Table 2.
Summary of all 40 selected papers.
| Authors, Ref | Type of PET Analysis | SoR | Agreement between PET and SoR | Cut-Offs | Median Follow-Up (Range) | Survival Analysis | Outcome |
|---|---|---|---|---|---|---|---|
| Incerti et al. [13] | qualitative and semiquantitaive (SUVmax, MTV) | PSA | NA | MTV60 = 0.64 | 29 months (4–98) | MTV40, MTV50 and MTV60 correlated with OS; MTV60 correlated with recurrence | MTV60 and the presence of choline uptake outside the pelvic region were prognostic indicators of recurrence |
| Pasqualetti et al. [16] | qualitative | PSA | NA | NA | NA | systemic-therapy-free survival at 6, 12 and 24 months were 93.5%, 73.9%, 63.1% | [18F]Cho PET/CT can identify oligometastatic PCa suitable for SBRT, resulting in a systemic-therapy-FS of 39.1 months |
| Fodor et al. [9] | qualitative | PSA | NA | NA | 36 months (9–116) | Extra- vs. intrapelvic LNs involvement and number of PET positive LNs predicts death | Extrapelvic positive LN location and number of positive LNs predicted the clinical relapse |
| Bouman-Wammes et al. [17] | qualitative | NA | NA | NA | 2.6 years | Median ADT-free survival was 15.6 months for the whole group, and 25.7 months for patients with a PSA response | SBRT can safely and effectively be used to postpone ADT in patients with oligometastatic recurrence of PCa detected by PET/CT |
| Incerti et al. [15] | qualitative | PSA | NA | NA | 2 years (1–7) |
Complete or partial biochemical response occurred in 79% of patients, at 6 months in 82% and at 12 months in 63% of patients. bRFS at 2 years was 50%. OS at 2 years was 55% | CHO-PET/CT based HTT is a suitable therapeutic approach in patients with recurrent PCa presenting bone metastases |
| Franzese et al. [18] | qualitative (PERCIST) | PSA | NA | NA | 29.4 months (2.9–79.5) | The 1- and 2-year PFS were 55.2% and 35.1%, respectively.The 1- and 2- year treated metastasis control was 79.6% and 74.9%, respectively. | PET is important in identification of gross tumor and evaluation of the response: median PSA-nadir after the end of the RT was 1.02 ng/mL |
| Schlenter et al. [28] | Semiquantitative (T/B choline uptake ratio > 2) | PSA | NA | NA | 66 months | The 5-year overall survival was 100% in the SIB vs. 88% in the conventional group | The 5-year biochemical tumor control was 92% vs. 85% in the SIB vs. conventional groups |
| Kalinauskaite et al. [19] | Semiquantitative (SUVmedian 6) | NA | NA | NA | 34 months (5–70) | Median PFS was 12 months (range: 2–63) and TFFS was 14 months (range: 2–70). 64% patients had repeat oligometastatic disease. 48% patients with progression underwent a second SBRT course. Two-year LC after SFRS was 96%. | For patients with OMPCa, PSMA-guided SBRT might be used as an alternative to ADT, deferring the start/ escalation of palliative ADT and its side effects. Metastases treated with PSMA-PET/CT-based SFRS reached excellent LC with minimal toxicity |
| Hurmuz et al. [20] | qualitative | NA | NA | NA | 22.9 months | The 2-year OS rate was 87.6% and the median OS was not reached. The 2-year PFS rate was 63.1% and median PFS was 39.3 months. At a median of 17.9 months (2.1–24.3 months) after completion of MDT, 9 patients (0.5%) had local recurrence at the oligometastatic site. The 1- and 2-year LC rates at the treated oligometastatic site per patient were 98.1% and 93.2%, respectively. | [68Ga]PSMA-11 PET/CT-based MDT leads to excellent local control rates. Together with effective systemic management, it has the potential to contribute to achieving long-term survival in selected patients |
