Stereotactic ablative body radiotherapy for primary kidney cancer (TROG 15.03 FASTRACK II): a non-randomised phase 2 trial.

BACKGROUND: Stereotactic ablative body radiotherapy (SABR) is a novel non-invasive alternative for patients with primary renal cell cancer who do not undergo surgical resection. The FASTRACK II clinical trial investigated the efficacy of SABR for primary renal cell cancer in a phase 2 trial. METHODS: This international, non-randomised, phase 2 study was conducted in seven centres in Australia and one centre in the Netherlands. Eligible patients aged 18 years or older had biopsy-confirmed diagnosis of primary renal cell cancer, with only a single lesion; were medically inoperable, were at high risk of complications from surgery, or declined surgery; and had an Eastern Cooperative Oncology Group performance status of 0-2. A multidisciplinary decision that active treatment was warranted was required. Key exclusion criteria were a pre-treatment estimated glomerular filtration rate of less than 30 mL/min per 1·73 m2, previous systemic therapies for renal cell cancer, previous high-dose radiotherapy to an overlapping region, tumours larger than 10 cm, and direct contact of the renal cell cancer with the bowel. Patients received either a single fraction SABR of 26 Gy for tumours 4 cm or less in maximum diameter, or 42 Gy in three fractions for tumours more than 4 cm to 10 cm in maximum diameter. The primary endpoint was local control, defined as no progression of the primary renal cell cancer, as evaluated by the investigator per Response Evaluation Criteria in Solid Tumours (version 1.1). Assuming a 1-year local control of 90%, the null hypothesis of 80% or less was considered not to be worthy of proceeding to a future randomised controlled trial. All patients who commenced trial treatment were included in the primary outcome analysis. This trial is registered with ClinicalTrials.gov, NCT02613819, and has completed accrual. FINDINGS: Between July 28, 2016, and Feb 27, 2020, 70 patients were enrolled and initiated treatment. Median age was 77 years (IQR 70-82). Before enrolment, 49 (70%) of 70 patients had documented serial growth on initial surveillance imaging. 49 (70%) of 70 patients were male and 21 (30%) were female. Median tumour size was 4·6 cm (IQR 3·7-5·5). All patients enrolled had T1-T2a and N0-N1 disease. 23 patients received single-fraction SABR of 26 Gy and 47 received 42 Gy in three fractions. Median follow-up was 43 months (IQR 38-60). Local control at 12 months from treatment commencement was 100% (p<0·0001). Seven (10%) patients had grade 3 treatment-related adverse events, with no grade 4 adverse events observed. Grade 3 treatment-related adverse events were nausea and vomiting (three [4%] patients), abdominal, flank, or tumour pain (four [6%]), colonic obstruction (two [3%]), and diarrhoea (one [1%]). No treatment-related or cancer-related deaths occurred. INTERPRETATION: To our knowledge, this is the first multicentre prospective clinical trial of non-surgical definitive therapy in patients with primary renal cell cancer. In a cohort with predominantly T1b or larger disease, SABR was an effective treatment strategy with no observed local failures or cancer-related deaths. We observed an acceptable side-effect profile and renal function after SABR. These outcomes support the design of a future randomised trial of SABR versus surgery for primary renal cell cancer. FUNDING: Cancer Australia Priority-driven Collaborative Cancer Research Scheme.

Radical cystectomy or trimodality therapy for muscle-invasive bladder cancer: a qualitative study exploring patient priorities and counselling needs when making a treatment choice.

BACKGROUND: This study aims to explore the priorities and counselling needs of patients with muscle-invasive bladder cancer faced with a decision between radical cystectomy and trimodality therapy. METHODS: We performed a qualitative study according to the phenomenological approach. Sixteen muscle-invasive bladder cancer survivors who underwent radical cystectomy or trimodality therapy completed a semi-structured interview between May 2022 and February 2023. Patients were recruited via Ghent University Hospital and a patient organisation. Data were analysed with inductive thematic analysis by a multi-disciplinary team using an iterative approach and investigators' triangulation. RESULTS: Four main priorities determining the treatment decision were identified. (1) curing the disease; (2) health-related quality of life (physical, mental and social); (3) confidence in the treatment, which was mainly based on trust in the clinician; and (4) personal attributes. Trust in the clinician can be achieved by fulfilling the patient's information needs (accurate, complete, clear, impartial, personalised, realistic, and transparent information), ensuring accessibility of the clinician, and creating a clear and personalised treatment plan, involving patients to the extend they desire. Many patients considered a patient decision aid as a valuable asset in this process. CONCLUSION: Priorities vary between patients with muscle-invasive bladder cancer. Identifying individual priorities and offering personalised information about them is crucial for ensuring trust in the clinician and confidence in the treatment. Use of a patient decision aid can be beneficial in this process.

