Stereotactic radiotherapy for managing ovarian cancer oligoprogression under poly (ADP-ribose) polymerase inhibitors (PARPi).

OBJECTIVE: Poly (ADP-ribose) polymerase inhibitors (PARPi) have become a new standard of care for the maintenance treatment of advanced epithelial ovarian cancer. This study aims to evaluate the efficacy and safety of combining stereotactic body radiotherapy with PARPi continuation as a strategy to treat ovarian cancer oligoprogression on PARPi. METHODS: This is a multicenter retrospective study including ovarian cancer patients treated with stereotactic body radiotherapy and PARPi continuation for oligoprogression under PARPi maintenance therapy between June 2012 and May 2023 in three Italian centers. PARPi treatment was continued until further disease progression or unacceptable toxicity. The primary endpoint was the next-line systemic therapy-free interval. The Kaplan-Meier method was used to assess local control, progression-free survival, and overall survival. Univariate and multivariate Cox regression analyses were performed to evaluate potential clinical outcomes predictors. RESULTS: 46 patients were included, with a total of 89 lesions treated over 63 radiotherapy treatments. Lymph nodes were the most frequently treated lesions (80, 89.9%), followed by visceral lesions (8, 9%) and one case with a bone lesion (1.1%). Median follow-up was 25.9 months (range 2.8-122). The median next-line systemic therapy-free interval was 12.4 months (95% CI 8.3 to 19.5). A number of prior chemotherapy lines greater than five was significantly associated with a reduced next-line systemic therapy-free interval (HR 3.21, 95% CI 1.11 to 9.32, p=0.032). At the time of analysis, 32 (69.6%) patients started a new systemic therapy regimen, while 14 (30.4%) remained on the PARPi regimen. The 2-year progression-free survival, local failure-free survival, and overall survival rates were 10.7%, 78.1%, and 76.5%, respectively. Four patients (8.7%) experienced acute toxicity with G1 gastrointestinal events. CONCLUSION: Stereotactic body radiotherapy combined with PARPi continuation may be an effective and safe strategy for managing ovarian cancer patients with oligoprogression on PARPi maintenance therapy. Prospective research is warranted to shed more light on this approach.

Metastases-directed stereotactic body radiotherapy in combination with targeted therapy or immunotherapy: systematic review and consensus recommendations by the EORTC-ESTRO OligoCare consortium.

Stereotactic body radiotherapy (SBRT) for patients with metastatic cancer, especially when characterised by a low tumour burden (ie, oligometastatic disease), receiving targeted therapy or immunotherapy has become a frequently practised and guideline-supported treatment strategy. Despite the increasing use in routine clinical practice, there is little information on the safety of combining SBRT with modern targeted therapy or immunotherapy and a paucity of high-level evidence to guide clinical management. A systematic literature review was performed to identify the toxicity profiles of combined metastases-directed SBRT and targeted therapy or immunotherapy. These results served as the basis for an international Delphi consensus process among 28 interdisciplinary experts who are members of the European Society for Radiotherapy and Oncology (ESTRO) and European Organisation for Research and Treatment of Cancer (EORTC) OligoCare consortium. Consensus was sought about risk mitigation strategies of metastases-directed SBRT combined with targeted therapy or immunotherapy; a potential need for and length of interruption to targeted therapy or immunotherapy around SBRT delivery; and potential adaptations of radiation dose and fractionation. Results of this systematic review and consensus process compile the best available evidence for safe combination of metastases-directed SBRT and targeted therapy or immunotherapy for patients with metastatic or oligometastatic cancer and aim to guide today's clinical practice and the design of future clinical trials.

STereotactic Arrhythmia Radioablation (STAR): the Standardized Treatment and Outcome Platform for Stereotactic Therapy Of Re-entrant tachycardia by a Multidisciplinary consortium (STOPSTORM.eu) and review of current patterns of STAR practice in Europe.

