Effect of Serelys Homme on the Incidence and Severity of Vasomotor Symptoms and Quality-of-Life Impairments in Patients Receiving Hormone Therapy and Radiation for Localized Prostate Cancer: Results of the ESCULAPE Phase 2 Prospective Study.

Purpose: Androgen deprivation therapy (ADT) may cause vasomotor symptoms (VMS) including hot flushes and sweats, which affect quality of life (QoL). Serelys Homme is a nonhormonal and a natural origin product that could affect VMS in men undergoing ADT. We evaluated effectiveness and tolerance of Serelys Homme administration on VMS and QoL of patients undergoing combined ADT and radiation therapy for prostate cancer. Methods and Materials: Between April 2017 and July 2019, 103 patients were screened, and 53 patients refused to participate in the study. Serelys Homme therapy consisted of a daily administration of 2 tablets for 6 months. Patients were evaluated with 4 questionnaires including the adapted Modified Rankin Scale (adapted-MRS), European Quality of Life 5 Dimensions 3 Level Version (EQ 5D3L), Functional Assessment of Cancer Therapy-Prostate (FACT-P), and Hot Flash Related Daily Interference Scale (HFRDIS) at day 0, day 90 (D90), and day 180 (D180). Statistical evaluation was performed using the Wilcoxon rank sign test. A 2-sided P < .05 was considered statistically significant. Results: Among the 50 patients, 4 withdrew after inclusion. All patients (n = 46) received either postoperative or definitive radiation therapy combined with a short (n = 15) or long course (n = 31) of ADT. Serelys Homme administration significantly decreased the rate of patients who had ≥7 VMS and 3 to 6 VMS per day. The number of patients presenting with moderate or severe VMS was decreased at D90 (P = .005) and at D180 (P = .005). In addition, VMS duration was reduced at D90 (P = .002) and D180 (P < .001). Finally, at D90 and D180, 11.1% and 16.0% of patients, respectively, with initial severe or moderate VMS had a complete response without further symptoms. Among QoL parameters, fatigue decreased significantly. Effectiveness evaluated by doctors was rated as moderate or good to excellent VMS control in 20% and 60% of the patients, respectively. No side effects were recorded in the whole population. Conclusions: This study demonstrated effectiveness and excellent tolerance of Serelys Homme. We observed a significant reduction of the frequency, duration, and intensity of hot flushes and sweats induced by ADT. Serelys Homme increased QoL scores. These encouraging results open the prospect to further studies and Serelys Homme use in patients undergoing ADT for prostate cancer.

Effect of lethal total body irradiation on bone marrow chimerism, acute graft-versus-host disease, and tumor engraftment in mouse models: impact of different radiation techniques using low- and high-energy X-rays.

PURPOSE: Effects of X­ray energy levels used for myeloablative lethal total body irradiation (TBI) delivery prior to bone marrow transplantation (BMT) in preclinical mouse models were examined. MATERIALS AND METHODS: In mouse models, single-fraction myeloablative TBI at a lethal dose was delivered using two different X­ray devices, either low (160 kV cabinet irradiator) or high energy (6 MV linear accelerator), before semi-allogeneic hematopoietic stem-cell transplantation (HSCT) to ensure bone marrow (BM) chimerism, graft-versus-host disease (GVHD), and tumor engraftment. Recipient mice were clinically followed for 80 days after bone marrow transplantation (BMT). Flow cytometry was performed to assess donor chimerism and tumor engraftment in recipient mice. RESULTS: Both X­ray irradiation techniques delivered a 10 Gy single fraction of TBI, presented a lethal effect, and could allow near-complete early donor chimerism on day 13. However, low-energy irradiation increased T cells' alloreactivity compared to high-energy irradiation, leading to clinical consequences for GVHD and tumor engraftment outcomes. The alloreactive effect differences might be attributed to the distinction in inflammatory status of irradiated recipients at donor cell infusion (D0). Delaying donor cell administration (D1 after lethal TBI) attenuated T cells' alloreactivity and clinical outcomes in GVHD mouse models. CONCLUSION: Different X­ray irradiation modalities condition T cell alloreactivity in experimental semi-allogeneic BMT. Low-energy X­ray irradiator induces a post-TBI inflammatory burst and exacerbates alloreactive reactions. This technical and biological information should be considered in interpreting GVHD/ graft-versus-leukemia effect results in mice experimental models of BMT.