Development of a Management Algorithm for Acute and Chronic Radiation Urethritis and Cystitis.

OBJECTIVE: The purpose of this review was to summarize the current literature on the assessment and treatment of radiation urethritis and cystitis (RUC) for the development of an evidenced-based management algorithm. MATERIAL AND METHODS: The PubMed/MEDLINE database was searched by a multidisciplinary group of experts in January 2021. RESULTS: In total, 48 publications were identified. Three different types of RUC can be observed in clinical practice: inflammation-predominant, bleeding-predominant, and the combination of inflammation- and bleeding-RUC. There is no consensus on the optimal treatment of RUC. Inflammation-predominant RUC should be treated symptomatically based on the existence of bothersome storage or voiding lower urinary tract symptom as well as on pain. When bleeding-predominant RUC has occurred, hydration and hyperbaric oxygen therapy (HOT) should be used first and, if HOT is not available, oral drugs instead (sodium pentosane polysulfate, aminocaproic acid, immunokine WF 10, conjugated estrogene, or pentoxifylline + vitamin E). If local bleeding persists, focal therapy of bleeding vessels with a laser or electrocoagulation is indicated. In case of generalized bleeding, intravesical installation should be initiated (formalin, aluminium salts, and hyaluronic acid/chondroitin). Vessel embolization is a less invasive treatment with potentially less complications and good clinical outcomes. Open- or robot-assisted surgery is indicated in patients with permanent, life-threatening bleeding, or fistulae. CONCLUSIONS: Treatment of RUC, if not self-limiting, should be done according to the type of RUC and in a stepwise approach. Conservative/medical treatment (oral and topic agents) should primarily be used before invasive (transurethral) treatments.

Platinum exposure and cause-specific mortality among patients with testicular cancer.

BACKGROUND: Although testicular cancer (TC) treatment has been associated with severe late morbidities, including second malignant neoplasms (SMNs) and ischemic heart disease (IHD), cause-specific excess mortality has been rarely studied among patients treated in the platinum era. METHODS: In a large, multicenter cohort including 6042 patients with TC treated between 1976 and 2006, cause-specific mortality was compared with general population mortality rates. Associations with treatment were assessed with proportional hazards analysis. RESULTS: With a median follow-up of 17.6 years, 800 patients died; 40.3% of these patients died because of TC. The cumulative mortality was 9.6% (95% confidence interval [CI], 8.5%-10.7%) 25 years after TC treatment. In comparison with general population mortality rates, patients with nonseminoma experienced 2.0 to 11.6 times elevated mortality from lung, stomach, pancreatic, rectal, and kidney cancers, soft-tissue sarcomas, and leukemia; 1.9-fold increased mortality (95% CI, 1.3-2.8) from IHD; and 3.9-fold increased mortality (95% CI, 1.5-8.4) from pneumonia. Seminoma patients experienced 2.5 to 4.6 times increased mortality from stomach, pancreatic, bladder cancer and leukemia. Radiotherapy and chemotherapy were associated with 2.1 (95% CI, 1.8-2.5) and 2.5 times higher SMN mortality (95% CI, 2.0-3.1), respectively, in comparison with the general population. In a multivariable analysis, patients treated with platinum-containing chemotherapy had a 2.5-fold increased hazard ratio (HR; 95% CI, 1.8-3.5) for SMN mortality in comparison with patients without platinum-containing chemotherapy. The HR for SMN mortality increased 0.29 (95% CI, 0.19-0.39) per 100 mg/m2 platinum dose administered (Ptrend  < .001). IHD mortality was increased 2.1-fold (95% CI, 1.5-4.2) after platinum-containing chemotherapy in comparison with patients without platinum exposure. CONCLUSIONS: Platinum-containing chemotherapy is associated with a dose-dependent increase in the risk of SMN mortality.

Development and validation of a patient decision aid for prostate Cancer therapy: from paternalistic towards participative shared decision making.