The EU Horizon 2020 Framework-funded Standardized Treatment and Outcome Platform for Stereotactic Therapy Of Re-entrant tachycardia by a Multidisciplinary (STOPSTORM) consortium has been established as a large research network for investigating STereotactic Arrhythmia Radioablation (STAR) for ventricular tachycardia (VT). The aim is to provide a pooled treatment database to evaluate patterns of practice and outcomes of STAR and finally to harmonize STAR within Europe. The consortium comprises 31 clinical and research institutions. The project is divided into nine work packages (WPs): (i) observational cohort; (ii) standardization and harmonization of target delineation; (iii) harmonized prospective cohort; (iv) quality assurance (QA); (v) analysis and evaluation; (vi, ix) ethics and regulations; and (vii, viii) project coordination and dissemination. To provide a review of current clinical STAR practice in Europe, a comprehensive questionnaire was performed at project start. The STOPSTORM Institutions' experience in VT catheter ablation (83% ≥ 20 ann.) and stereotactic body radiotherapy (59% > 200 ann.) was adequate, and 84 STAR treatments were performed until project launch, while 8/22 centres already recruited VT patients in national clinical trials. The majority currently base their target definition on mapping during VT (96%) and/or pace mapping (75%), reduced voltage areas (63%), or late ventricular potentials (75%) during sinus rhythm. The majority currently apply a single-fraction dose of 25 Gy while planning techniques and dose prescription methods vary greatly. The current clinical STAR practice in the STOPSTORM consortium highlights potential areas of optimization and harmonization for substrate mapping, target delineation, motion management, dosimetry, and QA, which will be addressed in the various WPs.

Linac-based versus MR-guided SBRT for localized prostate cancer: a comparative evaluation of acute tolerability.

AIM: This study aims to compare acute toxicity of prostate cancer (PCa) stereotactic body radiotherapy (SBRT) delivered by MR-guided radiotherapy (MRgRT) with 1.5-T MR-linac or by volumetric modulated arc (VMAT) with conventional linac. METHODS: Patients with low-to-favorable intermediate risk class PCa were treated with exclusive SBRT (35 Gy in five fractions). Patients treated with MRgRT were enrolled in an Ethical Committee (EC) approved trial (Prot. n° 23,748), while patients treated with conventional linac were enrolled in an EC approved phase II trial (n° SBRT PROG112CESC). The primary end-point was the acute toxicity. Patients were included in the analysis if they had at least 6 months of follow-up for the primary end-point evaluation. Toxicity assessment was performed according to CTCAE v5.0 scale. International Prostatic Symptoms Score (IPSS) was also performed. RESULTS: A total of 135 patients were included in the analysis. Seventy-two (53.3%) were treated with MR-linac and 63 (46.7%) with conventional linac. The median initial PSA before RT was 6.1 ng/ml (range 0.49-19). Globally, acute G1, G2, and G3 toxicity occurred in 39 (28.8%), 20 (14.5%), and 5 (3.7%) patients. At the univariate analysis, acute G1 toxicity did not differ between MR-linac and conventional linac (26.4% versus 31.8%), as well as G2 toxicity (12.5% versus 17.5%; p = 0.52). Acute G2 gastrointestinal (GI) toxicity occurred in 7% and 12.5% of cases in MR-linac and conventional linac group, respectively (p = 0.06), while acute G2 genitourinary toxicity occurred in 11% and 12.8% in MR-linac and conventional linac, respectively (p = 0.82). The median IPSS before and after SBRT was 3 (1-16) and 5 (1-18). Acute G3 toxicity occurred in two cases in the MR-linac and three cases in the conventional linac group (p = n.s.). CONCLUSION: Prostate SBRT with 1.5-T MR-linac is feasible and safe. Compared to conventional linac, MRgRT might to potentially reduce the overall G1 acute toxicity at 6 months, and seems to show a trend toward a lower incidence of grade 2 GI toxicity. A longer follow-up is necessary to assess the late efficacy and toxicity.

Stereotactic body radiotherapy for pulmonary oligometastases: a monoinstitutional analysis of clinical outcomes and potential prognostic factors.

