PEACE V-Salvage Treatment of OligoRecurrent nodal prostate cancer Metastases (STORM): Acute Toxicity of a Randomized Phase 2 Trial.

BACKGROUND: Treatment recommendations for patients with limited nodal recurrences are lacking, and different locoregional treatment approaches are currently being used. OBJECTIVE: The aim of this trial is to compare metastasis-directed therapy (MDT) with or without elective nodal pelvic radiotherapy (ENRT). DESIGN, SETTING, AND PARTICIPANTS: PEACE V-Salvage Treatment of OligoRecurrent nodal prostate cancer Metastases (STORM) is an international, phase 2, open-label, randomized, superiority trial (ClinicalTrials.gov identifier: NCT03569241). Patients diagnosed with positron emission tomography-detected pelvic nodal oligorecurrence (five or fewer nodes) following radical local treatment for prostate cancer were randomized in a 1:1 ratio between arm A (MDT and 6 mo of androgen deprivation therapy [ADT]) and arm B (ENRT [25 × 1.8 Gy] with MDT and 6 mo of ADT). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We report the secondary endpoint acute toxicity, defined as worst grade ≥2 Common Terminology Criteria for Adverse Events v4.0 gastrointestinal (GI) or genitourinary (GU) toxicity within 3 mo of treatment. The chi-square test was used to compare toxicity between treatment arms. We also compare the quality of life (QoL) using the European Organisation for Research and Treatment of Cancer QLQ C30 and PR25 questionnaires. RESULTS AND LIMITATIONS: Between June 2018 and April 2021, 196 patients were assigned randomly to MDT or ENRT. Ninety-seven of 99 patients allocated to MDT and 93 of 97 allocated to ENRT received per-protocol treatment. Worst acute GI toxicity proportions were as follows: grade ≥2 events in three (3%) in the MDT group versus four (4%) in the ENRT group (p = 0.11). Worst acute GU toxicity proportions were as follows: grade ≥2 events in eight (8%) in the MDT group versus 12 (13%) in the ENRT group (p = 0.95). We observed no significant difference between the study groups in the proportion of patients with a clinically significant QoL reduction from baseline for any subdomain score area. CONCLUSIONS: No clinically meaningful differences were observed in worst grade ≥2 acute GI or GU toxicity or in QoL subdomains between MDT and ENRT. PATIENT SUMMARY: We found no evidence of differential acute bowel or urinary side effects using metastasis-directed therapy and elective nodal radiotherapy for the treatment of patients with a pelvic lymph node recurrence.

Lymphocyte-sparing pelvic radiotherapy for prostate cancer: An in-silico study.

Background and Purpose: Evidence regarding radiation-induced lymphopenia and its negative impact on oncological outcome is incrementing. Therefore, the aim of this study is to evaluate the feasibility of lymphocyte-rich organs at risk (LOAR) sparing in pelvic irradiation for localized prostate cancer and to estimate its impact on the effective dose to circulating immune cells (EDIC). Materials and Methods: Twenty patients with pelvic nodal and prostate or prostate bed irradiation were included. The following bone marrow (BM) structures were delineated as LOARs using semi-automatic segmentation: lumbosacral spine (Ls-BM), ilium (Il-BM), lower pelvis (Lp-BM), and the combined whole-pelvis (Wp-BM). Twenty new lymphocyte sparing treatment plans (LS plans) were calculated, optimizing doses to LOARs while maintaining strict coverage of the targets and respecting standard OARs dose constraints. Finally, we elaborated an EDIC calculation model for pelvic irradiation. Results: LS plans showed a statistically significant dose decrease for LOAR compared to standard of care plans without compromising target coverage nor classic OAR dose constraints: in prostate plans, the V40Gy for Ls-BM, Il-BM, and Lp-BM was decreased by 23 %, 36 %, 52 % respectively. For prostate bed plans, the V40Gy for Ls-BM, Il-BM, and Lp-BM was decreased by 25 %, 59 %, 56 %, respectively. For Wp-BM, the V10Gy, V20Gy, and Dmean have been decreased by 3 %, 14 %, 15 %, and by 5 %, 15 %, 17 %, respectively for prostate and prostate bed plans. A statistically significant decrease in EDIC was seen for LS plans in both groups. Conclusions: We successfully demonstrated the feasability of lympocyte-sparing treatment planning in pelvic irradiation, also proposing a model for EDIC calculation.

