Stereotactic Body Radiation Therapy and Abiraterone Acetate for Patients Affected by Oligometastatic Castrate-Resistant Prostate Cancer: A Randomized Phase II Trial (ARTO)

PURPOSE

ARTO (ClinicalTrials.gov identifier: NCT03449719) is a multicenter, phase II randomized clinical trial testing the benefit of adding stereotactic body radiation therapy (SBRT) to abiraterone acetate and prednisone (AAP) in patients with oligometastatic castrate-resistant prostate cancer (CRPC).

MATERIALS AND METHODS

All patients were affected by oligometastatic CRPC as defined as three or less nonvisceral metastatic lesions. Patients were randomly assigned 1:1 to receive either AAP alone (control arm) or AAP with concomitant SBRT to all the sites of disease (experimental arm). Primary end point was the rate of biochemical response (BR), defined as a prostate-specific antigen (PSA) decrease ≥50% from baseline measured at 6 months from treatment start. Complete BR (CBR), defined as PSA < 0.2 ng/mL at 6 months from treatment, and progression-free survival (PFS) were secondary end points.

RESULTS

One hundred and fifty-seven patients were enrolled between January 2019 and September 2022. BR was detected in 79.6% of patients (92% v 68.3% in the experimental v control arm, respectively), with an odds ratio (OR) of 5.34 (95% CI, 2.05 to 13.88; P = .001) in favor of the experimental arm. CBR was detected in 38.8% of patients (56% v 23.2% in the experimental v control arm, respectively), with an OR of 4.22 (95% CI, 2.12 to 8.38; P < .001). SBRT yielded a significant PFS improvement, with a hazard ratio for progression of 0.35 (95% CI, 0.21 to 0.57; P < .001) in the experimental versus control arm.

CONCLUSION

The trial reached its primary end point of biochemical control and PFS, suggesting a clinical advantage for SBRT in addition to first-line AAP treatment in patients with metastatic castration-resistant prostate cancer.

Magnetic resonance guided SBRT reirradiation in locally recurrent prostate cancer: a multicentric retrospective analysis

AIMS

Reirradiation of prostate cancer (PC) local recurrences represents an emerging challenge for current radiotherapy. In this context, stereotactic body radiation therapy (SBRT) allows the delivery of high doses, with curative intent. Magnetic Resonance guided Radiation Therapy (MRgRT) has shown promising results in terms of safety, feasibility and efficacy of delivering SBRT thanks to the enhanced soft tissue contrast and the online adaptive workflow. This multicentric retrospective analysis evaluates the feasibility and efficacy of PC reirradiation, using a 0.35 T hybrid MR delivery unit.

METHODS

Patients affected by local recurrences of PC and treated in five institutions between 2019 and 2022 were retrospectively collected. All patients had undergone previous Radiation Therapy (RT) in definitive or adjuvant setting. Re-treatment MRgSBRT was delivered with a total dose ranging from 25 to 40 Gy in 5 fractions. Toxicity according to CTCAE v 5.0 and treatment response were assessed at the end of the treatment and at follow-up.

RESULTS

Eighteen patients were included in this analysis. All patients had previously undergone external beam radiation therapy (EBRT) up to a total dose of 59.36 to 80 Gy. Median cumulative biologically effective dose (BED) of SBRT re-treatment was 213,3 Gy (103,1-560), considering an α/β of 1.5. Complete response was achieved in 4 patients (22.2%). No grade ≥ 2 acute genitourinary (GU) toxicity events were recorded, while gastrointestinal (GI) acute toxicity events occurred in 4 patients (22.2%).

CONCLUSION

The low rates of acute toxicity of this experience encourages considering MRgSBRT a feasibile therapeutic approach for the treatment of clinically relapsed PC. Accurate gating of target volumes, the online adaptive planning workflow and the high definition of MRI treatment images allow delivering high doses to the PTV while efficiently sparing organs at risk (OARs).

Multiparametric imaging guided HDR interventional radiotherapy (brachytherapy) boost in localized prostate cancer: a multidisciplinary experience

OBJECTIVE

The aim of this study was to report a monoinstitutional multidisciplinary experience about the use of multiparametric imaging to identify the areas with higher risk of relapse in localized prostate cancer, with the purpose of allowing a biologically planned target dose escalation.