PURPOSE: We report the retrospective data of a cohort of patients who received stereotactic body radiotherapy for pulmonary oligometastases, aiming to assess the clinical factors potentially affecting clinical outcomes. METHODS: The present series reports the outcomes of a cohort of 71 patients with pulmonary oligometastases with no extrapulmonary disease. All patients were treated with stereotactic body radiotherapy (SBRT) performed with volumetric modulated arc therapy-image guided radiotherapy (VMAT-IGRT) to up to five secondary lesions. Survival estimates were performed using the Kaplan-Meier method. RESULTS: A total of 98 lesions in 71 patients were treated from February 2014 to August 2020. The most frequent histologies were colorectal in 37.7%, lung cancer in 44.8%, head and neck cancer in 8.1%, and other in 9.4%. Median age was 71 years (range 32-93 years). Concurrent systemic therapy was administered in 32.3%. SBRT was delivered to a median total dose of 60 Gy (range 55-70 Gy) in 3-10 fractions for a median BED10 = 105 Gy (range 96-180 Gy). Median follow-up was 29.5 months (range 6-81), with no acute or late G > 2 adverse event. Our LC rates at 2 and 4 years were 92.4 and 89.8%, respectively. DPFS rates at 2 and 4 years were 45.3 and 27.2%, respectively. A second SBRT course was proposed in 21 patients (29.5%) who developed an oligoprogression, resulting in median time to second progression of 9 months (range 2-44) and 2­year PFS2 rate of 42.4%. At univariate analysis, patients with sequential oligometastases reported better OS rates (p = 0.002), which was also confirmed at multivariate analysis, where distant progression was also related to worse OS (p = 0.022). Higher local control rates relate to better PFS (p = 0.04). The 2­ and 4­year OS rates were 61 and 39.7% CONCLUSION: SBRT is feasible for pulmonary oligometastases with favorable outcomes and toxicity. At multivariate analysis, patients with sequential oligometastatic progression maintain a survival advantage. Also, local control was found to be related to improved PFS rates.

Stereotactic ablative radiotherapy in patients with refractory ventricular tachyarrhythmia.

Stereotactic ablative body radiotherapy (SABR) is an innovative therapeutic approach in patients (pts) with a diagnosis of refractory ventricular tachyarrhythmia (VT) after the use of drugs, radiofrequency catheter ablation, and/or defibrillator (ICD) implant. The current efficacy data of SABR are limited and several prospective clinical studies are ongoing to support the use of ablative radiation dose to control VT. The aim of the current prospective pilot study is to report the efficacy and tolerability of SABR in ICD implanted pts with refractory VT in our centre. Non-invasive electroanatomical mapping (EAM), cardiac computed tomography (CT), and 18F-fluorodeoxyglucose positron emission (FDG-PET)-CT scan were used and combined with a radiation CT scan. A dose prescription of 25 Gy in a single dose was delivered by volumetric modulated arc therapy (VMAT) Linac-based. The primary endpoint was efficacy, defined as a reduction in ICD shocks after SABR treatment, while the secondary endpoint was safety. Six consecutive pts (five males and one female) implanted with an ICD and with three or more VT were enrolled. One pts died after 1 month, due to end-stage heart failure. Two pts experienced ICD shocks in VT 2 and 5 months after treatment. Three pts experienced no more ICD shocks on VT after therapy. Our data suggest the efficacy and safety of SABR treatment in pts with VT. Larger dataset of pts and longer follow-up are otherwise required to validate the impact of SABR as a standardized treatment in these pts.

Postoperative moderately hypofractionated radiotherapy in prostate cancer: a mono-institutional propensity-score-matching analysis between adjuvant and early-salvage radiotherapy.

AIM: To evaluate the impact of moderately hypofractionated postoperative radiotherapy (RT) in prostate cancer (PCa). MATERIALS AND METHODS: The data of 304 surgically resected PCa patients were analyzed. One hundred and five patients underwent adjuvant RT (aRT), 77 early-savage RT (esRT), and 123 salvage RT (sRT). Biochemical relapse-free survival (BRFS), progression-free survival (PFS) and toxicity were analyzed. A propensity score matching (PSM) was performed to account for potential confounders between aRT and esRT groups. RESULTS: The median follow-up was 33 months. Three-year BRFS and PFS were 82 and 85.2%, respectively, in the overall population. At the multivariate analysis, Gleason score and hormone therapy were factors independently correlated with BRFS and PFS. After PSM, there was no difference in BRFS and PFS between aRT and esRT patients. Severe toxicity was represented by grade 3 urinary incontinence (3.5%) and urgency (1%), and aRT correlated with increased any-grade acute toxicity. Severe grade 3 gastrointestinal late toxicity occurred in 1.3% of cases. CONCLUSION: Postoperative moderately hypofractionated RT achieved acceptable disease control rate and demonstrated no increased or unexpected toxicity. Future prospective studies should evaluate the role of postoperative RT in patients with unfavorable disease characteristics.

Radiomic analysis to predict local response in locally advanced pancreatic cancer treated with stereotactic body radiation therapy.

