Division of Radiation Oncology, Department of Oncology, London Health Sciences Centre and Western University, London, Canada.
Department of Radiology, Hamilton Health Sciences Centre and McMaster University, Hamilton, Canada.
Int J Radiat Oncol Biol Phys. 2020 Mar 1;106(3):546-555. doi: 10.1016/j.ijrobp.2019.11.001. Epub 2019 Nov 12.
Radio-recurrent prostate cancer is typically detected by a rising prostate-specific antigen and may reflect local or distant disease. Positron emission tomography (PET) radiotracers targeting prostate-specific membrane antigen, such as 18F-DCFPyL have shown promise in restaging men with recurrent disease postprostatectomy but are less well characterized in the setting of radio-recurrent disease.
A prospective, multi-institutional study was conducted to evaluate the effect of 18F-DCFPyL PET/computed tomography (CT) when added to diagnostic imaging (DI; CT abdomen and pelvis, bone scan, multiparametric magnetic resonance imaging pelvis) for men with radio-recurrent prostate cancer. All men were imaged with DI and subsequently underwent 18F-DCFPyL PET/CT with local and central reads. Tie break reads were performed as required. Management questionnaires were completed after DI and again after 18F-DCFPyL PET/CT. Discordance in patterns of disease detected with 18F-DCFPyL PET/CT versus DI and changes in management were characterized.
Seventy-nine men completed the study. Most men had T1 disease (62%) and Gleason score <7 (95%). Median prostate-specific antigen at diagnosis was 7.4 ng/mL and at relapse was 4.8 ng/mL. DI detected isolated intraprostatic recurrence in 38 out of 79 men (48%), regional nodal recurrence in 9 out of 79 (11%), distant disease in 12 out of 79 (15%), and no disease in 26 out of 79 (33%). 18F-DCFPyL PET/CT detected isolated intraprostatic recurrence in 38 out of 79 men (48%), regional nodal recurrence in 21 out of 79 (27%), distant disease in 24 out of 79 (30%), and no disease in 10 out of 79 (13%). DI identified 8 out of 79 (10%) patients to have oligometastatic disease, compared with 21 out of 79 (27%) with 18F-DCFPyL PET/CT. 18F-DCFPyL PET/CT changed proposed management in 34 out of 79 (43%) patients.
18F-DCFPyL PET/CT identified extraprostatic disease in twice as many men with radio-recurrent prostate cancer compared with DI and detected a site of recurrence in 87% of men compared with 67% with DI. Furthermore, 18F-DCFPyL PET/CT identified potentially actionable disease (prostate only recurrence or oligometastatic disease) in 75% of men and changed proposed management in 43% of men.
放射性复发的前列腺癌通常通过前列腺特异性抗原的升高来检测，可能反映局部或远处疾病。针对前列腺特异性膜抗原的正电子发射断层扫描（PET）放射性示踪剂，如 18F-DCFPyL，在前列腺切除术后复发的男性中进行疾病再分期方面显示出了一定的前景，但在放射性复发疾病的情况下，其特征描述较少。
进行了一项前瞻性、多机构研究，以评估 18F-DCFPyL PET/CT 在诊断影像学（腹部和骨盆 CT、骨扫描、多参数磁共振成像骨盆）的基础上，对放射性复发前列腺癌患者的作用。所有患者均进行了 DI 检查，随后进行了 18F-DCFPyL PET/CT 检查，包括局部和中央读取。需要时进行 Tie break 读取。在 DI 检查后和 18F-DCFPyL PET/CT 检查后，分别完成管理问卷调查。描述了 18F-DCFPyL PET/CT 与 DI 检测到的疾病模式的差异以及管理的变化。
79 名男性完成了研究。大多数男性为 T1 期疾病（62%）和 Gleason 评分<7（95%）。诊断时的前列腺特异性抗原中位数为 7.4ng/mL，复发时为 4.8ng/mL。DI 检测到 79 名男性中有 38 名（48%）孤立性前列腺内复发、9 名（11%）区域性淋巴结复发、12 名（15%）远处疾病和 26 名（33%）无疾病。18F-DCFPyL PET/CT 在 79 名男性中有 38 名（48%）检测到孤立性前列腺内复发、21 名（27%）区域性淋巴结复发、24 名（30%）远处疾病和 10 名（13%）无疾病。DI 发现 8 名（10%）患者存在寡转移疾病，而 18F-DCFPyL PET/CT 发现 21 名（27%）患者存在寡转移疾病。18F-DCFPyL PET/CT 改变了 79 名男性中的 34 名（43%）患者的拟议治疗方案。
与 DI 相比，18F-DCFPyL PET/CT 在放射性复发前列腺癌患者中发现了两倍的前列腺外疾病，并在 87%的男性中检测到复发部位，而在 67%的男性中通过 DI 检测到。此外，18F-DCFPyL PET/CT 在 75%的男性中发现了潜在的可治疗性疾病（仅前列腺复发或寡转移疾病），并改变了 43%的男性的拟议治疗方案。