Genomic Prostate Score: A New Tool to Assess Prognosis and Optimize Radiation Therapy Volumes and ADT in Intermediate-Risk Prostate Cancer.

Genomic classifiers such as the Genomic Prostate Score (GPS) could help to personalize treatment for men with intermediate-risk prostate cancer (I-PCa). In this study, we aimed to evaluate the ability of the GPS to change therapeutic decision making in I-PCa. Only patients in the intermediate NCCN risk group with Gleason score 3 + 4 were considered. The primary objective was to assess the impact of the GPS on risk stratification: NCCN clinical and genomic risk versus NCCN clinical risk stratification alone. We also analyzed the predictive role of the GPS for locally advanced disease (≥pT3+) and the potential change in treatment strategy. Thirty patients were tested for their GPS between November 2018 and March 2020, with the median age being 70 (45-79). Twenty-three patients had a clinical T1 stage. Eighteen patients were classified as favorable intermediate risk (FIR) based on the NCCN criteria. The median GPS score was 39 (17-70). Among the 23 patients who underwent a radical prostatectomy, Gleason score 3 + 4 was found in 18 patients. There was a significant correlation between the GPS and the percentage of a Gleason grade 4 or higher pattern in the surgical sample: correlation coefficient r = 0.56; 95% CI = 0.2-0.8; p = 0.005. In this study, the GPS combined with NCCN clinical risk factors resulted in significant changes in risk group.

Early Versus Late Postoperative Radiotherapy in Patients With Prostate Cancer: Results of a Single-centre Retrospective Study.

BACKGROUND/AIM: A much-debated topic relating to patients at risk of local prostate cancer recurrence, but with post-operative leveIs of prostate-specific antigen (PSA) lower than 0.2 ng/ml, concerns the best timing of postoperative radiotherapy (RT), adjuvant or salvage? The present monocentric, retrospective study aimed to investigate the best PSA value at which to plan salvage RT for patients with recurrent prostate cancer. PATIENTS AND METHODS: From January 2011 to December 2019, 158 patients were treated with adjuvant RT at Pisa University Hospital, whilst 91 patients underwent salvage RT. We grouped the patients treated with salvage RT using their PSA values at the time of salvage RT: PSA >0.5 ng/ml, PSA between 0 and 0.5 ng/ml, and PSA ≤0.2 ng/ml. The median follow-up was 63 months. Biochemical recurrence-free survival (BFS) measured from surgery was the primary endpoint. RESULTS: Salvage RT led to shorter BFS compared to adjuvant RT considering the whole cohort of patients, with a hazard ratio of 3.195 (95% confidence interval=1.534-6.655, p=0.002). However, analysing only the group of patients with PSA ≤0.2 ng/ml at the time of salvage RT, salvage RT led to BFS similar to that achieved with adjuvant RT (p=0.35). CONCLUSION: Our results suggest that when scheduled for patients with a PSA ≤0.2 ng/ml, salvage RT results in equivalent biochemical control to that with adjuvant RT.

Radiation Therapy Delivery Challenges in Older Patients During Coronavirus Disease 2019 Pandemic.

PURPOSE: The management of older patients in radiation therapy (RT) departments has been challenging in the context of the Coronavirus Disease 2019 (COVID-19) outbreak. We report our experience of RT adapted schedules or strategy changes in older patients during the COVID-19 pandemic. METHODS AND MATERIALS: Patients aged ≥75 years were recruited during weekly chart rounds. All were potentially eligible for a specific intervention to reduce the frequency of patients' visits to the hospital. The effect of deferring radiation and hypofractionation of RT schedules was assessed in terms of the number of courses initially planned and replanned during the lockdown. RESULTS: Twenty patients were identified during the official lockdown in France (March 17 to May 11). Median age was 78 years (75-95 years). Most patients were male (n = 12, 60%) being treated in the postoperative setting (n = 17, 85%). RT was delayed in 11 cases (55%) with hormonal therapy prescribed in 10 cases (50%). Altered RT fractionation was proposed for 5 cases (25%); combinations of altered fractionation and deferral of radiation were applied in 3 cases (15%). The number of radiation courses initially planned and replanned according to the pandemic context: 563 and 197, respectively (-62%; P < .001). None presented recurrence when RT was initiated, and no patient developed symptomatic COVID-19 infection. CONCLUSIONS: In the context of the COVID-19 outbreak, individual risk-based radiation therapy seems to be safe. Systematic screening of patients for COVID-19 before starting radiation therapy is mandatory. In our department the oncogeriatrics expertise availability for daily practice was of great use during the pandemic. Other prospective studies are needed to validate such strategies in case of resurgence of similar outbreaks.