PATIENTS AND METHODS

We performed a retrospective evaluation of patients diagnosed with prostate cancer who received treatments at our Interventional Oncology Center with interstitial interventional radiotherapy from 2014 to 2022. Inclusion criteria were histologically confirmed localized prostate cancer; and National Comprehensive Cancer Network (NCCN) risk class unfavorable intermediate or high/very high risk. The diagnostic work-up included multiparametric Magnetic resonance imaging (MRI), multiparametric Transrectal ultrasound (TRUS), Positron Emission Tomography Computed Tomography (PET-CT) with choline or PSMA (or alternatively bone scan). All patients were assessed and received one treatment with interstitial high-dose-rate interventional radiotherapy (brachytherapy) delivering external beam radiotherapy (46 Gy). All procedures were performed using transrectal ultrasound guidance under general anesthesia and the prescribed doses were 10 Gy to the whole prostate, 12 Gy to the peripheral zone and 15 Gy to the areas at risk.

RESULTS

We report the data of 21 patients who were considered for the statistical analysis with a mean age of 62.5 years. The mean PSA nadir was 0.03 ng/ml (range 0-0.09). So far, no biochemical nor radiological recurrences have been recorded in our series. Regarding acute toxicity, the most commonly reported side effects were G1 urinary in 28.5% of patients and G2 urinary in 9.5%; all recorded acute toxicities resolved spontaneously.

CONCLUSIONS

We present a real-life experience of biologically planned local dose escalation by interventional radiotherapy (brachytherapy) boost, followed by external beam radiotherapy in patients with intermediate unfavorable- or high/very high risk. The local control and the biochemical control rates are proved to be excellent and the toxicity profile tolerable.

ARTO trial-(NCT03449719): Early results from a phase II randomized trial testing stereotactic body radiation therapy in patients with oligometastatic castration-resistant prostate cancer undergoing I line treatment with abiraterone acetate

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Background: ARTO (NCT03449719) is a multicentre, randomized trial started in January 2019 and currently running in 16 Italian centres, testing the benefit of adding stereotactic body radiation therapy (SBRT) to Abiraterone Acetate (AA) in oligometastatic Castrate Resistant Prostate Cancer (CRPC) patients. Seventy-nine per cent of the target accrual population has been currently enrolled. Here we present a report about early efficacy results of SBRT+AA combination. Methods: Data from patients with ≥ 6 months of follow up were reported. All patients were affected by oligometastatic CRPC, defined as ≤ 3 non-visceral metastatic lesions. Patients were randomized 1:1 to receive either AA alone (control arm) or associated with concomitant SBRT on all sites of disease (treatment arm). Primary endpoint of the trial is rate of biochemical response (BR, defined as a PSA decrease ≥ 50% from baseline measured within 6 months from treatment start). Complete biochemical response (CBR, defined as PSA at 6 months ≤ 0.2 ng/ml) is a secondary endpoint of the trial. Results: Overall, 123 patients have been currently enrolled in ARTO trial. To date, 98 patients had ≥ 6 months of follow-up and were evaluable for the present analysis. BR was detected in 75 (76.5%) patients (82.2% vs. 71.7% in treatment vs. control arm, respectively), with an unadjusted odds ratio (OR) equal to 1.83 (95% CI 0.69-4.82, p-value 0.22). After adjustment for baseline PSA and the number of metastatic sites ( > 1 vs. 1), the OR for BR was 2.23 (95% CI 0.74-6.73, p-value 0.15). CBR was detected in 36 (36.7%) patients (46.7% vs. 28.3% in treatment vs. control arm, respectively), with an unadjusted OR of 2.22 (95% CI 0.96-5.12, p-value 0.06), and an adjusted OR of 2.31 (95% CI 0.90-5.92, p-value 0.08). In multivariable models, baseline PSA and the number of metastatic sites > 1 were non-statistically associated with CBR, with OR equal to 0.92 (95% CI 0.85-1.01, p-value 0.06) and 1.20 (95% CI 0.46-3.09, p-value 0.71), respectively. Conclusions: Results showed promising efficacy of SBRT+AA combination if compared to systemic treatment alone for oligometastatic CRPC, OR for BR and CBR were doubled in treatment vs. control arm, even if statistical significance is not yet reached. Interestingly, baseline burden of disease seems to predict increased outcome after SBRT, suggesting that selection criteria for local treatment may be further refined. Complete results for primary endpoint are awaited in 2022, after enrollment and follow-up completion of whole cohort, and may confirm these early outcomes in a larger population. Clinical trial information: NCT03449719.

