Schmidt-Hegemann Nina-Sophie, Stief Christian, Kim Tak-Hyun, Eze Chukwuka, Kirste Simon, Strouthos Iosif, Li Minglun, Schultze-Seemann Wolfgang, Ilhan Harun, Fendler Wolfgang Peter, Bartenstein Peter, Grosu Anca-Ligia, Ganswindt Ute, Belka Claus, Meyer Philipp T, Zamboglou Constantinos
Ludwig-Maximilians-University (LMU), Germany.
Department of Urology, University Hospital, LMU Munich, Germany.
J Nucl Med. 2019 Feb 1;60(2):227-233. doi: 10.2967/jnumed.118.212563. Epub 2018 Jul 12.
Prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT) detects prostate cancer recurrence at low PSA levels. Radiotherapy with dose escalation to the former prostate bed has been associated with improved biochemical recurrence-free survival (BRFS). Thus, we hypothesized that PSMA PET/CT-guided salvage radiotherapy leads to improved BRFS. A total of 204 consecutive patients were referred for salvage radiotherapy following radical prostatectomy. PSMA PET/CT scans were performed and patients with PSA persistence (109 patients) or evidence of distant metastases (5 patients) were excluded from this analysis. Thus, the following analysis is based on a total of 90 patients who underwent PSMA PET/CT prior to radiotherapy due to biochemical recurrence and received salvage radiotherapy. In case of PET-positive findings, antiandrogen therapy was commenced before initiation of radiotherapy. BRFS (PSA ≤ 0.2 ng/ml) was defined as the study endpoint. PET-positive lesions were detected in 42/90 (47%) patients: 24/42 (27%) fossa recurrence only, 12/42 (13%) pelvic lymph nodes only and 6/42 (7%) fossa and pelvic lymph node recurrence. Median PSA before radiotherapy was 0.44 (0.11 - 6.24). Cumulatively, a total dose of 70.0 Gy (67.2 - 72 Gy) was delivered to local macroscopic tumor, 66 Gy (59.4 - 70.2 Gy) to the prostatic fossa, 60.8 Gy (54 - 66 Gy) to PET-positive lymph nodes and 50.4 Gy (45 - 50.4 Gy) to the lymphatic pathways. After a median follow-up of 23 months, BRFS was 78%. Antiandrogen therapy was ongoing in 4 patients at last follow-up. No significant difference in BRFS between PET-positive (74%) vs. PET-negative patients (82%; p>0.05) was observed at last follow-up. Two patients had late genitourinary toxicity grade 3 and no patient had gastrointestinal toxicity ≥ 3 (NCI-CTCAE v4.03). PSMA PET/CT-guided salvage radiotherapy is an effective and safe local treatment option. No difference in BRFS between PET-positive and PET-negative patients was observed, indicating effective targeting of PET-positive lesions. PSMA PET/CT when readily available should be offered to patients with PSA recurrence for treatment individualization.
前列腺特异性膜抗原正电子发射断层扫描/计算机断层扫描（PSMA PET/CT）可在低前列腺特异性抗原（PSA）水平时检测出前列腺癌复发。对原前列腺床进行剂量递增放疗与改善无生化复发生存（BRFS）相关。因此，我们推测PSMA PET/CT引导下的挽救性放疗可改善BRFS。共有204例连续患者在根治性前列腺切除术后接受挽救性放疗。进行了PSMA PET/CT扫描，PSA持续存在的患者（109例）或有远处转移证据的患者（5例）被排除在本分析之外。因此，以下分析基于总共90例因生化复发在放疗前接受PSMA PET/CT检查并接受挽救性放疗的患者。若PET检查结果为阳性，则在放疗开始前开始抗雄激素治疗。将BRFS（PSA≤0.2 ng/ml）定义为研究终点。42/90（47%）例患者检测到PET阳性病灶：仅24/42（27%）例为前列腺床复发，仅12/42（13%）例为盆腔淋巴结复发，6/42（7%）例为前列腺床和盆腔淋巴结复发。放疗前的中位PSA为0.44（0.11 - 6.24）。累计向局部肉眼可见肿瘤给予总剂量70.0 Gy（67.2 - 72 Gy），向前列腺床给予66 Gy（59.4 - 70.2 Gy），向PET阳性淋巴结给予60.8 Gy（54 - 66 Gy），向淋巴途径给予50.4 Gy（45 - 50.4 Gy）。中位随访23个月后，BRFS为78%。在最后一次随访时，4例患者仍在进行抗雄激素治疗。在最后一次一次随访时，未观察到PET阳性患者（74%）与PET阴性患者（82%；p＞＞0.05）之间的BRFS有显著差异。2例患者出现3级晚期泌尿生殖系统毒性，无患者出现≥3级胃肠道毒性（美国国立癌症研究所不良事件通用术语标准第4.03版）。PSMA PET/CT引导下的挽救性放疗是一种有效且安全的局部治疗选择。未观察到PET阳性和PET阴性患者之间BRFS有差异，表明对PET阳性病灶的靶向治疗有效。对于PSA复发的患者，若能方便地进行PSMA PET/CT检查，应提供该检查以实现个体化治疗。