Hemostatic radiotherapy for bladder cancer-related hematuria in patients unfit for surgery: is there any impact of fractionation schedule?

PURPOSE: The optimal schedule for palliative external beam radiotherapy (EBRT) in patients with bladder tumors with hematuria unfit for surgery remains undefined. This study aimed to assess the clinical hemostatic efficacy and safety of two EBRT hypofractionated schedules. METHODS: From February 2008 to October 2017, 31 patients were referred to our department for palliative hemostatic bladder irradiation. EBRT consisted of two schedules: "continuous" treatment (CRT) was delivered following consecutive 3-10 weekdays (3-6Gy/fraction (fr), to a total dose of 18-30Gy) (n=14); the "discontinuous" schedule (DRT) consisted of 23Gy in 4fr (6.5Gy/fr on days 1 and 3, followed by 5Gy/fr on days 15 and 17; n=12). The primary endpoint was the rate of hemostatic control (HC) at the end of the radiation course. Other endpoints included mid-term HC, toxicities and overall survival. Comparative analyses were performed by exact Fisher test with a cut-off of 0.05 for statistical significance. RESULTS: The rate of HC at the end of EBRT was 92% (n=24) with no differences between CRT and DRT (100% vs 86%; p=0.48). The median follow-up was 6 months, HC was achieved in 15/26 (58%) patients at the last follow-up, without meaningful differences between CRT and DRT (50% vs 67%; p=0.45). Three and two patients developed acute grade ≤2 diarrhea in CRT and DRT groups, respectively. CONCLUSION: Our study suggests that both hypofractionated "continuous" and "discontinuous" EBRT are well tolerated and represent acceptable schedules for patients with limited life expectancy. DRT schedule could be preferred for departments' organization to increase the slots for the treatment of other referred patients for radiotherapy.

Radiation Therapy Department Reorganization during the Coronavirus Disease 2019 (COVID-19) Outbreak: Keys to Securing Staff and Patients During the First Weeks of the Crisis and Impact on Radiation Therapy Practice from a Single Institution Experience.

PURPOSE: During the first weeks of the coronavirus disease 2019 (COVID-19) outbreak in France, it was necessary to clearly define organizational priorities in the radiation therapy (RT) departments. In this report, we focus on the urgent measures taken to reduce risk for both our staff and patients by reducing the number of patients receiving treatment. METHODS AND MATERIALS: We reviewed the fractionation schemes for all patients in our department, including those receiving treatment and those soon to start treatment. Our goals were to (1) decrease the number of patients coming daily to the hospital for RT, (2) adapt our human resources to continue patients' care in the department, and (3) help to cover understaffed COVID-19 sectors of the hospital. RESULTS: We identified 50 patients who were receiving treatment (n = 6), were going to start radiation after CT scan simulation (n = 41), or for whom the CT scan was pending (n = 3). The majority were women (64%) treated for breast cancer (54%). RT was delayed for 22 (44%) patients. The majority were offered hormone therapy as "waiting therapy." Hypofractionation was considered in 21 (42%) patients mainly with breast cancer (18 of 21, 86%). The number of courses initially planned and replanned as a result of the COVID-19 outbreak during the period of March 15 to May 31, 2020, were 1383 and 683, respectively, which represented a reduction of 50% (including delayed sessions) that allowed our reorganization process. CONCLUSIONS: To conserve resources during the pandemic, we successfully reduced the number of patients receiving treatment in a proactive fashion and adapted our organization to minimize the risk of COVID-19 contamination. Departments across the world may benefit from this same approach.

A review of the international early recommendations for departments organization and cancer management priorities during the global COVID-19 pandemic: applicability in low- and middle-income countries.

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by a new virus that has never been identified in humans before. COVID-19 caused at the time of writing of this article, 2.5 million cases of infections in 193 countries with 165,000 deaths, including two-third in Europe. In this context, Oncology Departments of the affected countries had to adapt quickly their health system care and establish new organizations and priorities. Thus, numerous recommendations and therapeutic options have been reported to optimize therapy delivery to patients with chronic disease and cancer. Obviously, while these cancer care recommendations are immediately applicable in Europe, they may not be applicable in certain emerging and low- and middle-income countries (LMICs). In this review, we aimed to summarize these international guidelines in accordance with cancer types, making a synthesis for daily practice to protect patients, staff and tailor anti-cancer therapy delivery taking into account patients/tumour criteria and tools availability. Thus, we will discuss their applicability in the LMICs with different organizations, limited means and different constraints.