PURPOSE: Aim of this study is to assess the ability of contrast-enhanced CT image-based radiomic analysis to predict local response (LR) in a retrospective cohort of patients affected by pancreatic cancer and treated with stereotactic body radiation therapy (SBRT). Secondary aim is to evaluate progression free survival (PFS) and overall survival (OS) at long-term follow-up. METHODS: Contrast-enhanced-CT images of 37 patients who underwent SBRT were analyzed. Two clinical variables (BED, CTV volume), 27 radiomic features were included. LR was used as the outcome variable to build the predictive model. The Kaplan-Meier method was used to evaluate PFS and OS. RESULTS: Three variables were statistically correlated with the LR in the univariate analysis: Intensity Histogram (StdValue feature), Gray Level Cooccurrence Matrix (GLCM25_Correlation feature) and Neighbor Intensity Difference (NID25_Busyness feature). Multivariate model showed GLCM25_Correlation (P = 0.007) and NID25_Busyness (P = 0.03) as 2 independent predictive variables for LR. The odds ratio values of GLCM25_Correlation and NID25_Busyness were 0.07 (95%CI 0.01-0.49) and 8.10 (95%CI 1.20-54.40), respectively. The area under the curve for the multivariate logistic regressive model was 0.851 (95%CI 0.724-0.978). At a median follow-up of 30 months, median PFS was 7 months (95%CI 6-NA); median OS was 11 months (95%CI 10-22 months). CONCLUSIONS: This analysis identified a radiomic signature that correlates with LR. To confirm these results, prospective studies could identify patient sub-groups with different rates of radiation dose-response to define a more personalized SBRT approach.

The role of radiotherapy in patients with solid tumours after solid organ transplantation: a systematic review.

For patients diagnosed with cancer who have previously received an organ transplant, radiotherapy represents a challenging clinical scenario without well established care algorithms. Immunosuppressive therapy can be a cause for concern among clinicians treating this category of patients. Potential immune modulation following irradiation could affect recipient organ tolerance and the outcomes of the transplantation itself. The main aim of this systematic review was to define the safety and effectiveness of radiotherapy in patients diagnosed with cancer who have previously received an organ transplant. We searched PubMed and Embase for articles published between Jan 1, 1995, and April 30, 2020 for studies in patients who had undergone radiotherapy for post-transplantation malignancies. The Review is framed by the PICO (population, intervention, control, and outcomes) criteria, and primarily focuses on modern treatment techniques.

Daily dosimetric variation between image-guided volumetric modulated arc radiotherapy and MR-guided daily adaptive radiotherapy for prostate cancer stereotactic body radiotherapy.

AIM: To evaluate differences between MR-guided daily-adaptive RT (MRgRT) and image-guided RT (IGRT) with or without fiducial markers in prostate cancer (PCa) stereotactic body radiotherapy (SBRT) in terms of dose distribution on critical structures. MATERIAL AND METHODS: Two hundred treatment sessions in 40 patients affected by low and intermediate PCa were evaluated. The prescribed dose was 35 Gy in 5 fractions delivered on alternate days. MRgRT patients (10) were daily recontoured, re-planned, and treated with IMRT technique. IGRT patients without (20) and with (10) fiducials were matched on soft tissues or fiducials and treated with VMAT technique. Respective CBCTs were retrospectively delineated and the prescribed plan was overlaid for dosimetric analysis. The daily dose for rectum, bladder, and prostate was registered. RESULTS: MRgRT resulted in a significantly lower rate of constraints violation as compared to IGRT without fiducials, especially for rectum V28Gy, rectum V32Gy, rectum V35Gy, rectum Dmax, and bladder Dmax. IGRT with fiducials reported high accuracy levels, comparable to MRgRT. MRgRT and IGRT with fiducials reported no significant prostate CTV underdosage, while IGRT without fiducials was associated with occasional cases of prostate CTV under dosage. CONCLUSION: MR-guided daily-adaptive SBRT seems a feasible and accurate strategy for treating prostate cancer with ablative doses. IGRT with the use of fiducials provides a comparable level of accuracy and acceptable real-dose distribution over treatment fractions. Future study will provide additional data regarding the tolerability and the clinical outcome of this new technological approach.

Salvage local treatment for localized radio-recurrent prostate cancer: a narrative review and future perspectives.