BACKGROUND: Patient decision aids (PDAs) can support the treatment decision making process and empower patients to take a proactive role in their treatment pathway while using a shared decision-making (SDM) approach making participatory medicine possible. The aim of this study was to develop a PDA for prostate cancer that is accurate and user-friendly. METHODS: We followed a user-centered design process consisting of five rounds of semi-structured interviews and usability surveys with topics such as informational/decisional needs of users and requirements for PDAs. Our user-base consisted of 8 urologists, 4 radiation oncologists, 2 oncology nurses, 8 general practitioners, 19 former prostate cancer patients, 4 usability experts and 11 healthy volunteers. RESULTS: Informational needs for patients centered on three key factors: treatment experience, post-treatment quality of life, and the impact of side effects. Patients and clinicians valued a PDA that presents balanced information on these factors through simple understandable language and visual aids. Usability questionnaires revealed that patients were more satisfied overall with the PDA than clinicians; however, both groups had concerns that the PDA might lengthen consultation times (42 and 41%, respectively). The PDA is accessible on http://beslissamen.nl/ . CONCLUSIONS: User-centered design provided valuable insights into PDA requirements but challenges in integrating diverse perspectives as clinicians focus on clinical outcomes while patients also consider quality of life. Nevertheless, it is crucial to involve a broad base of clinical users in order to better understand the decision-making process and to develop a PDA that is accurate, usable, and acceptable.

Risk of diabetes after para-aortic radiation for testicular cancer.

BACKGROUND: While the risk of diabetes is increased following radiation exposure to the pancreas among childhood cancer survivors, its association among testicular cancer (TC) survivors has not been investigated. METHODS: Diabetes risk was studied in 2998 1-year TC survivors treated before 50 years of age with orchidectomy with/without radiotherapy between 1976 and 2007. Diabetes incidence was compared with general population rates. Treatment-specific risk of diabetes was assessed using a case-cohort design. RESULTS: With a median follow-up of 13.4 years, 161 TC survivors were diagnosed with diabetes. Diabetes risk was not increased compared to general population rates (standardised incidence ratios (SIR): 0.9; 95% confidence interval (95% CI): 0.7-1.1). Adjusted for age, para-aortic radiotherapy was associated with a 1.66-fold (95% CI: 1.05-2.62) increased diabetes risk compared to no radiotherapy. The excess hazard increased with 0.31 with every 10 Gy increase in the prescribed radiation dose (95% CI: 0.11-0.51, P = 0.003, adjusted for age and BMI); restricted to irradiated patients the excess hazard increased with 0.33 (95% CI: -0.14 to 0.81, P = 0.169) with every 10 Gy increase in radiation dose. CONCLUSION: Compared to surgery only, para-aortic irradiation is associated with increased diabetes risk among TC survivors.

Dynamics of rectal balloon implant shrinkage in prostate VMAT : Influence on anorectal dose and late rectal complication risk.

PURPOSE: To assess the effect of a shrinking rectal balloon implant (RBI) on the anorectal dose and complication risk during the course of moderately hypofractionated prostate radiotherapy. METHODS: In 15 patients with localized prostate cancer, an RBI was implanted. A weekly kilovolt cone-beam computed tomography (CBCT) scan was acquired to measure the dynamics of RBI volume and prostate-rectum separation. The absolute anorectal volume encompassed by the 2 Gy equieffective 75 Gy isodose (V75Gy) was recalculated as well as the mean anorectal dose. The increase in estimated risk of grade 2-3 late rectal bleeding (LRB) between the start and end of treatment was predicted using nomograms. The observed acute and late toxicities were evaluated. RESULTS: A significant shrinkage of RBI volumes was observed, with an average volume of 70.4% of baseline at the end of the treatment. Although the prostate-rectum separation significantly decreased over time, it remained at least 1 cm. No significant increase in V75Gy of the anorectum was observed, except in one patient whose RBI had completely deflated in the third week of treatment. No correlation between mean anorectal dose and balloon deflation was found. The increase in predicted LRB risk was not significant, except in the one patient whose RBI completely deflated. The observed toxicities confirmed these findings. CONCLUSIONS: Despite significant decrease in RBI volume the high-dose rectal volume and the predicted LRB risk were unaffected due to a persistent spacing between the prostate and the anterior rectal wall.

TROG 15.03 phase II clinical trial of Focal Ablative STereotactic Radiosurgery for Cancers of the Kidney - FASTRACK II.