Oligorecurrent nodal prostate cancer: Radiotherapy quality assurance of the randomized PEACE V-STORM phase II trial.

PURPOSE: Aim of this study is to report the results of the radiotherapy quality assurance program of the PEACE V-STORM randomized phase II trial for pelvic nodal oligorecurrent prostate cancer (PCa). MATERIAL AND METHODS: A benchmark case (BC) consisting of a postoperative case with 2 nodal recurrences was used for both stereotactic body radiotherapy (SBRT, 30 Gy/3 fx) and whole pelvic radiotherapy (WPRT, 45 Gy/25 fx + SIB boost to 65 Gy). RESULTS: BC of 24 centers were analyzed. The overall grading for delineation variation of the 1st BC was rated as 'UV' (Unacceptable Variation) or 'AV' (Acceptable Variation) for 1 and 7 centers for SBRT (33%), and 3 and 8 centers for WPRT (46%), respectively. An inadequate upper limit of the WPRT CTV (n = 2), a missing delineation of the prostate bed (n = 1), and a missing nodal target volume (n = 1 for SBRT and WPRT) constituted the observed 'UV'. With the 2nd BC (n = 11), the overall delineation review showed 2 and 8 'AV' for SBRT and WPRT, respectively, with no 'UV'. For the plan review of the 2nd BC, all treatment plans were per protocol for WPRT. SBRT plans showed variability in dose normalization (Median D90% = 30.1 Gy, range 22.9-33.2 Gy and 30.6 Gy, range 26.8-34.2 Gy for nodes 1 and 2 respectively). CONCLUSIONS: Up to 46% of protocol deviations were observed in delineation of WPRT for nodal oligorecurrent PCa, while dosimetric results of SBRT showed the greatest disparities between centers. Repeated BC resulted in an improved adherence to the protocol, translating in an overall acceptable contouring and planning compliance rate among participating centers.

Oligometastatic Disease Detection with 68Ga-PSMA-11 PET/CT in Hormone-Sensitive Prostate Cancer Patients (HSPC) with Biochemical Recurrence after Radical Prostatectomy: Predictive Factors and Clinical Impact.

Metastasis-directed therapy (MDT) in oligometastatic prostate cancer has the potential of delaying the start of androgen deprivation therapy (ADT) and disease progression. We aimed to analyze the efficacy of PSMA-PET/CT in detecting oligometastatic disease (OMD), to look for predictive factors of OMD, and to evaluate the impact of PSMA-PET/CT findings on clinical management. We retrospectively analyzed a homogeneous population of 196 hormone-sensitive prostate cancer patients (HSPC), considered potential candidates for MDT, with a PSMA-PET/CT performed at biochemical recurrence (BCR) after radical prostatectomy (RP). Multivariable logistic regression analysis was performed based on several clinico-pathological factors. Changes in clinical management before and after PSMA-PET/CT were analyzed. The OMD detection rate was 44% for a total positivity rate of 60%. PSMA-PET/CT positivity was independently related to PSA (OR (95% CI), p) (1.7 (1.3-2.3), p < 0.0001) and PSAdt (0.4 (0.2-0.8), p = 0.013), and OMD detection was independently related to PSA (1.6 (1.2-2.2), p = 0.001) and no previous salvage therapy (0.3 (0.1-0.9), p = 0.038). A treatment change was observed in 58% of patients, mostly to perform MDT after OMD detection (60% of changes). This study showed that PSMA-PET/CT is an excellent imaging technique to detect OMD early in HSPC patients with BCR after RP, changing therapeutic management mostly into MDT.

Evaluation of the XVI dual registration tool for image-guided radiotherapy in prostate cancer.