Although dose escalation protocols have improved biochemical control in prostate cancer radiotherapy, 10-45% of patients will experience disease recurrence. The prostate and seminal vesicles are the most frequent site of the first relapse. Traditionally, these patients have been managed with hormonal therapy, which is not curative. Recent improvements in diagnostic tests (e.g., multiparametric magnetic resonance and molecular imaging, including PET/CT scan with choline or Ga-PSMA) and new treatment techniques (e.g., stereotactic body radiation therapy or other minimally invasive alternatives like high-intensity focus ultrasound, cryoablation or high-dose-rate brachytherapy) offer new therapeutic strategies with the potential to cure some patients with limited adverse effects. In this narrative review, the authors present the most recent evidence to help identify the most suitable candidates for salvage treatment.

Sequencing radium 223 and other life-prolonging agents in castration-resistant prostate cancer patients.

Background: Radium 223 (RA223) is currently administered as part of a therapeutic sequence with the other life-prolonging agents (LPAs) for metastatic castration-resistant prostate cancer (mCRPC). Patients & methods: We retrospectively reviewed the clinical records of patients who had received at least three LPAs including RA223. Results: Median overall survival (OS) from the start of first-line treatment was 39.8 months, with the patients who completed all six planned courses of RA223 having a longer OS than those who did not (53.2 vs 29.5 months; p < 0.0001). Conclusions: Our study confirms the activity of RA223 regardless of the treatment line in which it is administered and suggests that patient selection plays a central role in maximizing this activity.

PROACTA: a survey on the actual attitude of the Italian radiation oncologists in the management and prescription of hormonal therapy in prostate cancer patients.

AIM: To investigate the actual attitude of Radiation Oncologists in the prescription of hormonal therapy in prostate cancer (PC) with or without Radiation Therapy (RT). MATERIALS AND METHODS: In 2019, a survey named Prescription of Radiation Oncologists ACtual Attitude including 18 items was sent to all Italian Radiation Oncologists of the Italian Association of Radiotherapy and Clinical Oncology. The first 4 items were about the Radiation Oncology Centers characteristics and years of practice of the respondents. The remaining 14 items concerned the setting in which hormone therapy was prescribed in PC patients (radical, postprostatectomy/oligometastatic state), the kind of drug, the choice modality (Multidisciplinary Group/autonomy decision) and other factors. RESULTS: A total of 127 questionnaires were returned, mainly by Northern Italy Radiation Oncology Centres (44.9%), and by experienced Radiation Oncologists (78%), who declared to prescribe independently hormone therapy in 85.8% of cases. The Androgen deprivation therapy (ADT) prescription in castration naive PC was made independently by 56.7% of respondents and associated with radical RT, postoperative or salvage RT according to various risk factors. In castration-sensitive oligorecurrent PC, the majority (51.2%) administered ADT only if local ablative treatment was not feasible, while in metastatic castration resistant disease novel hormone therapy use was established in almost half of cases within multidisciplinary board. Radiation Oncologists could prescribe these drugs independently in 64% of cases. CONCLUSION: Our survey established the prescription attitude of ADT and new hormonal agents (abiraterone, enzalutamide, apalutamide) by Italian Radiation Oncologists and highlighted the importance of expertise in global PC management.

Stereotactic Ablative radiation therapy (SABR) for cardiac arrhythmia: A new therapeutic option?

AIM: Stereotactic ablative radiation therapy (SABR) is used in non-oncologic indications, recently even for cardiac arrhythmias. Thus, aim of this analysis is to review preclinical, early clinical evidences and future direction of the latter new treatment approach. METHOD: A collection of available data regarding SABR and cardiac arrhythmias was made, by Pubmed research and 2 independent researchers, including preclinical and clinical data. A review of ongoing trials was conducted on ClinicalTrials.gov. RESULTS: Preclinical research conducted in animal models showed that a safe and effective noninvasive treatment approach for cardiac arrhythmias could be represented by SABR with a median time of response around 2-3 months. The treatment dose plays a crucial role: the atrioventricular node would seem more radiosensitive than the other cardiac electric zones. Clinical data, such as published case series, case reports and early prospective studies, have already suggested the feasibility, efficacy and safety of SABR (25 Gy in one session) for refractory ventricular arrhythmias. CONCLUSION: Considering the ongoing trials of SABR and new technological improvements in radiotherapy (e.g. hybrid magnetic resonance) and in arrhythmias noninvasive mapping systems, the future analyses will improve the reliability of those preliminary results.

Radiotherapy activities and technological equipment in Veneto, Italy: a report from the Rete Radioterapica Veneta.