BACKGROUND: Stereotactic ablative body radiotherapy (SABR) is a non-invasive alternative to surgery to control primary renal cell cancer (RCC) in patients that are medically inoperable or at high-risk of post-surgical dialysis. The objective of the FASTRACK II clinical trial is to investigate the efficacy of SABR for primary RCC. METHODS: FASTRACK II is a single arm, multi-institutional phase II study. Seventy patients will be recruited over 3 years and followed for a total of 5 years. Eligible patients must have a biopsy confirmed diagnosis of primary RCC with a single lesion within a kidney, have ECOG performance ≤2 and be medically inoperable, high risk or decline surgery. Radiotherapy treatment planning is undertaken using four dimensional CT scanning to incorporate the impact of respiratory motion. Treatment must be delivered using a conformal or intensity modulated technique including IMRT, VMAT, Cyberknife or Tomotherapy. The trial includes two alternate fractionation schedules based on tumour size: for tumours ≤4 cm in maximum diameter a single fraction of 26Gy is delivered; and for tumours > 4 cm in maximum diameter 42Gy in three fractions is delivered. The primary outcome of the study is to estimate the efficacy of SABR for primary RCC. Secondary objectives include estimating tolerability, characterising overall survival and cancer specific survival, estimating the distant failure rate, describing toxicity and renal function changes after SABR, and assessment of cost-effectiveness of SABR compared with current therapies. DISCUSSION: The present study design allows for multicentre prospective validation of the efficacy of SABR for primary RCC that has been observed from prior single institutional and retrospective series. The study also allows assessment of treatment related toxicity, overall survival, cancer specific survival, freedom from distant failure and renal function post therapy. TRIAL REGISTRATION: Clinicaltrials.gov NCT02613819 , registered Nov 25th 2015.

Development of an isotoxic decision support system integrating genetic markers of toxicity for the implantation of a rectum spacer.

INTRODUCTION: Previous studies revealed that dose escalated radiotherapy for prostate cancer patients leads to higher tumor control probabilities (TCP) but also to higher rectal toxicities. An isotoxic model was developed to maximize the given dose while controlling the toxicity level. This was applied to analyze the effect of an implantable rectum spacer (IRS) and extended with a genetic test of normal tissue radio-sensitivity. A virtual IRS (V-IRS) was tested using this method. We hypothesized that the patients with increased risk of toxicity would benefit more from an IRS. MATERIAL AND METHODS: Sixteen localized prostate cancer patients implanted with an IRS were included in the study. Treatment planning was performed on computed tomography (CT) images before and after the placement of the IRS and with a V-IRS. The normal tissue complication probability (NTCP) was calculated using a QUANTEC reviewed model for Grade > =2 late rectal bleeding and the number of fractions of the plans were adjusted until the NTCP value was under 5%. The resulting treatment plans were used to calculate the TCP before and after placement of an IRS. This was extended by adding the effect of two published genetic single nucleotide polymorphisms (SNP's) for late rectal bleeding. RESULTS: The median TCP resulting from the optimized plans in patients before the IRS was 75.1% [32.6-90.5%]. With IRS, the median TCP is significantly higher: 98.9% [80.8-99.9%] (p < .01). The difference in TCP between the V-IRS and the real IRS was 1.8% [0.0-18.0%]. Placing an IRS in the patients with SNP's improved the TCP from 49.0% [16.1-80.8%] and 48.9% [16.0-72.8%] to 96.3% [67.0-99.5%] and 90.1% [49.0-99.5%] (p < .01) respectively for either SNP. CONCLUSION: This study was a proof-of-concept for an isotoxic model with genetic biomarkers with a V-IRS as a multifactorial decision support system for the decision of a placement of an IRS.

Implantation of a biodegradable rectum balloon implant: tips, Tricks and Pitfalls.

INTRODUCTION: A rectum balloon implant (RBI) is a new device to spare rectal structures during prostate cancer radiotherapy. The theoretical advantages of a RBI are to reduce the high radiation dose to the anterior rectum wall, the possibility of a post-implant correction, and their predetermined shape with consequent predictable position. OBJECTIVE: To describe, step-by-step, our mini-invasive technique for hands-free transperineal implantation of a RBI before start of radiotherapy treatment. MATERIALS AND METHODS: We provide step-by-step instructions for optimization of the transperineal implantation procedure performed by urologists and/or radiation oncologists experienced with prostate brachytherapy and the use of the real-time bi-plane transrectal ultrasonography (TRUS) probe. A RBI was performed in 15 patients with localised prostate cancer. Perioperative side-effects were reported. RESULTS: We provide 'tips and tricks' for optimizing the procedure and proper positioning of the RBI. Please watch the animation, see video in https://vimeo.com/205852376/789df4fae4. The side-effects included mild discomfort to slight pain at the perineal region in 8 out of 15 patients. Seven patients (47%) had no complaints at all. Two patients developed redness of the skin, where prompt antibiotic regimen was started with no further sequelae. One patient revealed a temporary urine retention, which resolved in a few hours following conservative treatment. Further no perioperative complications occurred. CONCLUSION: This paper describes in detail the implantation procedure for an RBI. It is a feasible, safe and very well-tolerated procedure.

