Department of Radiation Oncology, University Hospital, LMU Munich, Munich, Germany.
Department of Nuclear Medicine, University Hospital, LMU Munich, Munich, Germany.
Radiat Oncol. 2017 Nov 10;12(1):176. doi: 10.1186/s13014-017-0902-0.
To determine the potential role of Ga-PSMA positron emission tomography/computed tomography (PET/CT) in radiotherapy (RT) planning for prostate cancer (PCa).
One hundred twenty-nine patients (pts) with Ga-PSMA PET/CT were retrospectively analysed. Potentially influencing factors (androgen deprivation therapy, amount of Ga-PSMA-HBED-CC, PSA doubling time ≤/> 10 months, PSA before PET/CT, T-/N-category and Gleason score) were evaluated by logistic regression analysis. The detection rate of PSMA PET/CT was compared to contrast enhanced CT and its impact on RT management analysed.
One hundred twenty-nine patients (pts) (20 at initial diagnosis, 49 with PSA relapse and 60 with PSA persistence after radical prostatectomy) received PSMA PET/CT prior to RT. The majority of pts. (71.3%) had PET-positive findings (55.1% of pts. with PSA recurrence, 75% of pts. with PSA persistence and 100% of newly diagnosed pts). Median PSA before PET/CT in pts. with pathological findings (n = 92) was 1.90 ng/ml and without (n = 37) 0.30 ng/ml. PSA level at time of PET/CT was the only factor associated with PET-positivity. In pts. with a PSA ≤ 0.2 ng/ml, the detection rate of any lesion was 33.3%, with a PSA of 0.21-0.5 ng/ml 41.2% and with a PSA of 0.51-1.0 ng/ml 69.2%, respectively. Regarding the anatomic distribution of lesions, 42.2% and 14.7% of pts. with relapse or persistence had pelvic lymph node and distant metastases. In pts. at initial diagnosis the detection rate of pelvic lymph nodes and distant metastases was 20% and 10%. Ga-PSMA PET/CT had a high detection rate of PCa recurrence outside the prostatic fossa in pts. being considered for salvage RT (22.4% PET-positive pelvic lymph nodes and 4.1% distant metastases). Compared to CT, PSMA PET/CT had a significantly higher sensitivity in diagnosing rates of local recurrence/primary tumour (10.1% vs. 38%), lymph nodes (15.5% vs. 38.8%) and distant metastases (5.4% vs. 14.0%). This resulted in a modification of RT treatment in 56.6% of pts.
The detection of PCa is strongly associated with PSA level at time of Ga-PSMA PET/CT. PSMA PET/CT differentiates between local, regional and distant metastatic disease with implications for disease management. PSMA PET/CT allows for tumour detection in post-prostatectomy pts. with PSA ≤ 0.5 ng/ml considered for salvage RT.
为了确定 Ga-PSMA 正电子发射断层扫描/计算机断层扫描（PET/CT）在前列腺癌（PCa）放射治疗（RT）计划中的潜在作用。
回顾性分析了 129 名接受 Ga-PSMA PET/CT 检查的患者。通过逻辑回归分析评估了可能影响因素（雄激素剥夺治疗、Ga-PSMA-HBED-CC 量、PSA 倍增时间≤/> 10 个月、PET/CT 前 PSA、T-/N 分期和 Gleason 评分）。比较了 PSMA PET/CT 与对比增强 CT 的检测率，并分析了其对 RT 管理的影响。
129 名患者（pts）（20 名初诊患者，49 名 PSA 复发患者，60 名根治性前列腺切除术后 PSA 持续患者）在 RT 前接受了 PSMA PET/CT 检查。大多数 pts.（71.3%）的 PET 检查结果为阳性（55.1%的 PSA 复发患者，75%的 PSA 持续患者和 100%的初诊患者）。在有病理发现的 pts.（n=92）中，PET/CT 前 PSA 中位数为 1.90ng/ml，无病理发现的 pts.（n=37）中 PSA 中位数为 0.30ng/ml。PET/CT 时的 PSA 水平是唯一与 PET 阳性相关的因素。在 PSA≤0.2ng/ml 的 pts.中，任何病变的检出率为 33.3%，PSA 为 0.21-0.5ng/ml 时为 41.2%，PSA 为 0.51-1.0ng/ml 时为 69.2%。关于病变的解剖分布，42.2%和 14.7%的复发或持续患者有盆腔淋巴结和远处转移。在初诊 pts.中，盆腔淋巴结和远处转移的检出率分别为 20%和 10%。在考虑挽救性 RT 的患者中，Ga-PSMA PET/CT 对前列腺窝外 PCa 复发的检出率较高（22.4%的 PET 阳性盆腔淋巴结和 4.1%的远处转移）。与 CT 相比，PSMA PET/CT 在诊断局部复发/原发性肿瘤（10.1%比 38%）、淋巴结（15.5%比 38.8%）和远处转移（5.4%比 14.0%）的灵敏度方面有显著提高。这导致 56.6%的 pts.改变了 RT 治疗。
PCa 的检出与 Ga-PSMA PET/CT 时的 PSA 水平密切相关。PSMA PET/CT 可区分局部、区域和远处转移性疾病，对疾病管理具有重要意义。PSMA PET/CT 可在 PSA≤0.5ng/ml 的前列腺切除术后 pts.中检测肿瘤，这些 pts.被认为适合进行挽救性 RT。