[18F]Fluorocholine PET/CT-guided stereotactic body radiotherapy in patients with recurrent oligometastatic prostate cancer.

BACKGROUND: In the last years, functional imaging has given a significant contribution to the clinical decision-making of biochemically relapsed prostate cancer (PCa). Hereby, we present a prospective study aiming to validate the role of [18F]Fluoro-Methyl Choline ([18F]FMCH) PET/CT in the selection of PCa patients suitable for stereotactic body radiotherapy (SBRT). METHODS: Patients with biochemical recurrence limited up to three lesions revealed by [18F]FMCH PET/CT were enrolled in the present study and treated with SBRT on all active lesions. Systemic therapy-free survival since the [18F]FMCH PET/CT was considered as the primary endpoint. RESULTS: Forty-six patients were evaluated, and a total of 67 lesions were treated. After a median follow-up of 28.9 months, systemic therapy was started in 30 patients (65.2%) and median systemic therapy-free survival was 39.1 months (95% CI 6.5-68.6); 6, 12, and 24-month ratios were 93.5%, 73.9%, and 63.1%, respectively. At univariate Cox regression analysis, Delta PSA demonstrated an impact on systemic therapy-free survival (p < 0.001). CONCLUSIONS: Based on our findings, [18F]FMCH PET/CT can identify oligometastatic prostate cancer patients suitable for SBRT, resulting in a systemic therapy-free survival of 39.1 months.

Assessing the Role and Optimal Duration of Hormonal Treatment in Association with Salvage Radiation Therapy After Radical Prostatectomy: Results from a Multi-Institutional Study.

BACKGROUND: The optimal duration of hormonal therapy (HT) when associated with postprostatectomy radiation therapy (RT) remains controversial. OBJECTIVE: To test the impact of HT duration among patients treated with postprostatectomy RT, stratified by clinical and pathologic characteristics. DESIGN, SETTING, AND PARTICIPANTS: The study included 1264 patients who received salvage RT (SRT) to the prostatic and seminal vesicle bed at eight referral centers after radical prostatectomy (RP). Patients received SRT for either rising prostate-specific antigen (PSA) or PSA persistence after RP, defined as PSA ≥0.1ng/ml at 1mo after surgery. Administration of concomitant HT was at the discretion of the treating physician. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The outcome of interest was clinical recurrence (CR) after SRT, as identified by imaging. Multivariable Cox regression analysis was used to test the association between CR and HT duration. We applied an interaction test between HT duration and baseline risk factors to assess the hypothesis that CR-free survival differed by HT duration according to patient profile. Three risk factors were prespecified for evaluation: pT stage ≥pT3b, pathologic Gleason ≥8, and PSA level at SRT >0.5 ng/ml. The relationship between HT duration and CR-free survival rate at 8yr was graphically explored according to the number of risk factors (0 vs 1 vs ≥2). RESULTS AND LIMITATIONS: Overall, 1125 men (89%) received SRT for rising PSA and 139 (11%) were treated for PSA persistence. Concomitant HT was administered to 363 patients (29%), with a median HT duration of 9mo. At median follow-up of 93mo after surgery, 182 patients developed CR. The 8-yr CR-free survival was 92%. On multivariable analysis, HT duration was inversely associated with the risk of CR (hazard ratio 0.95; p=0.022). A total of 531 (42%) patients had none of the prespecified risk factors, while 507 (40%) had one and 226 (18%) had two or more risk factors. The association between HT duration and CR was significantly different by risk factors (0 vs 1, p=0.001; 0 vs ≥2, p<0.0001). We observed a significant effect of HT duration for patients with two or more risk factors, for whom HT administration was beneficial when given for up to 36mo. This effect was attenuated among patients with one risk factor, with concomitant HT slightly beneficial when administered for a shorter time (<12mo). Conversely, for patients with no risk factors, the risk of CR remained low and constant regardless of HT duration. CONCLUSIONS: The oncologic benefit of HT duration among men receiving SRT for increasing PSA after RP depends on their clinical and pathologic characteristics. Our data suggested a significant effect of long-term HT for patients with two or more adverse features. Conversely, short-term HT was sufficient for patients with a single risk factor, whereas patients without any risk factors did not show a significant benefit from concomitant HT. PATIENT SUMMARY: We tested the impact of hormonal therapy (HT) duration during radiation therapy after radical prostatectomy. We identified three risk factors and observed a different impact of HT duration by clinical and pathologic characteristics. Patients with more adverse features benefit from long-term concomitant HT. On the contrary, for patients with a single risk factor, short-term HT may be reasonable. Patients without any risk factors did not show a significant benefit from concomitant HT.