Modern clinical research: How rapid learning health care and cohort multiple randomised clinical trials complement traditional evidence based medicine.

BACKGROUND: Trials are vital in informing routine clinical care; however, current designs have major deficiencies. An overview of the various challenges that face modern clinical research and the methods that can be exploited to solve these challenges, in the context of personalised cancer treatment in the 21st century is provided. AIM: The purpose of this manuscript, without intending to be comprehensive, is to spark thought whilst presenting and discussing two important and complementary alternatives to traditional evidence-based medicine, specifically rapid learning health care and cohort multiple randomised controlled trial design. Rapid learning health care is an approach that proposes to extract and apply knowledge from routine clinical care data rather than exclusively depending on clinical trial evidence, (please watch the animation: http://youtu.be/ZDJFOxpwqEA). The cohort multiple randomised controlled trial design is a pragmatic method which has been proposed to help overcome the weaknesses of conventional randomised trials, taking advantage of the standardised follow-up approaches more and more used in routine patient care. This approach is particularly useful when the new intervention is a priori attractive for the patient (i.e. proton therapy, patient decision aids or expensive medications), when the outcomes are easily collected, and when there is no need of a placebo arm. DISCUSSION: Truly personalised cancer treatment is the goal in modern radiotherapy. However, personalised cancer treatment is also an immense challenge. The vast variety of both cancer patients and treatment options makes it extremely difficult to determine which decisions are optimal for the individual patient. Nevertheless, rapid learning health care and cohort multiple randomised controlled trial design are two approaches (among others) that can help meet this challenge.

Chronic radiation proctitis: tricks to prevent and treat.

OBJECTIVE: The purpose of this study was to give an overview of the measures used to prevent chronic radiation proctitis (CRP) and to provide an algorithm for the treatment of CRP. METHODS: Medical literature databases including PubMed and Medline were screened and critically analyzed for relevance in the scope of our purpose. RESULTS: CRP is a relatively frequent late side effect (5-20%) and mainly dependent on the dose and volume of irradiated rectum. Radiation treatment (RT) techniques to prevent CRP are constantly improving thanks to image-guided RT and intensity-modulated RT. Also, newer techniques like protons and new devices such as rectum spacers and balloons have been developed to spare rectal structures. Biopsies do not contribute to diagnosing CRP and should be avoided because of the risk of severe rectal wall damage, such as necrosis and fistulas. There is no consensus on the optimal treatment of CRP. A variety of possibilities is available and includes topical and oral agents, hyperbaric oxygen therapy, and endoscopic interventions. CONCLUSIONS: CRP has a natural history of improving over time, even without treatment. This is important to take into account when considering these treatments: first be conservative (topical and oral agents) and be aware that invasive treatments can be very toxic.

Rare type of Bellini Duct Carcinoma in a Patient With Cacchi-Ricci Disease: A Case Report and Mini-Review.

Medullary sponge kidney (MSK) is an uncommon kidney malformation, characterized by cystic dilatation of the precalyceal papillary collecting ducts. Urography and computed tomography scan represent the gold standard to detect this congenital disorder. A clear diagnosis is not always feasible, especially in the presence of a concomitant renal mass, which in turn can be difficult to detect in MSK patients. When conventional imaging is inconclusive, a renal biopsy can be considered in doubtful cases. Here, we report a unique case of a Bellini duct carcinoma in a patient with MSK and we review the literature on this complex condition.

A unified strategy to focal brachytherapy incorporating transperineal biopsy, image fusion, and real-time implantation with and without rectal spacer simulated in prostate phantoms.

