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.
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.
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.
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.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Several studies have established that radiotherapy (RT) in combination with immunotherapy (IO) has a strong synergistic effect. RT changes the tumor microenvironment, generates local inflammation ...reactions, and enhances immunostimulatory effects, which are able to assist IO with improving local and systemic tumor control. In several pre-clinical reports, RT in combination with IO reveals regression of tumors locally (irradiated sites) and systemically (non-irradiated sites). Several clinical trials are currently running, mostly as phase I and II studies. This article provides an overview of the randomized, prospective reported and recruiting phase 3 clinical trials of RT in combination with IO. To date, three phase 3 trials have been published on RT and sequential IO with variable results, ranging from no significant difference (Kwon
et al.
, START) to absolute differences in overall survival of 13.5% after 3 years (PACIFIC), respectively. No phase 3 randomized trials have been published on the simultaneous combination of RT with IO. Thirty trials are presently under way, and still recruiting patients to quantify the response to RT with IO. These studies fall into three categories of research interests: (I) to discover an enhancement effect of IO as induction therapy with RT; (II) to determine the additional effect of concurrent IO on the local effect of RT; and (III) to determine the additional effect of adjuvant or consolidation IO on the local effect of RT. Most of the ongoing studies are a combination of these interests, with 15 trials evaluating the concurrent RT+IO with IO consolidation strategy. The results in coming years will provide more insights in the role of RT as an activator of the immune system, the effect of IO as local sensitizer of RT, the optimal sequencing of IO with RT, and the total RT doses needed to obtain the optimal local and systemic effect.
Purpose
The use of ultrasound imaging is not widespread in prostate cancer radiotherapy workflows, despite several advantages (eg, allowing real‐time volumetric organ tracking). This can be partially ...attributed to the need for a trained operator during acquisition and interpretation of the images. We introduce and evaluate an algorithm that can propose a patient‐specific transperineal ultrasound probe setup, based on a CT scan and anatomical structure delineations. The use of this setup during the simulation and treatment stage could improve usability of ultrasound imaging for relatively untrained operators (radiotherapists with less than 1 yr experience with ultrasound).
Methods
The internal perineum boundaries of three prostate cancer patients were identified based on bone masks extracted from their CT scans. After projection of these boundaries to the skin and exclusion of specific areas, this resulted in a skin area accessible for transperineal ultrasound probe placement in clinical practice. Several possible probe setups on this area were proposed by the algorithm and the optimal setup was automatically selected. In the end, this optimal setup was evaluated based on a comparison with a corresponding transperineal ultrasound volume acquired by a radiation oncologist.
Results
The algorithm‐proposed setups allowed visualization of 100% of the clinically required anatomical structures, including the whole prostate and seminal vesicles, as well as the adjacent edges of the bladder and rectum. In addition, these setups allowed visualization of 94% of the anatomical structures, which were also visualized by the physician during the acquisition of an actual ultrasound volume.
Conclusion
Provided that the ultrasound probe setup proposed by the algorithm, is properly reproduced on the patient, it allows visualization of all clinically required structures for image guided radiotherapy purposes. Future work should validate these results on a patient population and optimize the workflow to enable a relatively untrained operator to perform the procedure.
•Hyaluronic acid (HA) is an implantable rectum spacer used to decrease rectal radiation dose in prostate cancer radiotherapy.•Hyaluronidase (HAS) is an enzyme that degrades HA, when wrongly ...positioned.•A ratio of HA:HAS of 1:2 has already a decrease of half of volume on the 2nd day.
To determine a dose response relationship of disintegration of a hyaluronic acid (HA) and hyaluronidase (HAS) used in prostate cancer radiotherapy.
Five in-vitro models are applicated with 3 ml (ml) HA. For dissolution varying doses of HAS were used: 6 ml, 3 ml, 1.5 ml, and 0 ml. One ml contains 150 International Units (IU). Each HAS was added with saline till the complementary amount of 6 ml. One phantom was solely implanted with a HA 3 ml acting as a control. Length, width and height were measured on different time points: 1st day 4 times, 2nd day 3 times, third day 2 times, and then once daily during one week, with a final measurement 2 weeks after implantation. The experiments were performed in duplicate to exclude variations and confirm the results.
