Department of Radiation Oncology, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois.
Department of Radiology, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois.
Pract Radiat Oncol. 2020 Sep-Oct;10(5):354-362. doi: 10.1016/j.prro.2020.05.007. Epub 2020 May 25.
Conventional imaging rarely localizes the site(s) of prostate cancer recurrence in patients undergoing evaluation for salvage radiation therapy (sRT) after radical prostatectomy (RP). LOCATE (NCT02680041) was a prospective, multicenter study investigating the impact of F-fluciclovine positron emission tomography and computed tomography (PET/CT) on the management of patients with biochemical recurrence of prostate cancer after curative-intent radiation or RP and negative or equivocal conventional imaging. Our objective was to determine the impact of F-fluciclovine PET/CT on treatment decisions for men planning to undergo sRT for biochemical recurrence post-RP.
We conducted a subgroup analysis of post-RP patients enrolled in LOCATE who were planning to undergo sRT with or without hormonal therapy based on prescan documentation. F-Fluciclovine PET/CT was performed according to standardized procedures. The treatment plan postscan was compared with the prescan plan, and Fisher exact test was used to determine the impact of prescan prostate-specific antigen (PSA) and Gleason sum (GS) on positivity and anatomic patterns of uptake.
A total of 114 patients (median prescan PSA 0.42 [interquartile range, 0.3-1.1] ng/mL) met selection criteria (54% of patients in LOCATE). Forty-eight (42%) had F-fluciclovine-avid lesions. Twelve patients (11%) had positive findings only in the prostate bed, 24 (21%) had positivity only in the pelvis (prostate bed or pelvic nodes), and 24 (21%) had extrapelvic findings. PSA >0.5 ng/mL and GS ≥8 were associated with a higher risk of extrapelvic positivity (P < .05). Postscan, 55 (48%) patients had a management change; 37 (32%) had a change in overall treatment approach (ie, omission of sRT); and 18 (16%) had sRT target modification.
F-Fluciclovine PET/CT is positive in nearly half of patients planning to undergo post-RP sRT with negative/equivocal conventional imaging, with findings frequently leading to changes in management. PSA >0.5 ng/mL and GS ≥8 are associated with a higher risk of extrapelvic positive findings.
根治性前列腺切除术（RP）后接受挽救性放疗（sRT）评估的患者，常规影像学很少能定位前列腺癌复发的部位。LOCATE（NCT02680041）是一项前瞻性、多中心研究，旨在调查氟[18F] 氟代脱氧葡萄糖正电子发射断层扫描和计算机断层扫描（PET/CT）对接受根治性放疗或 RP 后生化复发且常规影像学阴性或不确定的前列腺癌患者的管理影响。我们的目的是确定氟[18F] 氟代脱氧葡萄糖 PET/CT 对计划接受 RP 后生化复发行 sRT 的男性治疗决策的影响。
我们对 LOCATE 中入组的 RP 后患者进行了亚组分析，这些患者根据扫描前的记录计划行 sRT 治疗，包括或不包括激素治疗。氟[18F] 氟代脱氧葡萄糖 PET/CT 按标准程序进行。扫描后治疗计划与扫描前计划进行比较，采用 Fisher 确切检验确定扫描前前列腺特异性抗原（PSA）和 Gleason 评分（GS）对阳性和摄取的解剖模式的影响。
共有 114 名患者（中位扫描前 PSA 0.42[四分位距，0.3-1.1]ng/mL）符合入选标准（LOCATE 患者的 54%）。48 名（42%）患者有氟[18F] 氟代脱氧葡萄糖摄取病灶。12 名（11%）患者仅在前列腺床发现阳性病灶，24 名（21%）患者仅在骨盆（前列腺床或骨盆淋巴结）发现阳性病灶，24 名（21%）患者发现盆腔外病灶。PSA＞0.5ng/mL 和 GS≥8 与盆腔外阳性发现的风险较高相关（P＜0.05）。扫描后，55 名（48%）患者的管理发生变化；37 名（32%）患者的整体治疗方法发生变化（即，省略 sRT）；18 名（16%）患者的 sRT 靶区发生变化。
在接受阴性/不确定的常规影像学检查的计划接受 RP 后 sRT 的患者中，氟[18F] 氟代脱氧葡萄糖 PET/CT 有近一半的患者呈阳性，且结果常导致治疗管理的改变。PSA＞0.5ng/mL 和 GS≥8 与盆腔外阳性发现的风险较高相关。