Purpose: To develop an approach to the diagnosis and treatment of prostate cancer using one platform for fusion biopsy, followed by focal gland ablation utilizing permanent prostate brachytherapy with and without a rectal spacer. Material and methods: Prostate phantoms containing multiparametric magnetic resonance imaging (mpMRI) regions of interest (ROI) underwent fusion biopsy, followed by image co-registration of positive sites to a treatment planning brachytherapy program. A partial hemi-ablation and both posterior lobes using a Mick applicator and linked stranded seeds were simulated. Dummy sources were modeled as iodine-125 (125I) with a prescribed dose of at least 210 Gy to gross tumor (GTV) and clinical target volume (CTV), as defined by mpMRI visible ROI and surrounding negative biopsy sites. Computer tomograms (CT) were performed post-implant prior to and after rectal spacer insertion. Different prostate and rectal constraints were compared with and without the spacer. Results: The intra-operative focal volumes of CTV ranged from 6.2 to 14.9 cc (mean, 11.3 cc), and the ratio of focal volume/whole prostate volume ranged between 0.19 and 0.42 (mean, 0.31). The intra- and post-operative mean focal D90 of GTV, CTV, and for the entire prostate gland was 265 Gy and 235 Gy, 214 Gy and 213 Gy, and 66.1 Gy and 57 Gy, respectively. On average, 13 mm separation was achieved between the prostate and the rectum (range, 12-14 mm) on post-operative CT. The mean doses in Gy to 2 cc of the rectum (D2cc) without spacer vs. with spacer were 39.8 Gy vs. 32.6 Gy, respectively. Conclusions: Doses above 200 Gy and the implantation of seeds in clinically significant region for focal therapy in phantoms are feasible. All rectal dosimetric parameters improved for the spacer implants, as compared with the non-spacer implants. Further validation of this concept is warranted in clinical trials.

The value of PROMs for predicting erectile dysfunction in prostate cancer patients with Bayesian network.

Purpose: This study aims to develop and externally validate a clinically plausible Bayesian network structure to predict one-year erectile dysfunction in prostate cancer patients by combining expert knowledge with evidence from data using clinical and Patient-reported outcome measures (PROMs) data. In addition, compare and contrast structures that stem from PROM information and routine clinical data. Summary of background: For men with localized prostate cancer, choosing the optimal treatment can be challenging since each option comes with different side effects, such as erectile dysfunction, which negatively impacts their quality of life. Our previous findings demonstrate that logistic regression models are able to identify patients at high risk of erectile dysfunction. However, methods such as Bayesian networks may be more successful, as they intricately represent the causal relations between the variables. Patients and methods: 946 prostate cancer patients from 65 Dutch hospitals were considered to develop the Bayesian network structure. Continuous variables were discretized before analysis based on expert opinions and literature. Patients with missing information and variables with more than 25% of missing information were excluded. Prostate cancer treating physicians first determined the relationships (arcs) between the available variables. The structures were then modified based on algorithmically derived structures using the hill-climbing algorithm. Structural Performance was evaluated based on the area under the curve (AUC) values and calibration plots on the training and test data. Results: BMI and prostate volume via MRI were excluded from this analysis due to their high percentage of missingness (>45 %). The final cohort was reduced to 505 and 216 after excluding 157 and 68 patients with missing information, respectively. The AUC of the PROM structure was better than the clinical structure in both the train and test data. The structure that combined both sources of information had an AUC value of 0.94 (0.92 - 0.96) and 0.84171 (0.77 91) in the train and test data, respectively. Conclusion: Bayesian network structures derived from PROM information by complimenting expert knowledge with evidence from the data produce a clinically plausible structure that is more performant than structures from clinical data. Our study supports the growing global recognition of incorporating the patient's perspective in outcomes research for better decision-making and optimal outcomes. However, a structure that combines both sources of information gives a more holistic view of the patient with actionable insights and improved discriminative power.

Prospective, Randomized Controlled Pivotal Trial of Biodegradable Balloon Rectal Spacer for Prostate Radiation Therapy.