| Oehus et al. [14] | qualitative | PSA | NA | NA | 16 months (3–54) | OS was 97.4% after 2 years. Median bRFS was 17.0 months (14.2–19.8). After 12 months, 55.3% were free of biochemical progression. Concurrent ADT was the most important independent factor for bRFS (p = 0.01). Exploratory statistical analyses estimated a median ADT- FS of 34.0 months. | PSMA - PET-based RT for recurrent PCa with limited tumor burden was effective and safe |
| Onal et al. [21] | qualitative | PSA | NA | NA | 27.3 months | The 2-year PCSS and PFS rates were 92.0% and 72.0%, respectively. | SBRT is an efficient and well-toleratedtreatment option for PCa patients with 5 bone-only oligometastases or fewer detected with [68Ga]PSMA-11 PET/CT |
| Bergamin et al. [31] | Semiquantitavie (MTV with MRI delineation of GTV) | Histopathology | 100% | NA | 25 months | Twenty-four patients had a 12-months [68Ga]PSMA-11 PET/CT, 23 (92%)with no evidence of disease. Ten of the 12 patients with routine 24-month [68Ga]PSMA-11 PET/CTs were disease free. The 2-year bFFF estimated was 79.6%. |
PSMA-directed salvage focal reirradiation to the prostate using linear accelerator based SBRT is feasible and safe |
| Henkenberens et al. [22] | qualitative | PSA | NA | not for PET | 39.5 months (18–60) | Median bPFS_1 was 16.0 months after the first PSMA PET-directed RT and the median bPFS_2 was 8.0 months after the second PSMA PET-directed RT. Median ADT-FS was 31.0 months | Repeated PSMA PET-directed RT for oligorecurrent PCa postponed ADT without significant toxicities |
| Emmet et al. [10] | qualitative and semiquantitative(SUVmax) | PSA | NA | NA | 38 months (IQR 31–43) | FFP at 3 years in 64.5% of men who underwent sRT. 3 years FFP was 81% in those with negative or fossa-confined findings; 45% in PSMA PET–positive disease outside the prostatic fossa. | PSMA PET results are highly predictive of FFP at 3 years in men undergoing sRT for BCR after RP Negative PSMA PET results or disease identified as still confined to the prostatic fossa demonstrated high FFP |
| Shakespeare et al. [29] | NA | NA | NA | NA | 24 months (10–50) | Two-year failure-free survival was 100%, and two-year overall survival 95.7% | PSMA PET-guided IMRT up to 81 Gy to the prostate and involved LNs, and long term ADT, is a promising approach for newly diagnosed LN positive PCa |
| Narang et al. [30] | GTV | NA | NA | 63.5 months (17–92) | 5 years PFS was 88.2%, biochemical PFS was 91.4% and OS was 96.9% | Excellent five-year outcomes can be obtained even for locally advanced, node-positive and bone oligometastatic PCa, by means of dose-escalation using EH-SBRT boost to the prostate | |
| Baumann et al. [23] | qualitative PERCIST | PSA | NA | reduction in SUVmax of at least 30% with no increase in lesion size. | 11 months (2–15) | PFSl of 88% after 1 year | PSMA PET-detected metastatic lesions can be effectively treated with high-precision radiotherapy to the PSMA PET-positive tumor volume |
| Artigas et al. [24] | qualitative | PSA | NA | NA | 15 months (4–33) | BCR-free survival rate at 1 year was 79% and 53% at 2 years. ADT-free survival at 2 years was 74%. | Metastasis-directed RT based on [68Ga]PSMA-11 PET/CT may be a valuable treatment in patients with PCa oligometastatic disease, providing promising BCR-free survival rates and potentially postponing ADT for at least 2 years in 74% of the patients |
| Guler et al. [25] | Semiquantitative (SUVmax) | PSA | NA. | NA | 7 months (2–17) | The actuarial 1-year LC, PFS and OS rates were 100, 51 (95% CI 8–83%) and 100%. | PSMA PET-CT-guided RT may be an attractive treatment strategy in patients with oligo-metastatic PCa providing optimal LC, low toxicity and a promising PFS |