Radiation therapy for prostate cancer: What's the best in 2021

Radiotherapy is highly involved in the management of prostate cancer. Its features and potential applications experienced a radical evolution over last decades, as they are associated to the continuous evolution of available technology and current oncological innovations. Some application of radiotherapy like brachytherapy have been recently enriched by innovative features and multidisciplinary dedications. In this report we aim to put some questions regarding the following issues regarding multiple aspects of modern application of radiation oncology: the current application of radiation oncology; the modern role of stereotactic body radiotherapy (SBRT) for both the management of primary lesions and for lymph-nodal recurrence; the management of the oligometastatic presentations; the role of brachytherapy; the aid played by the application of the organ at risk spacer (spacer OAR), fiducial markers, electromagnetic tracking systems and on-line Magnetic Resonance guided radiotherapy (MRgRT), and the role of the new opportunity represented by radiomic analysis.

Bone Marrow Activation After Chemotherapy Presenting as Diffuse Skeletal Uptake on 18F-Fluorocholine PET/CT

ABSTRACT

Diffuse 18F-FDG skeletal uptake due to chemotherapy-induced bone marrow activation is well documented, whereas it has never been reported with 18F-fluorocholine. We described a patient with pelvic recurrence of prostate cancer at 18F-fluorocholine PET/CT. A second PET/CT after docetaxel showed minimal residual activity in pelvis, but it revealed diffuse, intense 18F-fluorocholine skeletal uptake. Considering biochemical and metabolic response and absence of morphologically suspected bone lesions, skeletal hyperactivity was interpreted as chemotherapy-related bone marrow rebound rather than diffuse metastatic involvement, as confirmed by its resolution after treatment ended. The occurrence of such 18F-fluorocholine pattern should be considered to avoid imaging misinterpretation.

Simultaneous Integrated Radiotherapy Boost to the Dominant Intraprostatic Lesion: Final Results of a Phase I/II Trial

BACKGROUND/AIM

Late toxicity and long-term outcomes of a phase I-II trial on patients with prostate cancer treated with an integrated boost to the dominant intraprostatic lesion (DIL) are reported.

PATIENTS AND METHODS

Patients were treated using intensity-modulated radiotherapy, with a simultaneous integrated boost to the DIL, defined on staging magnetic resonance imaging, delivering 72 Gy in 1.8 Gy/fraction to prostate/seminal vesicles and 80 Gy in 2 Gy/fraction to the DIL. The primary endpoint was acute toxicity and secondary endpoints were late toxicity and biochemical disease-free survival.

RESULTS

Forty-four patients were enrolled. The median follow-up was 120 (range=25-150) months. Five-year rates of grade 3 late gastrointestinal and genitourinary toxicity were 2.3% and 4.5%, respectively; only one grade 4 late genitourinary toxicity was recorded. Five-year biochemical relapse-free and overall survival rates were 95.3% and 95.5%, respectively.

CONCLUSION

The treatment was well tolerated and achieved excellent results in terms of outcome in patients with low-intermediate Gleason's score and low risk of nodal metastasis.

Radiotherapy of Prostate Carcinoma: A Comparison of the Predictive Role of EAU Versus NCCN Risk Stratification Systems

BACKGROUND/AIM

To compare the predictive efficacy of National Comprehensive Cancer Network (NCCN) and European Association of Urology (EAU) risk stratification systems in radiotherapy of prostate cancer.

PATIENTS AND METHODS

One-thousand-nine-hundred-nine patients treated with definitive (1,074), adjuvant (381), and salvage radiotherapy (454) were analysed.

RESULTS

Both systems significantly predicted biochemical-relapse-free-survival, metastasis-free-survival, and disease-free-survival, while only the NCCN system correlated with local-control in the definitive radiotherapy group. In the adjuvant setting, both systems failed to predict all outcomes. In the salvage setting, only the NCCN system significantly predicted biochemical-relapse-free-survival, metastasis-free-survival and disease-free-survival.

CONCLUSION

This analysis confirms the efficacy of both systems in definitive radiotherapy and suggests the utility of the NCCN also in salvage radiotherapy.

BIT-ART: Multicentric Comparison of HDR-brachytherapy, Intensity-modulated Radiotherapy and Tomotherapy for Advanced Radiotherapy in Prostate Cancer

BACKGROUND/AIM

The aim of the study was to evaluate acute and late genitourinary (GU) and gastrointestinal (GI) toxicity in patients with high- or intermediate-risk prostate cancer.

PATIENTS AND METHODS

We evaluated data of patients from three Radiation Oncology Departments (Rome, Lübeck and Perugia). Patients treated in Rome underwent exclusive intensity-modulated-radiotherapy (IMRT) or IMRT plus high-dose-rate interventional radiotherapy (HDR-IRT). IMRT plus two fractions HDR-IRT was performed in Lübeck, while in Perugia Helical Tomotherapy was performed. The Common Toxicity Criteria for Adverse Event (Version 4.03) scale was used to describe acute and late toxicity.