PURPOSE/OBJECTIVES: Rectal spacers have been shown to reduce rectal side effects in patients receiving prostate radiation. However, concerns remain regarding precise and reproducible gel injection. We evaluated efficacy and safety of a novel rectoprostatic spacer balloon that allows potential for controlled, adaptable deployment. This study tested co-primary hypotheses: (1) balloon spacer would result in ≥25% reduction of rectal V70 in >75% of subjects and (2) implantation procedure-related and rectal ≥grade 1 adverse events within 6 months (duration ≥2 days, Common Terminology Criteria for Adverse Events 4.0) would be noninferior in balloon versus control subjects. METHODS AND MATERIALS: A total of 222 subjects were enrolled at 16 centers. All patients had T1-T3 prostate cancer without magnetic resonance imaging evidence of posterior extraprostatic invasion. Randomization was 2:1 (balloon: control) and subject-blinded. Patients underwent transperineal transrectal ultrasound axial and sagittal-guided fiducial placement ± balloon, followed by Intensity-Modulated Radiation Therapy (81 Gy in 1.8 Gy fractions or biologically equivalent hypofractionated dose). For efficacy comparisons, plans were generated by a central core lab on pre- and postimplant computed tomography scans. RESULTS: The primary efficacy endpoint was met, with 97.9% of balloon subjects (139/142) having rectal V70 reduction >25% (P < .001). Mean V70 was 7.0 % pre- versus 1.1% postimplant. The primary safety endpoint was met with balloon subjects experiencing fewer ≥grade 1 events, 18% versus 23% (P < .001 for noninferiority). On predefined secondary endpoint of ≥grade 2 events, rates trended lower in balloon subjects (4.3% vs 6.5%, P = .527). Mean perirectal spacing was 19 ± 3.7 mm and maintained through radiation treatment (18 ± 3.9 mm). Balloon resorption was observed on 6-month computed tomography in 98.5% (133/135) of subjects. The Expanded Prostate Cancer Index quality of life instrument was collected throughout study, and did not differ statistically between the study arms. CONCLUSIONS: Biodegradable rectal spacer balloon was effective in significantly reducing dose to rectum, and associated with decreased cumulative rectal plus implantation-related adverse events. Balloon resorption was consistently observed by 6 months.

Development and Internal Validation of a Novel Nomogram Predicting the Outcome of Salvage Radiation Therapy for Biochemical Recurrence after Radical Prostatectomy in Patients without Metastases on Restaging Prostate-specific Membrane Antigen Positron Emission Tomography/Computed Tomography.

Background and objective: Owing to the greater use of prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) in patients with biochemical recurrence (BCR) of prostate cancer (PCa) after robot-assisted radical prostatectomy (RARP), patient selection for local salvage radiation therapy (sRT) has changed. Our objective was to determine the short-term efficacy of sRT in patients with BCR after RARP, and to develop a novel nomogram predicting BCR-free survival after sRT in a nationwide contemporary cohort of patients who underwent PSMA PET/CT before sRT for BCR of PCa, without evidence of metastatic disease. Methods: All 302 eligible patients undergoing PCa sRT in four reference centers between September 2015 and August 2020 were included. We conducted multivariable logistic regression analysis using a backward elimination procedure to develop a nomogram for predicting biochemical progression of PCa, defined as prostate-specific antigen (PSA) ≥0.2 ng/ml above the post-sRT nadir within 1 yr after sRT. Key findings and limitations: Biochemical progression of disease within 1 yr after sRT was observed for 56/302 (19%) of the study patients. The final predictive model included PSA at sRT initiation, pathological grade group, surgical margin status, PSA doubling time, presence of local recurrence on PSMA PET/CT, and the presence of biochemical persistence (first PSA result ≥0.1 ng/ml) after RARP. The area under the receiver operating characteristic curve for this model was 0.72 (95% confidence interval 0.64-0.79). Using our nomogram, patients with a predicted risk of >20% had a 30.8% chance of developing biochemical progression within 1 yr after sRT. Conclusions: Our novel nomogram may facilitate better patient counseling regarding early oncological outcome after sRT. Patients with high risk of biochemical progression may be candidates for more extensive treatment. Patient summary: We developed a new tool for predicting cancer control outcomes of radiotherapy for patients with recurrence of prostate cancer after surgical removal of their prostate. This tool may help in better counseling of these patients with recurrent cancer regarding their early expected outcome after radiotherapy.

Pretrial Quality Assurance for Hypofractionated Salvage Radiation Therapy After Prostatectomy in the Multi-Institutional PERYTON-trial.