| Emmet et al. [11] | qualitative and semiquantitative(SUVmax) | PSA | 50% | NA | 10.5 months (IQR 6–14) | Overall treatment response after SRT was 72%. 45% of patients with a negative PSMA underwent SRT whereas 55% did not. In men with a negative PSMA who received SRT, 85% demonstrated a treatment response, compared with a further PSA increase in 65% in those not treated. | PSMA PET is independently predictive of treatment response to SRT and stratifies men into a high treatment response to SRT (negative or fossa-confined PSMA) versus men with poor response to SRT (nodes or distant-disease PSMA) |
| Schmidt-Hegemann et al. [12] | qualitative | PSA | 74% | NA | 20 months (3–42) | 94% of patients with biochemical recurrence and 82% of patients with biochemical persistence having a PSA ≤ 0.2 ng/ml. | PSMA PET/CT-based radiotherapy is an effective local salvage treatment option with significant PSA response in patients with biochemical recurrence or persistence after radical prostatectomy leading to deferral of long-term ADT or systemic therapy |
| Henkenberens et al. [26] | qualitative - CTV PET based | PSA | NA | NA | 39 months | The median bPFS was 12.0 months after PSMA ligand PET-based RT and the median SST-FS was 15.0 months. | PSMA PET-guided RT represents a viable treatment option for patients with oligometastatic mCRPCa to delay further systemic therapies |
| Koerber et al. [27] | qualitative and semiquantitative(SUVmax) | PSA | 83.1% | NA | 26 months | 3-years OS and bPFS were 84% and 55%, respectively. The median time of ADT-free survival was 13.5 months | PSMA-guided RT is a promising therapeutic approach in guiding to RT in OMD |
| Schwarzenbock et al. [33] | Semiquantitative (SUVmax and SUVmean) | RECIST | 30% | NA | NA | NA | No correlation among PSA, RECIST and SUVs by choline PET |
| Ceci et al. [35] | EORTC criteria | PSA | 47.5% disagreement | none | 13.5 months (6–53) | increasing PSA trend after docetaxel predicts PD | PET/CT identified PD despite PSA response. Tumor burden at baseline predicted PD |
| Schwarzenböck et al. [34] | semiquantitative | Histopathology | 91% | none | NA | NA | Decrease in choline uptake after combined neoadjuvant therapy are paralleled by regressive and apoptotic changes in histopathology |
| Quaquarini et al. [36] | Semiquantitative (SUVmax, SUVmean, PVC-SUV, MATV, TLA, PVC-TLA). Whole-body indices | NA | NA | SMATV value > 27 cc | 6 years | SMATV, and STLA had a statistically significant correlation with PFS | Semi-quantitative indexes such as SMATV and STLA at baseline have a prognostic role in patients treated with docetaxel |
| Seitz et al. [37] | qualitative (PERCIST) | CT | 50–86% | NA | NA | NA | [68Ga]PSMA-11 PET is a promising tool for the assessment of response to therapy |
| Anton et al. [38] | qualitative and semiquantitative (SUVmax, MTV, total lesional PSMA-expression) | PSA, CT | 100% | NA | 37.7 months | NA | PSMA PET/CT response by visual analysis is concordant with the established good prognostic marker of PSA ≤ 0.2 ng/mL following chemo-hormonal therapy, and may be a better predictor of CRPCa |
| Has Simsek et al. [39] | Semiquantitative (SUVmax, SUVmean, TV-PSMA, TL-PSMA) | PSA | sensitivity: 75% and specificity 80% | TV-PSMA 107 cm3 and TL-PSMA 1013 cm3 | 60 months | The median TTP was 16 months, and the median OS was not reached. High TV-PSMA, highTL-PSMA, high age, and high LDH were associated with shorter OS, while high TV-PSMA and high age were significantly related with shorter TTP. | Patients with high TV-PSMA had a significantly higher risk for chemotherapeutic failure. PSMA-based tumor burden prior chemotherapy seems to be a reliable predictive tool for survival in mCRPCa patients. |
| Caffo et al. [40] | EORTC criteria | PSA | 50% | NA | NA | no | FCH PET/CT could assess the effect of enzalutamide in extensive PCa disease |