The fastest dissolution was observed with the highest concentration of HAS, already observed at the first time point 2 h after implantation, with volume decrease of 50% on the second day, and less than 1 ml residue (33%) on day 4. The 2 other concentrations of HAS also showed a volume decrease, with less than 2 ml (66%) on day 4. All the applied quantities of HAS are observed with a residue of less than 1 ml after 7 days. After 14 days the control phantom and the saline filled one remains on steady state volume (3 ml).
A dose response was observed by HAS injection: highest volumes of HAS dissolute most swiftly. Using a ratio of HA:HAS of 1:2 results in a decrease to half of initial volume within 24 h. This is of special interest when used in clinical practice following erroneous positioning, and dissolution is urgently needed.
The aim of this study is to build a decision support system (DSS) to select radical prostatectomy (RP) or external beam radiotherapy (EBRT) for low- to intermediate-risk prostate cancer patients. We ...used an individual state-transition model based on predictive models for estimating tumor control and toxicity probabilities. We performed analyses on a synthetically generated dataset of 1000 patients with realistic clinical parameters, externally validated by comparison to randomized clinical trials, and set up an in silico clinical trial for elderly patients. We assessed the cost-effectiveness (CE) of the DSS for treatment selection by comparing it to randomized treatment allotment. Using the DSS, 47.8% of synthetic patients were selected for RP and 52.2% for EBRT. During validation, differences with the simulations of late toxicity and biochemical failure never exceeded 2%. The in silico trial showed that for elderly patients, toxicity has more influence on the decision than TCP, and the predicted QoL depends on the initial erectile function. The DSS is estimated to result in cost savings (EUR 323 (95% CI: EUR 213–433)) and more quality-adjusted life years (QALYs; 0.11 years, 95% CI: 0.00–0.22) than randomized treatment selection.
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.
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.
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.
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.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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.
To describe, step-by-step, our mini-invasive technique for hands-free transperineal implantation of a RBI before start of radiotherapy treatment.
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.
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.
This paper describes in detail the implantation procedure for an RBI. It is a feasible, safe and very well-tolerated procedure.
•Implantable rectum spacers (IRS) separate the ano-rectal wall (ARW) from the prostate.•Dose-surface maps (DSMs) are a tool to take spatio-dosimetric info into account.•Spatio-dosimetric differences ...in ARW DSMs exist comparing IMRT with and without IRS.•IRS reduces the lateral and longitudinal extent of areas >50 Gy.•IRS reduces these high-dose areas in anterior and superior-inferior directions.
To evaluate spatial differences in dose distributions of the ano-rectal wall (ARW) using dose-surface maps (DSMs) between prostate cancer patients receiving intensity-modulated radiation therapy with and without implantable rectum spacer (IMRT+IRS; IMRT−IRS, respectively), and to correlate this with late gastro-intestinal (GI) toxicities using validated spatial and non-spatial normal-tissue complication probability (NTCP) models.
For 26 patients DSMs of the ARW were generated. From the DSMs various shape-based dose measures were calculated at different dose levels: lateral extent, longitudinal extent, and eccentricity. The contiguity of the ARW dose distribution was assessed by the contiguous-DSH (cDSH). Predicted complication rates between IMRT+IRS and IMRT−IRS plans were assessed using a spatial NTCP model and compared against a non-spatial NTCP model.
Dose surface maps are generated for prostate radiotherapy using an IRS. Lateral extent, longitudinal extent and cDSH were significantly lower in IMRT+IRS than for IMRT−IRS at high-dose levels. Largest significant differences were observed for cDSH at dose levels >50 Gy, followed by lateral extent at doses >57 Gy, and longitudinal extent in anterior and superior-inferior directions. Significant decreases (p = 0.01) in median rectal and anal NTCPs (respectively, Gr 2 late rectal bleeding and subjective sphincter control) were predicted when using an IRS.
Local-dose effects are predicted to be significantly reduced by an IRS. The spatial NTCP model predicts a significant decrease in Gr 2 late rectal bleeding and subjective sphincter control. Dose constraints can be improved for current clinical treatment planning.
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.
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.
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.
Clinicaltrials.gov NCT02613819 , registered Nov 25th 2015.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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 (V
75Gy
) 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 V
75Gy
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.