Purpose: The PERYTON trial is a multicenter randomized controlled trial that will investigate whether the treatment outcome of salvage external beam radiation therapy (sEBRT) will be improved with hypofractionated radiation therapy. A pretrial quality assurance (QA) program was undertaken to ensure protocol compliance within the PERYTON trial and to assess variation in sEBRT treatment protocols between the participating centers. Methods and Materials: Completion of the QA program was mandatory for each participating center (N = 8) to start patient inclusion. The pretrial QA program included (1) a questionnaire on the center-specific sEBRT protocol, (2) a delineation exercise of the clinical target volume (CTV) and organs at risk, and (3) a treatment planning exercise. All contours were analyzed using the pairwise dice similarity coefficient (DSC) and the 50th and 95th percentile Hausdorff distance (HD50 and HD95, respectively). The submitted treatment plans were reviewed for protocol compliance. Results: The results of the questionnaire showed that high-quality, state-of-the-art radiation therapy techniques were used in the participating centers and identified variations of the sEBRT protocols used concerning the position verification and preparation techniques. The submitted CTVs showed significant variation, with a range in volume of 29 cm3 to 167 cm3, a mean pairwise DSC of 0.52, and a mean HD50 and HD95 of 2.3 mm and 24.4 mm, respectively. Only in 1 center the treatment plan required adaptation before meeting all constraints of the PERYTON protocol. Conclusions: The pretrial QA of the PERYTON trial demonstrated that high-quality, but variable, radiation techniques were used in the 8 participating centers. The treatment planning exercise confirmed that the dose constraints of the PERYTON protocol were feasible for all participating centers. The observed variation in CTV delineation led to agreement on a new (image-based) delineation guideline to be used by all participating centers within the PERYTON trial.

Adaptive 3D image-guided brachytherapy: a strong argument in the debate on systematic radical hysterectomy for locally advanced cervical cancer.

PURPOSE: To evaluate the outcomes of patients with locally advanced cervical cancer treated with three-dimensional image-guided brachytherapy (IGABT) after concomitant chemoradiation (CCRT). MATERIALS AND METHODS: Data from patients treated with CCRT followed by magnetic resonance imaging-guided or computed tomography-guided pulsed-dose-rate brachytherapy, performed according to the Groupe Européen de Curiethérapie-European Society for Radiotherapy and Oncology guidelines, were reviewed. At first, stage I or II patients systematically underwent radical hysterectomy or were offered a randomized study evaluating hysterectomy. Then, hysterectomy was limited to salvage treatment. RESULTS: Of 163 patients identified, 27% had stage IB, 57% had stage II, 12% had stage III, and 3% had stage IVA disease. The mean dose delivered (in 2-Gy dose equivalents) to 90% of the high-risk clinical target volume was 78.1 ± 9.6 Gy, whereas the doses delivered to organs at risk were maintained under the usual thresholds. Sixty-one patients underwent a hysterectomy. Macroscopic residual disease was found in 13 cases. With a median follow-up of 36 months (range, 5-79 months), 45 patients had relapsed. The 3-year overall survival rate was 76%. Local and pelvic control rates were 92% and 86%, respectively. According to the Common Toxicity Criteria 3.0, 7.4% of patients experienced late grade 3 or 4 toxicity. Most of those had undergone postradiation radical surgery (2.9% vs. 14.8; p = .005). CONCLUSION: IGABT combined with CCRT provides excellent locoregional control rates with low treatment-related morbidity, justifying the elimination of hysterectomy in the absence of obvious residual disease. Distant metastasis remains an important first relapse and may warrant more aggressive systemic treatment.

Focal salvage high-dose-rate brachytherapy with implantable rectum spacer for locally recurrent prostate cancer after initial low-dose-rate with grade 3 rectal toxicity.

Purpose: Locally recurrent prostate cancer after previous radiation therapy remains challenging. One of the curative options for these patients is salvage brachytherapy. There are no reports available on the use of a biodegradable rectal balloon implantation (RBI) in combination with brachytherapy in patients with recurrent prostate cancer after previous radiotherapy. Case presentation: Here, we report on a patient with a local recurrence at five years after previous low-dose-rate brachytherapy with a prescribed dose of 145 Gray (Gy) for a low-risk prostate adenocarcinoma. The patient experienced grade 3 rectal toxicity, which was resolved at the time of local recurrence. He was treated with focal high-dose-rate (HDR) brachytherapy of 2 fr. × 13 Gy after RBI implantation. Four years post-salvage treatment, there was no evidence of biochemical recurrence according Phoenix definition, and no gastro-intestinal or genitourinary toxicity. Conclusions: This case describes the use of RBI implantation in combination with a focal salvage HDR in a patient with recurrent disease, with significant initial grade 3 rectal toxicity after previous irradiation. The use of a biodegradable RBI proved to be a promising solution for such a patient; however, this method needs to be further investigated.