PURPOSE: To compare the reliability and the required time for two cone-beam CT (CBCT) registration methods for prostate irradiation (PI) and prostate bed irradiation (PBI). MATERIAL AND METHODS: Two-hundred treatment fractions (in 10 PI and 10 PBI patients) were reanalyzed, using two CBCT registration methods: (1) a combination of an automated chamfer matching (CM) with manual matching (MM), and (2) the automated XVI dual registration tool (DRT). Bland-Altman 95% Limits of Agreement (LoA) were used to assess agreement with manual registration by Radiation Oncologists. RESULTS: All 95% LoA for CM + MM were ≤ 0.33 cm. For DRT, several 95% LoA were notably larger than the predefined clinical threshold of 0.3 cm: -0.47 to +0.25 cm (PI) and -0.36 to +0.23 cm (PBI) for the superior-inferior direction and -0.52 to +0.24 cm (PI) and -0.38 to +0.31 cm (PBI) for the anterior-posterior direction.For PI, the average time required was 33 s with CM + MM versus only 18 s with DRT (p = 0.002). For PBI, this was 13 versus 19 s, respectively (p = 0.16). CONCLUSION: For PI, DRT was significantly faster than CM + MM, but the accuracy is insufficient to use without manual verification. Therefore, manual verification is still warranted, but could offset the time benefit. For PBI, the CM + MM method was faster and more accurate.

Phase II open-label study investigating apalutamide in patients with biochemical progression after radical prostatectomy.

Apalutamide, a competent inhibitor of the androgen receptor, has shown promising clinical efficacy results for patients with advanced prostate cancer. Here, we describe the rationale and design for the SAVE trial, a multi-center, Phase II study, wherein 202 men with biochemical progression after radical prostatectomy are randomly assigned 1:1 to apalutamide plus salvage radiotherapy (SRT) or androgen-deprivation therapy with an luteinizing hormone-releasing hormone agonist or antagonist plus SRT. The primary objective is to compare sexual function between the two treatment arms based on the expanded prostate cancer index-26 sexual domain score at nine months after start of hormonal treatment. The key secondary objectives are to assess quality of life, to evaluate the safety profile and the short-term efficacy of apalutamide in combination with SRT. ClinicalTrials.gov identifier: NCT03899077.

Vertebral Hemangioma Mimicking Bone Metastasis in 68Ga-PSMA Ligand PET/CT.

Ga-PSMA PET/CT was performed in a 68-year-old man to evaluate recurrent prostate cancer due to elevated serum prostate-specific antigen level. Images showed a focal uptake in the prostatic gland, suggesting local relapse, and an intense uptake in the 12th thoracic vertebra, with no morphological abnormalities in CT slices. In order to confirm extraprostatic disease and before radiotherapy planning, a full-spine MRI was performed, resulting with the morphological pattern of a vertebral hemangioma. Hystological analysis confirmed the local relapse in the prostate. No radiotherapy treatment was given to the vertebra, and after 1 year of follow-up without systemic treatment, prostate-specific antigen is still undetectable.

Clinical impact of 68 Ga-prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) in patients with prostate cancer with rising prostate-specific antigen after treatment with curative intent: preliminary analysis of a multidisciplinary approach.

OBJECTIVE: To assess the impact of a novel molecular imaging technique, 68 Ga-(HBED-CC)-prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT), in the clinical management of patients with prostate cancer with rising prostate-specific antigen (PSA) after treatment with curative intent. PATIENTS AND METHODS: In all, 131 consecutive patients were referred to our centre for a 68 Ga-PSMA PET/CT in the setting of recurring prostate cancer. Of these patients, 11/131(8%) presented with persistent PSA after radical prostatectomy, while 120/131 (92%) were referred for biochemical recurrence after surgery, radiotherapy or both. The images where taken 1 h after injection of 2 MBq/kg of the 68 Ga-(HBED-CC)-PSMA ligand. All examinations were interpreted by two experienced nuclear medicine specialists. Using the results of the examination, a multidisciplinary oncology committee (MOC) reported on the treatment strategy. A positive impact on clinical management was considered if the examination determined a modification in the treatment strategy compared to the MOC decision before PSMA imaging. RESULTS: All patients completed the examination with no adverse reactions. The median (interquartile range) PSA level at the time of the examination was 2.2 (0.72-6.7) ng/mL. Overall, 68 Ga-PSMA PET/CT detected at least one lesion suspicious for prostate cancer in 98/131 (75%) patients. There was an impact on subsequent management in 99/131 patients (76%). The main modifications included continuing surveillance (withholding hormonal therapy), hormonal manipulations, stereotaxic radiotherapy, salvage radiotherapy, salvage node dissection or salvage local treatment (prostatectomy, high-intensity focussed ultrasound). CONCLUSION: Our preliminary experience suggests that performing 68 Ga-PSMA PET/CT in patients with prostate cancer with rising PSA after treatment with curative intent can be clinically useful as it changes the treatment strategy in a significant proportion of patients. However, larger prospective trials are needed to validate our present findings.