| Maines et al. [41] | EORTC criteria | PSA | 20/30 | NA | 16.5 months (2.9–18.9) | baseline SUVmax was correlated with BCR | baseline PET/CT can be useful to define patients who will benefit from enzalutamide after docetaxel |
| De Giorgi et al. [43] | qualitative | PSA | 71% | NA | 22 months | progression PET, PFS: 3.4 months non-progression PET, PFS: 12.8 months | Association of FCH PET and PSA can improve the prediction of outcome and to monitor the response to therapy in mCRPCa |
| De Giorgi et al. [42] | qualitative | PSA | 71% | NA | 24.2 months (1.8–27.3) | PET/CT (DC or PD) predicted only PFS | Association of FCH PET and PSA can improve the prediction of outcome and to monitor response to therapy in mCRPCa |
| Chen et al. [44] | semiquantitative (SUVmax and MTV) | Histopathology | Specificity: 89% | NA | NA | NA | [68Ga]PSMA-11 PET/CT has a better diagnostic performance of pathological response to neoadjuvant treatment compared with PSA |
| Zukotynski et al. [45] | semiquantitative (SUVmax, DPSM, DASM) | Conventional imaging and RECIST 1.1 | NA | NA | 28.2 months | low DPSM had median TTTC 12.2 months and median OS 37.2 months; high DPSM had median TTTC 6.5 months and median OS 17.8 months. Low DASM had median TTTC 12.2 months and median OS. High DASM had median TTTC 6.9 months and median OS 17.8 months. |
Findings on PSMA-targeted PET 2–4 months after initiation of abiraterone or enzalutamide is associated with TTTC and OS |
| Plouznikof et al. [46] | Dominant response criteria, SUVmax | PSA | NA. | NA | 3 months | NA | PSMA PET/CT response evaluation is strongly associated with response to treatment in mCRPCa patients under enzalutamide or abiraterone |
| Filippi et al. [47] | qualitative and TLA variations analysis | clinical, laboratory, imaging | 100% | 50% TLA (TLG) reduction |
NA | median OS TLA-responder 19 vs. 8 months TLA-non-responders | Reduction in [18F]Cho PET/CT TLA after 223Ra seems to be related to longer survival |
| García Vicente et al. [48] | qualitative and semiquantitative (SUV max, average SUVmax for the five referred lesions) | PSA | NA | NA | NA | The extension of the bone disease by FCH PET/CT, SUVmax and average SUVmax were related to OS. No significant association was found for the PFS. | FCH PET/CT had a prognostic role in the prediction of OS. None clinical or imaging variable were able to predict the PFS |
| Ahmadzadehfar et al. [49] | qualitative | Bone scan, PSA, ALP | Significant correlation | NA | NA | NA | Improved therapeutic response in patients who underwent PSMA PET/CT as a gatekeeper for 223Ra therapy, because of better patient selection, mainly with the exclusion of patients with bone marrow involvement |
NA = not available; MTV = metabolic tumor volume; OS = overall survival; FS = free survival; SBRT: stereotactic body radiation therapy; LN = lymph node; ADT = androgen deprivation therapy; PCa = prostate cancer; bRFS = biochemical recurrence free survival; HTT = hormonal therapy time; RT = radiation therapy; SIB = simultaneous integrated boost;T/B = tumor to background, PFS = progression free survival; TFFS = time to free survival; LC = local control; SFRS = single fraction radio-surgery; OMPC = oligometastatic prostate cancer; PD = progressive disease; PCSS = prostate cancer specific survival; MRI = magnetic resonance imaging; GTV = gross tumor volume; mCRPC = metastatic castrate resistant prostate cancer; FFP = free from progression; PVC = partial volume effect; MATV = metabolic activity tumor volume; TLA = total lesion activity; TL = total lesion; TV = total volume; DPSM = delta percentage of SUVmax; DASM = delta absolute of SUVmax.