Uprimny Christian, Kroiss Alexander Stephan, Decristoforo Clemens, Fritz Josef, von Guggenberg Elisabeth, Kendler Dorota, Scarpa Lorenza, di Santo Gianpaolo, Roig Llanos Geraldo, Maffey-Steffan Johanna, Horninger Wolfgang, Virgolini Irene Johanna
Department of Nuclear Medicine, Medical University Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria.
Department of Medical Statistics, Informatics and Health Economics, Medical University Innsbruck, Innsbruck, Austria.
Eur J Nucl Med Mol Imaging. 2017 Jun;44(6):941-949. doi: 10.1007/s00259-017-3631-6. Epub 2017 Jan 31.
Prostate cancer (PC) cells typically show increased expression of prostate-specific membrane antigen (PSMA), which can be visualized by Ga-PSMA-11 PET/CT. The aim of this study was to assess the intensity of Ga-PSMA-11 uptake in the primary tumour and metastases in patients with biopsy-proven PC prior to therapy, and to determine whether a correlation exists between the primary tumour-related Ga-PSMA-11 accumulation and the Gleason score (GS) or prostate-specific antigen (PSA) level.
Ninety patients with transrectal ultrasound biopsy-proven PC (GS 6-10; median PSA: 9.7 ng/ml) referred for Ga-PSMA-11 PET/CT were retrospectively analysed. PET images were analysed visually and semiquantitatively by measuring the maximum standardized uptake value (SUV). The SUV of the primary tumour and pathologic lesions suspicious for lymphatic or distant metastases were then compared to the physiologic background activity of normal prostate tissue and gluteal muscle. The SUV of the primary tumour was assessed in relation to both PSA level and GS.
Eighty-two patients (91.1%) demonstrated pathologic tracer accumulation in the primary tumour that exceeded physiologic tracer uptake in normal prostate tissue (median SUV: 12.5 vs. 3.9). Tumours with GS of 6, 7a (3+4) and 7b (4+3) showed significantly lower Ga-PSMA-11 uptake, with median SUV of 5.9, 8.3 and 8.2, respectively, compared to patients with GS >7 (median SUV: 21.2; p < 0.001). PC patients with PSA ≥10.0 ng/ml exhibited significantly higher uptake than those with PSA levels <10.0 ng/ml (median SUV: 17.6 versus 7.7; p < 0.001). In 24 patients (26.7%), 82 lymph nodes with pathologic tracer accumulation consistent with metastases were detected (median SUV: 10.6). Eleven patients (12.2%) revealed 55 pathologic osseous lesions suspicious for bone metastases (median SUV: 11.6).
The GS and PSA level correlated with the intensity of tracer accumulation in the primary tumours of PC patients on Ga-PSMA-11 PET/CT. As PC tumours with GS 6+7 and patients with PSA values ≤10 ng/ml showed significantly lower Ga-PSMA-11 uptake, Ga-PSMA-11 PET/CT should be preferentially applied for primary staging of PC in patients with GS >7 or PSA levels ≥10 ng/ml.
前列腺癌细胞通常显示前列腺特异性膜抗原（PSMA）表达增加，可通过镓-PSMA-11 PET/CT进行可视化。本研究的目的是评估经活检证实的前列腺癌患者在治疗前原发肿瘤和转移灶中镓-PSMA-11摄取的强度，并确定原发肿瘤相关的镓-PSMA-11积聚与 Gleason 评分（GS）或前列腺特异性抗原（PSA）水平之间是否存在相关性。
回顾性分析90例经直肠超声活检证实为前列腺癌（GS 6 - 10；中位 PSA：9.7 ng/ml）并接受镓-PSMA-11 PET/CT检查的患者。通过测量最大标准化摄取值（SUV）对PET图像进行视觉和半定量分析。然后将原发肿瘤以及可疑为淋巴或远处转移的病理病变的SUV与正常前列腺组织和臀大肌的生理本底活性进行比较。根据PSA水平和GS评估原发肿瘤的SUV。
82例患者（91.1%）在原发肿瘤中显示出病理性示踪剂积聚，超过了正常前列腺组织中的生理性示踪剂摄取（中位SUV：12.5对3.9）。GS为6、7a（3 + 4）和7b（4 + 3）的肿瘤显示镓-PSMA-11摄取显著较低，中位SUV分别为5.9、8.3和8.2，而GS>7的患者中位SUV为21.2（p < 0.001）。PSA≥10.0 ng/ml的前列腺癌患者的摄取显著高于PSA水平<10.0 ng/ml的患者（中位SUV：17.6对7.7；p < 0.001）。在24例患者（26.7%）中，检测到82个淋巴结有与转移一致的病理性示踪剂积聚（中位SUV：10.6）。11例患者（12.2%）发现55个可疑为骨转移的病理性骨病变（中位SUV：11.6）。
在镓-PSMA-11 PET/CT上，GS和PSA水平与前列腺癌患者原发肿瘤中示踪剂积聚的强度相关。由于GS为6 + 7的前列腺癌肿瘤和PSA值≤10 ng/ml的患者显示镓-PSMA-11摄取显著较低，镓-PSMA-11 PET/CT应优先应用于GS>7或PSA水平≥10 ng/ml患者的前列腺癌原发分期。