RESULTS

At a median follow-up of 28 months, all 51 patients were alive and disease-free. Patients treated by HDR-IRT plus VMAT showed only G1-2 genitourinary- gastrointestinal (GU-GI) acute and late toxicity. Univariate analysis showed a lower risk of acute GU toxicity (p=0.048) in IMRT+HDR-IRT.

CONCLUSION

Low grade and less acute GU toxicity was observed in patients undergoing HDR-IRT boost.

PAIDEIA: pacemaker and implanted cardioverter defibrillator management in radiation therapy-a survey by the Young Group of the Italian Association of Radiotherapy and Clinical Oncology (AIRO)

INTRODUCTION

The management of patients bearing a cardiac implantable electronic device and needing a radiotherapy treatment is an important clinical scenario. The aim of this survey was to evaluate the level of awareness within the Italian Radiation Oncologist community on this topic.

MATERIALS AND METHODS

A survey was promoted by the Young Group of Italian Association of Radiotherapy and Clinical Oncology (AIRO) with a questionnaire made up of 22 questions allowing for multiple answers, which was administered, both online and on paper version. It was addressed to Radiation Oncologists, AIRO members, participating in the National Congress held in 2015.

RESULTS

A total of 113 questionnaires were collected back and analyzed (survey online: 50 respondents; paper version: 63). The answers showed a good level of awareness on the issue, but with a nonhomogeneous adherence to the different published guidelines (GL). There is a general low rate of referral for a preliminary cardiological evaluation in patients bearing PM/ICDs, in line with some published surveys; nevertheless, a focused attention to certain specific treatment factors and patient-centered point of view emerged.

CONCLUSIONS

A generally good awareness of this topic was shown but homogeneous application of GL was not observed, possibly due to the multiplicity of available GL. A prospective data collection could help to better clarify the shadows on this topics.

Radiotherapy Plus GnRH Analogue Versus High Dose Bicalutamide: A Case Control Study

BACKGROUND/AIM

Radiotherapy (RT) with adjuvant hormone therapy (HT) improves prognosis in prostate cancer (PC) patients. Gonadotrophin-releasing hormone agonist (GnRHa) with luteinizing hormone-releasing hormone (LH-RH) analogues is the standard HT. High-dose antiandrogen therapy also improves survival in patients with locally advanced PC. The aim of this study was to compare the results of patients treated with RT plus GnRHa and patients treated with RT plus bicalutamide.

PATIENTS AND METHODS

Our institutional PC database was used to identify patients treated with definitive or postoperative RT +/- HT which were included in this study.

RESULTS

Three hundred and eighteen patients were retrospectively reviewed (median follow-up=56 months). Five-year biochemical relapse-free survival was 85.5% and 88.3% in patients treated with GnRHa and bicalutamide, respectively (p=0.712).

CONCLUSION

Bicalutamide may be offered as an adjuvant treatment to RT in patients who refuse GnRHa because of related side effects. Furthermore, our study justifies randomized trials comparing RT plus GnRHa and RT plus bicalutamide.

Evaluation of Italian radiotherapy research from 1985 to 2005: preliminary analysis

AIM

The difficulty in conducting meaningful clinical research is a multifactorial issue, involving political, financial and cultural problems, which can lead to unexpected negative long-term consequences, in terms of knowledge advancement and impact on patient care. The aims of the present review were to evaluate the publications of Italian radiotherapy (RT) groups during a 20-year period and to verify whether research is still appealing to young radiation oncologists (ROs) in Italy.

METHODS

PubMed database was searched for English-language articles published by Italian groups from January 1985 to December 2005. Analyzed variables were: publication/year, kind of study, geographical area and age of the first author.

RESULTS

The systematic review identified 3291 articles: 1207 papers fulfilled the inclusion criteria. The number of Italian published papers increased during the examined period. Retrospective analyses, prospective phase I-II trials and literature reviews were 44, 20 and 14.5% of all published manuscripts, respectively. Randomized trials showed a mild increase from 2000 to 2005, but their absolute number remained low respect to other types of studies (4%). Northern Italy produced the very most of Italian research papers (58.7%). The age of the first/second author was evaluated on 716 papers: In more than 50% of cases, the first author was younger than 40.

CONCLUSION

Despite a general gradual improvement, RT clinical research suffers in Italy (as elsewhere) from insufficient funding, with a negative impact on evidence production. It is worth noting that clinical research is still appealing and accessible to junior Italian RO.

