CT may be considered for guidance of bone biopsies in both clinical practice and clinical trials.
对于转移性前列腺癌（mPC）患者的个体化治疗决策，越来越多地使用分子诊断。骨转移通常是获得转移性肿瘤组织的唯一来源。然而，在 mPC 患者中，CT 引导的骨活检进行分子分析的成功率约为 40%。使用 Ga 前列腺特异性膜抗原（Ga-PSMA）的 PET 是提高骨活检分子分析采集率的有前途的工具。本研究的目的是确定 Ga-PSMA 引导的 mPC 患者骨活检进行分子诊断的成功率。
在一项前瞻性多中心全基因组测序试验（NCT01855477）中，69 名 mPC 患者在骨活检前接受了 Ga-PSMA PET/CT。主要终点是 Ga-PSMA 引导的骨活检的成功率（肿瘤百分比≥30%）。在活检部位，使用 Ga-PSMA PET/CT 和介入 CT 的刚体图像配准来量化 Ga-PSMA 摄取。确定了可操作的体细胞改变。
用于分子分析的 Ga-PSMA 引导活检的成功率为 70%。在 Ga-PSMA 摄取分类为阳性、不确定或阴性的活检部位，分别有 70%、64%和 36%的活检为肿瘤阳性（≥30%）（=0.0610）。在肿瘤阳性的活检中，Ga-PSMA 摄取明显更高（=0.008），而放射性密度明显更低（=0.006）。曲线下面积分别为 0.84 和 0.70，Ga-PSMA 摄取（SUV）和放射性密度（平均亨斯菲尔德单位）都是阳性活检的有力预测因子。在测序的活检中，73%检测到可操作的体细胞改变。
在 mPC 患者中，Ga-PSMA PET/CT 提高了 CT 引导的骨活检进行分子分析的成功率，从而使更多患者能够识别出可操作的体细胞改变。因此，Ga-PSMA PET/CT 可考虑用于指导临床实践和临床试验中的骨活检。