Image-guided Stereotactic Body Radiotherapy in Metastatic Prostate Cancer.

BACKGROUND/AIM: In the last years, the use of Image Guided Stereotactic Radiotherapy (IG-SBRT) in patients with metastatic prostate cancer has increased. In this study, we aimed to assess the role of IG-SBRT in terms of local control and safety in patients with metastatic prostate cancer. MATERIALS AND METHODS: Primary and secondary endpoints of this prospective observational study were local control and safety related to IG-SBRT. All lesions were treated with 24 Gy as a single fraction or 27 Gy in 3 fractions. After SBRT, Systemic therapies were administered only after the occurrence of more than three synchronous active lesions in oligometastatic patients (patients with less than 4 active synchronous lesions) or new lesions occurrence in patients with more than 3 synchronous lesions. RESULTS: From April 2011 to June 2017, 78 metastatic lesions (32 bone and 46 node) from 51 patients with prostate cancer were treated. After a median follow-up of 18.5 months (range=3-103 months), only 2 lesions (4%) relapsed inside the radiation field. All local recurrences were located on the bone. Estimated 12 and 24 months local control ratios were 98.7 and 97.4%, respectively. Except for one case, toxicity greater than G2 was not recorded. CONCLUSION: IG-SBRT is safe and can be considered as a valid therapy in patients with metastatic prostate cancer requiring a long-lasting metastases control.

Stereotactic Body Radiotherapy in Patients with Lung Oligometastases from Colorectal Cancer.

AIM: To assess the role of stereotactic body radiotherapy (SBRT) in pulmonary metastases from colorectal cancer (CRC). PATIENTS AND METHODS: Thirty-three consecutive patients with pulmonary metastases from CRC who received SBRT were included in the analysis. The primary endpoints were local and systemic progression-free survival, a secondary endpoint was the safety profile of SBRT. RESULTS: A total of 56 lesions were treated with SBRT. A single nodule was treated in 15 patients, two in 13 and three in five. The radiotherapy dose and the adopted fractionations were 24-27 Gy as a single fraction for 40 lesions and 27-42 Gy in three fractions (2-3 times a week) for the other 16 lesions. After a median follow-up of 22.8 months (range=1.3-45.7 months), the median progression-free survival of the irradiated sites was 13.4 months. CONCLUSION: SBRT can be considered as local therapy in patients with lung metastases from CRC.

Detection of a second malignancy in prostate cancer patients by using [(18)F]Choline PET/CT: a case series.

BACKGROUND: The role of radiolabeled choline (Cho) in patients with biochemical recurrence after radical treatment for prostate cancer (PCa) is well established. Its widespread clinical use has prompted the depiction of incidentalomas, unusual sites of metastatic lesions, as well as false positive and negative cases. We reported a series of patients affected by biochemical recurrence of PCa imaged by [(18)F]Cho positron emission tomography/computed tomography (PET/CT) which resulted suspected for a second malignancy. CASE PRESENTATION: [(18)F]Cho PET/CT was performed in patients with biochemical PCa recurrence. From an internal clinical database we identified patients in which PET/CT resulted suspected for a second malignancy. A second malignancy was suspected in presence of "unusual" site of [(18)F]Cho uptake not consistent with clinical-instrumental history. Histology was used as reference standard for final diagnosis. Seven PCa patients (76 years, 71-84 years) with the suspicion of a second tumor based on [(18)F]Cho PET/CT findings were identified. Mean value of PSA at the time of [(18)F]Cho PET/CT was 2,37 ng/mL. The median time between PCa diagnosis and PET/CT was 6 years (range 0-14 years). In two cases history of a second malignancy (lung cancer and cutaneous basocellular carcinoma) was known (diagnosed 12 and 6 years after PCa, respectively). PET/CT identified 13 sites of [(18)F]Cho uptake (lung = 5, lymph node = 7, bone = 1). Final diagnosis was consistent with lung cancer in 5/7 cases (first diagnosis = 4/5, recurrence = 1/5), colorectal cancer and nodal metastases from melanoma in 1 case each. CONCLUSIONS: Although the clinical usefulness of Cho PET/CT for detecting cancer lesions other than prostate origin is known, for those patients who undergo this examination according to indication, the diagnosis of a second tumor has a significant impact on their therapeutic management.