Moddicom: a complete and easily accessible library for prognostic evaluations relying on image features

Decision Support Systems (DSSs) are increasingly exploited in the area of prognostic evaluations. For predicting the effect of therapies on patients, the trend is now to use image features, i.e. information that can be automatically computed by considering images resulting by analysis. The DSSs application as predictive tools is particularly suitable for cancer treatment, given the peculiarities of the disease -which is highly localised and lead to significant social costs- and the large number of images that are available for each patient. At the state of the art, there exists tools that allow to handle image features for prognostic evaluations, but they are not designed for medical experts. They require either a strong engineering or computer science background since they do not integrate all the required functions, such as image retrieval and storage. In this paper we fill this gap by proposing Moddicom, a user-friendly complete library specifically designed to be exploited by physicians. A preliminary experimental analysis, performed by a medical expert that used the tool, demonstrates the efficiency and the effectiveness of Moddicom.

PRODIGE: PRediction models in prOstate cancer for personalized meDIcine challenGE

AIM

Identifying the best care for a patient can be extremely challenging. To support the creation of multifactorial Decision Support Systems (DSSs), we propose an Umbrella Protocol, focusing on prostate cancer.

MATERIALS & METHODS

The PRODIGE project consisted of a workflow for standardizing data, and procedures, to create a consistent dataset useful to elaborate DSSs. Techniques from classical statistics and machine learning will be adopted. The general protocol accepted by our Ethical Committee can be downloaded from cancerdata.org .

RESULTS

A standardized knowledge sharing process has been implemented by using a semi-formal ontology for the representation of relevant clinical variables.

CONCLUSION

The development of DSSs, based on standardized knowledge, could be a tool to achieve a personalized decision-making.

Standardized data collection to build prediction models in oncology: a prototype for rectal cancer

The advances in diagnostic and treatment technology are responsible for a remarkable transformation in the internal medicine concept with the establishment of a new idea of personalized medicine. Inter- and intra-patient tumor heterogeneity and the clinical outcome and/or treatment's toxicity's complexity, justify the effort to develop predictive models from decision support systems. However, the number of evaluated variables coming from multiple disciplines: oncology, computer science, bioinformatics, statistics, genomics, imaging, among others could be very large thus making traditional statistical analysis difficult to exploit. Automated data-mining processes and machine learning approaches can be a solution to organize the massive amount of data, trying to unravel important interaction. The purpose of this paper is to describe the strategy to collect and analyze data properly for decision support and introduce the concept of an 'umbrella protocol' within the framework of 'rapid learning healthcare'.

VATE: VAlidation of high TEchnology based on large database analysis by learning machine

SUMMARY 

The interaction between implementation of new technologies and different outcomes can allow a broad range of researches to be expanded. The purpose of this paper is to introduce the VAlidation of high TEchnology based on large database analysis by learning machine (VATE) project that aims to combine new technologies with outcomes related to rectal cancer in terms of tumor control and normal tissue sparing. Using automated computer bots and the knowledge for screening data it is possible to identify the factors that can mostly influence those outcomes. Population-based observational studies resulting from the linkage of different datasets will be conducted in order to develop predictive models that allow physicians to share decision with patients into a wider concept of tailored treatment.

Intensified adjuvant treatment of prostate carcinoma: feasibility analysis of a phase I/II trial

PURPOSE

To perform a preliminary feasibility acute and late toxicity evaluation of an intensified and modulated adjuvant treatment in prostate cancer (PCa) patients after radical prostatectomy.

MATERIAL AND METHODS

A phase I/II has been designed. Eligible patients were 79 years old or younger, with an ECOG of 0-2, previously untreated, histologically proven prostate adenocarcinoma with no distant metastases, pT2-4 N0-1, and with at least one of the following risk factors: capsular perforation, positive surgical margins, and seminal vesicle invasion. All patients received a minimum dose on tumor bed of 64.8 Gy, or higher dose (70.2 Gy; 85.4%), according to the pathological stage, pelvic lymph nodes irradiation (57.7%), and/or hormonal therapy (69.1%).

RESULTS

123 patients were enrolled and completed the planned treatment, with good tolerance. Median follow-up was 50.6 months. Grade 3 acute toxicity was only 2.4% and 3.3% for genitourinary (GU) and gastrointestinal (GI) tract, respectively. No patient had late grade 3 GI toxicity, and the GU grade 3 toxicity incidence was 5.8% at 5 years. 5-year BDSF was 90.2%.

CONCLUSIONS

A modulated and intensified adjuvant treatment in PCa was feasible in this trial. A further period of observation can provide a complete assessment of late toxicity and confirm the BDSF positive results.