68Ga-PSMA-PET screening and transponder-guided salvage radiotherapy to the prostate bed alone for biochemical recurrence following prostatectomy: interim outcomes of a phase II trial

Bowden, P; See, AW; So, K; Lawrentschuk, N; Moon, D; Murphy, DG; Rao, R; Crosthwaite, A; King, D; Haxhimolla, H; Grummet, J; Ruljancich, P; Gyomber, D; Landau, A; Campbell, N; Frydenberg, M; Smyth, LML; Nolan, S; Gwini, SM; McKenzie, DP

Author(s): Bowden, P; See, AW; So, K; Lawrentschuk, N; Moon, D; Murphy, DG; Rao, R; Crosthwaite, A; King, D; Haxhimolla, H; Grummet, J; Ruljancich, P; Gyomber, D; Landau, A; Campbell, N; Frydenberg, M; Smyth, LML; Nolan, S; Gwini, SM; McKenzie, DP;
Details: Publication Year 2021,Volume 39,Issue #11,Page 4117-4125
Journal Title: World Journal of Urology
Publication Type: Research article
Abstract: PURPOSE: To evaluate outcomes for men with biochemically recurrent prostate cancer who were selected for transponder-guided salvage radiotherapy (SRT) to the prostate bed alone by (68)Ga-labelled prostate-specific membrane antigen positron emission tomography ((68)Ga-PSMA-PET). METHODS: This is a single-arm, prospective study of men with a prostate-specific antigen (PSA) level rising to 0.1-2.5 ng/mL following radical prostatectomy. Patients were staged with (68)Ga-PSMA-PET and those with a negative finding, or a positive finding localised to the prostate bed, continued to SRT only to the prostate bed alone with real-time target-tracking using electromagnetic transponders. The primary endpoint was freedom from biochemical relapse (FFBR, PSA > 0.2 ng/mL from the post-radiotherapy nadir). Secondary endpoints were time to biochemical relapse, toxicity and patient-reported quality of life (QoL). RESULTS: Ninety-two patients (median PSA of 0.18 ng/ml, IQR 0.12-0.36), were screened with (68)Ga-PSMA-PET and metastatic disease was found in 20 (21.7%) patients. Sixty-nine of 72 non-metastatic patients elected to proceed with SRT. At the interim (3-year) analysis, 32 (46.4%) patients (95% CI 34.3-58.8%) were FFBR. The median time to biochemical relapse was 16.1 months. The rate of FFBR was 82.4% for ISUP grade-group 2 patients. Rates of grade 2 or higher gastrointestinal and genitourinary toxicity were 0% and 15.2%, respectively. General health and disease-specific QoL remained stable. CONCLUSION: Pre-SRT (68)Ga-PSMA-PET scans detect metastatic disease in a proportion of patients at low PSA levels but fail to improve FFBR. Transponder-guided SRT to the prostate bed alone is associated with a favourable toxicity profile and preserved QoL. TRIAL REGISTRATION NUMBER: ACTRN12615001183572, 03/11/2015, retrospectively registered.
Keywords: Aged; *Gallium Isotopes; *Gallium Radioisotopes; Humans; Male; Middle Aged; Neoplasm Recurrence, Local/blood/*radiotherapy; Positron-Emission Tomography/*methods; Prospective Studies; Prostate-Specific Antigen/blood; Prostatectomy; Prostatic Neoplasms/*radiotherapy/surgery; *Radiopharmaceuticals; Salvage Therapy/*methods; Treatment Outcome
Department(s): Surgical Oncology
PubMed ID: 34076753
Publisher's Version: https://doi.org/10.1007/s00345-021-03735-0
Open Access at Publisher's Site: https://doi.org/10.1007/s00345-021-03735-0
Terms of Use/Rights Notice: Refer to copyright notice on published article.

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Last Modified: 2025-06-13 07:51:46