Long-Term PSA Control with Repeated Stereotactic Body Radiotherapy in a Patient with Oligometastatic Castration-Resistant Prostate Cancer.

Prostate cancer (PCa) is one of the most common malignancies and main causes of cancer death in Western countries. In the presence of metastatic disease, systemic treatment remains the main clinical option. However, since the introduction of highly sensitive imaging techniques, a new clinical 'entity' of metastatic patients with a limited number of lesions has been defined: oligometastatic patients. In this patient group, the use of stereotactic body radiotherapy (SBRT) or other local therapies against all active sites of disease revealed by 18F-choline positron emission tomography/computed tomography (PET/CT) could achieve sufficient prostate-specific antigen (PSA) control. However, a clear benefit of this procedure in terms of significant endpoints is yet to be demonstrated. This case report describes our experience with treating a castration-resistant PCa patient with 18F-choline PET/CT-guided SBRT. Because of the occurrence of 5 metachronous lesions over 4 years, the pattern of recurrence was defined by the local multidisciplinary team as oligometastatic disease, and the patient was treated with 5 courses of SBRT which yielded good PSA control. He started systemic therapy with abiraterone acetate almost 5 years after the diagnosis of recurrent PCa.

Concomitant External-beam Irradiation and Chemotherapy Followed by High-dose Rate Brachytherapy Boost in the Treatment of Squamous Cell Carcinoma of the Vagina: A Single-Center Retrospective Study.

AIM: To assess the outcome of 35 patients with vaginal carcinoma treated with different radiotherapy modalities. MATERIALS AND METHODS: Thirty-one patients received external-beam irradiation (EBRT) to the entire vagina, para-vaginal area and pelvic nodes (total dose=45-50.4 Gy). Concomitant chemotherapy was used in 22 patients. Nineteen patients received additional 15-25 Gy high-dose-rate brachytherapy (BT) boost and eight received additional EBRT boost to the primary tumor site. Four women received exclusive 30-40 Gy high-dose-rate BT. RESULTS: Median progression-free survival and median overall survival were 22 months and 89 months, respectively. Age <70 years, use of EBRT plus BT, and concomitant chemotherapy were associated with better progression-free (p=0.002, p=0.007, and p=0.02) and overall (p=0.01, p=0.009, p=0.009) survival. CONCLUSION: Concomitant EBRT and chemotherapy followed by BT is the best treatment for vaginal carcinoma.

[(18)F]Choline PET/CT and stereotactic body radiotherapy on treatment decision making of oligometastatic prostate cancer patients: preliminary results.

BACKGROUND: A new entity of patients with recurrent prostate cancer limited to a small number of active metastatic lesions is having growing interest: the oligometastatic patients. Patients with oligometastatic disease could eventually be managed by treating all the active lesions with local therapy, i.e. either surgery or ablative stereotactic body radiotherapy. This study aims to assess the impact of [(18)F]Choline ([(18)F]FMCH) PET/CT and the use stereotactic body radiotherapy (SBRT) in patients (pts) with oligometastatic prostate cancer (PCa). METHODS: Twenty-nine pts with oligometastatic PCa (≤3 synchronous active lesions detected with [(18)F]FMCHPET/CT) were treated with repeated salvage SBRT until disease progression (development of > three active synchronous metastases). Primary endpoint was systemic therapy-free survival measured from the baseline [(18)F]FMCHPET/CT. RESULTS: A total of 45 lesions were treated with SBRT. After a median follow-up of 11.5 months (range 3-40 months), 20 pts were still in the study and did not receive any systemic therapy. Nine pts started systemic therapy, and the median time of the primary endpoint was 39.7 months (CI 12.20-62.14 months). No grade 3 or 4 toxicity was recorded. CONCLUSIONS: Repeated salvage [(18)F]FMCHPET/CT-guided SBRT is well tolerated and could defer the beginning of systemic therapy in selected patients with oligometastatic PCa.