BACKGROUND: Despite the pivotal role of radiotherapy in oncology, the provision of radiation treatments remains inadequate in many areas of the world. The present report is an assessment conducted among Radiation Oncology centers of Veneto region with the aim to collect information concerning radiotherapy assets and technological equipment availability. METHODS: Data concerning Veneto Radiation Oncology departments about radiotherapy activities, number of treatments, techniques used and radiotherapy machines available were collected. The reference time period was 2018. Reimbursement system databases and business intelligence systems were used. Extra-regional attraction and migration were evaluated. When available, data were compared to previous years. RESULTS: Veneto in 2018 was endowed with 1 megavolt unit for about 153,000 inhabitants. The number of megavolt machines per million inhabitants resulted to be 6.72. In 51% of radiotherapy treatments, intensity-modulated techniques were performed. Six percent of treatments were administered to extra-regional patients. CONCLUSION: Radiotherapy assets and equipment in Veneto seem to be appropriate to standard requests in terms of availability and technology.

Stereotactic body radiotherapy for oligometastatic castration sensitive prostate cancer using 1.5 T MRI-Linac: preliminary data on feasibility and acute patient-reported outcomes.

OBJECTIVES: To report preliminary data on feasibility and patient-reported outcomes following PSMA-PET/CT guided SBRT by means of 1.5 T MRI-Linac. METHODS AND MATERIALS: Between October 2019 and April 2020, twenty consecutive castration sensitive oligorecurrent prostate cancer patients were enrolled in an ethical committee approved prospective observational study (Protocol n. XXXX) and treated with PSMA-PET/CT guided SBRT by means of 1.5 T MRI-Linac (Unity, Elekta AB, Stockholm, Sweden). The mean delivered dose was 35 Gy in 5 fractions. Clinicians reported toxicity was prospectively collected according to Common Terminology Criteria for Adverse Events v5.0. Quality of life (QoL) assessment was performed using EORTC-QLQ C30 questionnaires administered at baseline, end of treatment and at first follow-up. RESULTS: Twenty-five lesions in 20 castration sensitive oligorecurrent patients were treated: the most commonly treated anatomic sites were nodal (n = 16) and pelvic bone (n = 9). Median PSA-value preMRI guided SBRT was 1.16 ng/mL (range, 0.27-8.9), whereas median PSA value at first follow-up after SBRT was 0.44 ng/mL (range, 0.06-8.15). At first follow-up, for 16 patients showing detectable PSA, PSMA-PET/CT was performed detecting, respectively, in 6 cases partial response and in 10 cases complete response. In the remaining cases, PSA-value was undetectable after SBRT. Radiotherapy treatment was safe and well tolerated according to the PROMs. No acute G2 or higher toxicities were recorded. CONCLUSIONS: The current series represent the largest one exploring the feasibility and patient-reported outcomes following PSMA-PET/CT guided SBRT by means of 1.5 T MRI-Linac. The preliminary findings here reported are encouraging in terms of effectiveness and tolerability.

Recurrence pattern of stereotactic body radiotherapy in oligometastatic prostate cancer: a multi-institutional analysis.

PURPOSE: For patients with oligometastatic/oligorecurrent/oligoprogressive lymph node metastases from PCa, metastases-directed therapy is an emerging strategy. The aim of this retrospective study was to evaluate the oncological outcome and pattern of recurrence in patients treated with stereotactic body radiation therapy (SBRT) to lymph node metastases. METHODS: In this multi-institutional analysis, patients with a maximum of five lymph node metastases from PCa treated with SBRT were included. Primary endpoints of the analysis were local control (LC), out-of-field nodal progression-free survival (NPFS), overall progression-free survival (PFS), and overall survival (OS). RESULTS: 109 patients and 155 lymph node metastases were evaluated. Patients' median age was 70.8 years (range 51-84) and median PSA before SBRT was 1.88 ng/ml (range 0.3-45.5 ng/ml). The dose delivered to the target ranged from 25 to 48 Gy in 4-7 fractions; median BED1.5 Gy was 198 Gy (range 108.3-432 Gy). With a median follow-up of 16 months, LC rates at 1 and 3 years were 93% and 86%, respectively. In-field progression of disease was observed in 11 (7%) lesions. One- and 3­year NPFS was 59% and 29%, and median NPFS was 15 months. Rates of OS at 1 and 3 years were 100% and 95%. The median time to administration of a systemic treatment after SBRT was 7.8 months (1.7-54.8). CONCLUSION: SBRT is an effective and well-tolerated treatment option in the management of lymph node metastases from PCa. Prospective trials are necessary to better select patients who benefit most from this ablative focal treatment and better define the recurrence patterns.

