Schiller Kilian, Sauter K, Dewes S, Eiber M, Maurer T, Gschwend J, Combs S E, Habl G
Department of Radiation Oncology, Technical University of Munich (TUM), Ismaninger Strasse 22, 81675, Munich, Germany.
Department of Nuclear Medicine, Technical University Munich (TUM), Munich, Germany.
Eur J Nucl Med Mol Imaging. 2017 Sep;44(10):1656-1662. doi: 10.1007/s00259-017-3746-9. Epub 2017 Jun 23.
Salvage radiotherapy (SRT) after radical prostatectomy (RPE) and lymphadenectomy (LAE) is the appropriate radiotherapy option for patients with persistent/ recurrent prostate cancer (PC). Ga-PSMA-PET imaging has been shown to accurately detect PC lesions in a primary setting as well as for local recurrence or for lymph node (LN) metastases.
In this study we evaluated the patterns of recurrence after RPE in patients with PC, putting a highlight on the differentiation between sites that would have been covered by a standard radiation therapy (RT) field in consensus after the RTOG consensus and others that would have not.
Thirty-one out of 83 patients (37%) with high-risk PC were the subject of our study. Information from Ga-PSMA-PET imaging was used to individualize treatment plans to include suspicious lesions as well as possibly boost sites with tracer uptake in LN or the prostate bed. For evaluation, Ga-PSMA-PET-positive LN were contoured in a patient dataset with a standard lymph drainage (RTOG consensus on CTV definition of pelvic lymph nodes) radiation field depicting color-coded nodes that would have been infield or outfield of that standard lymph drainage field and thereby visualizing typical patterns of failure of a "blind" radiation therapy after RPE and LAE.
Compared to negative conventional imaging (CT/MRI), lesions suspicious for PC were detected in 27/31 cases (87.1%) by Ga-PSMA-PET imaging, which resulted in changes to the radiation concept. There were 16/31 patients (51.6%) that received a simultaneous integrated boost (SIB) to a subarea of the prostate bed (in only three cases this dose escalation would have been planned without the additional knowledge of Ga-PSMA-PET imaging) and 18/31 (58.1%) to uncommon (namely presacral, paravesical, pararectal, preacetabular and obturatoric) LN sites. Furthermore, 14 patients (45.2%) had a changed TNM staging result by means of Ga-PSMA-PET imaging.
Compared to conventional CT or MRI staging, Ga-PSMA-PET imaging detects more PC lesions and, thus, significantly influences radiation planning in recurrent prostate cancer patients enabling individually tailored treatment.
根治性前列腺切除术（RPE）和淋巴结清扫术（LAE）后的挽救性放疗（SRT）是持续性/复发性前列腺癌（PC）患者合适的放疗选择。已证明镓-PSMA-PET成像能准确检测原发性PC病变以及局部复发或淋巴结（LN）转移情况。
在本研究中，我们评估了PC患者RPE后的复发模式，重点区分RTOG共识后标准放疗（RT）野覆盖的部位与未覆盖的部位。
83例高危PC患者中的31例（37%）纳入我们的研究。来自镓-PSMA-PET成像的信息用于个体化治疗计划，以纳入可疑病变以及LN或前列腺床有示踪剂摄取的可能需加量照射的部位。为进行评估，在一个具有标准淋巴引流（RTOG关于盆腔淋巴结CTV定义的共识）放疗野的患者数据集中勾勒出镓-PSMA-PET阳性LN，该放疗野描绘了按颜色编码的淋巴结，这些淋巴结在该标准淋巴引流野内或外，从而可视化RPE和LAE后“盲目”放疗的典型失败模式。
与传统成像阴性（CT/MRI）相比，镓-PSMA-PET成像在27/31例（87.1%）中检测到可疑PC病变，这导致放疗方案改变。16/31例患者（51.6%）接受了对前列腺床一个亚区域的同步整合加量（SIB）（仅3例在没有镓-PSMA-PET成像额外信息的情况下就已计划进行这种剂量递增），18/31例（58.1%）接受了对不常见（即骶前、膀胱旁、直肠旁、髋臼前和闭孔）LN部位的加量照射。此外，14例患者（45.2%）通过镓-PSMA-PET成像改变了TNM分期结果。
与传统CT或MRI分期相比，镓-PSMA-PET成像能检测到更多PC病变，因此显著影响复发性前列腺癌患者的放疗计划，实现个体化定制治疗。
