PSMA PET/CT to evaluate response to SBRT for prostate cancer bone metastases
Abstract
Background: In the current study we evaluated 68Ga PSMA PET/ CT to measure local control of bone metastasis in oligometastatic prostate cancer patients treated with SBRT.
Materials and methods: After the institutional review board approval, a retrospective review of medical records of consecutive prostate cancer patients treated between 2014 and 2018 was conducted. Only medical records of patients that were treated with SBRT for bone metastasis and had pre-and post-SBRT 68Ga PSMA PET/CT scans were included in our study. Data extracted from the medical files included patient-related (age), disease-related (Gleason score, site of metastasis), and treatment-related factors and outcomes.
Results: During the study period, a total of 12 patients (15 lesions) were included, with a median age of 73 years. The median follow-up was 26.5 months (range 13–45 months). Median time of 68Ga PSMA PET/ CT follow up was 17.0 months (range 3–39 months).
The median pre-treatment PSA was 2 ng/mL (range 0.56–44 ng/mL) vs. post treatment PSA nadir of 0.01 ng/mL (0.01–4.32) with a median time to nadir of 7 months (range, 2–12). Local control was 93% during the follow up period and there was correlation with PSMA avidity on PET. None patients developed recurrences in the treated bone. None of the patients had grade 3 or more toxicities during follow-up.
Conclusions: SBRT is a highly effective and safe method for treatment of prostate cancer bone metastases. More studies are required to determine if SBRT provides greater clinical benefit than standard fractionation for oligometastatic prostate cancer patients. 68Ga PSMA PET/CT should be further investigated for delineation and follow-up.
Keywords: PSMAPETprostateradiationstereotacticSBRTcancer
References
- Slaoui A, Albisinni S, Aoun F, et al. A systematic review of contemporary management of oligometastatic prostate cancer: fighting a challenge or tilting at windmills? World J Urol. 2019; 37(11): 2343–2353.
- Kamran SC, D'Amico AV. Radiation Therapy for Prostate Cancer. Hematol Oncol Clin North Am. 2020; 34(1): 45–69.
- Palma DA, Olson R, Harrow S, et al. Stereotactic ablative radiotherapy for the comprehensive treatment of 4-10 oligometastatic tumors (SABR-COMET-10): study protocol for a randomized phase III trial. BMC Cancer. 2019; 19(1): 816.
- Plouznikoff N, Artigas C, Sideris S, et al. Early Detection of Metastatic Prostate Cancer Relapse on 68Ga-PSMA-11 PET/CT in a Patient Still Exhibiting Biochemical Response. Clin Nucl Med. 2020; 45(1): 81–82.
- Cox BW, Spratt DE, Lovelock M, et al. International Spine Radiosurgery Consortium consensus guidelines for target volume definition in spinal stereotactic radiosurgery. Int J Radiat Oncol Biol Phys. 2012; 83(5): e597–e605.
- Kim EY, Chapman TR, Ryu S, et al. ACR Appropriateness Criteria(®) non-spine bone metastases. J Palliat Med. 2015; 18(1): 11–17.
- Bedard G, McDonald R, Poon I, et al. Stereotactic body radiation therapy for non-spine bone metastases--a review of the literature. Ann Palliat Med. 2016; 5(1): 58–66.
- Lo SS, Tseng Y, Halasz LM, Kim EY. Sine Tumors and Non-Sine Bone Metastases. In: Kaidar-Person O, Chen R. ed. Hyofractionated and Stereotactic Radiation Theray: A Practical Guide. Springer International Publishing, Cham 2018: 341–364.
- Lee JA. Segmentation of positron emission tomography images: some recommendations for target delineation in radiation oncology. Radiother Oncol. 2010; 96(3): 302–307.
- Siva S, Bressel M, Murphy DG, et al. Stereotactic Abative Body Radiotherapy (SABR) for Oligometastatic Prostate Cancer: A Prospective Clinical Trial. Eur Urol. 2018; 74(4): 455–462.
- Tong D, Gillick L, Hendrickson F. The palliation of symptomatic osseous metastases final results of the study by the radiation therapy oncology group. Cancer. 1982; 50(5): 893–899, doi: 10.1002/1097-0142(19820901)50:5<893::aid-cncr2820500515>3.0.co;2-y.
- Gupta M, Choudhury PS, Rawal S, et al. Evaluation of RECIST, PERCIST, EORTC, and MDA Criteria for Assessing Treatment Response with Ga68-PSMA PET-CT in Metastatic Prostate Cancer Patient with Biochemical Progression: a Comparative Study. Nucl Med Mol Imaging. 2018; 52(6): 420–429.
- Wahl RL, Jacene H, Kasamon Y, et al. From RECIST to PERCIST: Evolving Considerations for PET response criteria in solid tumors. J Nucl Med. 2009; 50 Suppl 1: 122S–50S.
- Ito K, Shimizuguchi T, Nihei K, et al. Patterns of Intraosseous Recurrence After Stereotactic Body Radiation Therapy for Coxal Bone Metastasis. Int J Radiat Oncol Biol Phys. 2018; 100(1): 159–161.
- De Bruycker A, Spiessens A, Dirix P, et al. Surveillance or Metastasis-Directed Therapy for Oligometastatic Prostate Cancer Recurrence: A Prospective, Randomized, Multicenter Phase II Trial. J Clin Oncol. 2018; 36(5): 446–453.
- Phillips R, Shi WY, Deek M, et al. Outcomes of Observation vs Stereotactic Ablative Radiation for Oligometastatic Prostate Cancer: The ORIOLE Phase 2 Randomized Clinical Trial. JAMA Oncol. 2020; 6(5): 650–659.
- Mazzola R, Francolini G, Triggiani L, et al. Metastasis-directed Therapy (SBRT) Guided by PET-CT 18F-CHOLINE Versus PET-CT 68Ga-PSMA in Castration-sensitive Oligorecurrent Prostate Cancer: A Comparative Analysis of Effectiveness. Clin Genitourin Cancer. 2020.