Disease course of lung oligometastatic colorectal cancer treated with stereotactic body radiotherapy.

PURPOSE: Stereotactic body radiotherapy (SBRT) or stereotactic ablative radiotherapy (SABR) has been shown to increase survival rates in oligometastatic disease (OMD), but local control of colorectal metastases remains poor. We aimed to explore the natural course of oligometastatic colorectal cancer and to investigate how SBRT of lung metastases can delay the progression to polymetastatic disease (PMD). METHODS: 107 lung oligometastases in 38 patients were treated with SBRT at a single institution. The median number of treated lesions was 2 (range 1-5). Time to PMD (ttPMD) was defined as the time from SBRT to the occurrence of >5 new metastases. Genetic biomarkers such as EGFR, KRAS, NRAS, BRAF, and microsatellite instability were investigated as predictive factors for response rates. RESULTS: Median follow-up was 28 months. At median follow-up, 7 patients were free from disease and 31 had progression: 18 patients had sequential oligometastatic disease (SOMD) and 13 polymetastatic progression. All SOMD cases received a second SBRT course. Median progression-free survival (PFS) was 7 months (range 4-9 months); median ttPMD was 25.8 months (range 12-39 months) with 1­ and 2­year PFS rates of 62.5% and 53.4%, respectively. 1­ and 2­year local PFS (LPFS) rates were 91.5% and 80%, respectively. At univariate analysis, BRAF wildtype correlated with better LPFS (p = 0.003), SOMD after primary SBRT was associated with longer cancer-specific survival (p = 0.031). Median overall survival (OS) was 39.5 months (range 26-64 months) and 2­year OS was 71.1%. CONCLUSION: The present results support local ablative treatment of lung metastases using SBRT in oligometastatic colorectal cancer patients, as it can delay the transition to PMD. Patients who progressed as SOMD maintained a survival advantage compared to those who developed PMD.

Linac-based SBRT as a feasible salvage option for local recurrences in previously irradiated prostate cancer.

BACKGROUND AND OBJECTIVE: The optimal management of prostate cancer (PC) recurrences after definitive or postoperative radiotherapy (RT) is still controversial. The aim of the present retrospective study was to report the preliminary clinical results and toxicity of a mono-institutional series of patients re-irradiated with linac-based SBRT in recurrent prostate cancer. METHODS: Inclusion criteria were previous definitive or adjuvant/salvage RT, evidence of biochemical recurrence and radiological detection of local relapse (Magnetic Resonance Imaging or PSMA/choline-Positron Emission Tomography), and IPSS <10. Toxicity was assessed according to Common Terminology Criteria for Adverse Events v4.0. RESULTS: Between 12/2014 and 12/2019, 24 patients with median age 75 years (65-89) underwent re-RT for PC recurrence. Median follow-up was 21 months (2-68). The recurrences occurred in 13 cases within the prostate and in 11 cases within the prostate bed. All patients were treated with SBRT to a median total dose of 30 Gy (25-36 Gy) in 5-6 fractions, and simultaneous androgen deprivation therapy was administered in 4 patients. Acute toxicity was G1 in 8.3% and G2 in 12.5% for genitourinary (GU), no acute gastrointestinal (GI) toxicity occurred. Concerning late side effects, 19.7% of patients were found to have ≥G2 GU toxicity, including one G3 urethral stenosis. Only one case of G1 late GI toxicity occurred and no ≥G2. The 2­year overall survival was 95%. The 1­ and 2­year biochemical relapse-free survival (BRFS) and progression-free survival (PFS) rates were 80 and 54.9%, respectively. CONCLUSION: Despite of the heterogeneity of the sample, linac-based SBRT as a salvage treatment in previously irradiated locally recurrent PC patients seems to be a safe and feasible treatment option. Long-term data are pending.

Correction to: Standard (8 weeks) vs long (12 weeks) timing to minimally-invasive surgery after NeoAdjuvant Chemoradiotherapy for rectal cancer: a multicenter randomized controlled parallel group trial (TiMiSNAR).

Following publication of the original article [1], the authors reported that the family name of the author, Ludovica Baldari, was misspelled.