A national survey of current practices of preparation and management of radical prostate radiotherapy patients during treatment

PSMA-PET-guided dose-escalated volumetric arc therapy for newly diagnosed lymph node-positive prostate cancer: 5 Year outcomes following the FROGG and EviQ node-positive guidelines

INTRODUCTION

The Royal Australian and New Zealand College of Radiologists (RANZCR) Faculty of Radiation Oncology Genitourinary Group (FROGG) guidelines and online EviQ protocols incorporate prostate-specific membrane antigen (PSMA) positron emission tomography (PET)-guided dose-escalated intensity-modulated radiation therapy (DE-IMRT) for newly diagnosed lymph node (LN) positive prostate cancer. We evaluated late toxicity and efficacy outcomes following the FROGG and EviQ approach.

METHODS

Patients with LN-positive-only metastases on PSMA-PET imaging were offered curative therapy with 3 months neoadjuvant androgen deprivation therapy (ADT) followed by DE-IMRT and 3 years adjuvant ADT. IMRT was delivered via volumetric arc therapy (VMAT). We aimed to deliver 81 Gy in 45 fractions (Fx) to the prostate and PET-positive LNs, and 60 Gy in 45 Fx to elective pelvic nodes, contoured using the PIVOTAL guidelines.

RESULTS

Forty-five patients were included. The median number of PET-positive nodes boosted was 2 (range 1-6) and median boost volume 1.16 cc (range 0.15-4.14). Seventeen (38%) patients had PET-positive nodes outside of PIVOTAL contouring guidelines. With 60 months median follow-up, disease-free, metastasis-free, prostate cancer-specific and overall survival were 88.1%, 95.3%, 100% and 91.5%. There were no in-field nodal failures. Late grade 1, 2 and 3 gastrointestinal toxicities occurred in 4%, 2% and 0% of patients, and genitourinary toxicity in 18%, 18% and 4%. Lower limb grade 2 lymphoedema occurred in three patients (7%).

CONCLUSION

Outcomes following FROGG guidelines and EviQ are promising, with high long-term disease control and low toxicity. Contouring guidelines require modification due to the high rate of PET-positive nodes demonstrated beyond recommended coverage.

Adequacy of sexual care information given to prostate cancer patients receiving radical external beam radiotherapy

Background:

Despite the acknowledged value of providing prostate radiotherapy patients with sexual dysfunction (SD) information, there is little evidence related to patient perceptions of this or the extent to which information is provided to them. This study aimed to critically evaluate the quality and format of SD information given to patients before, during and after radical EBRT to treat prostate cancer.

Method:

Members of UK prostate cancer support groups were asked to complete an anonymous online survey tool seeking opinions of the SD information they were given before, during and after external beam radiotherapy (EBRT).

Results:

There were 56 responses to the survey with over 42% of respondents reporting that they had not received any SD information. Of those who did, 78·1% (25/32) received information before the start of EBRT. Physicians were the most involved in the provision of SD information, with nurses and therapeutic radiographers being underutilised. Responses were mostly negative, or neutral regarding the quality of SD information and the information received about impact on relationships, psychological and emotional health. Many participants wanted more information and support.

Conclusion:

This study demonstrates that prostate cancer patients who have undergone radical EBRT have not received adequate information relating to potential sexual function side effects and the psychological and emotional effects of SD. This information should be included in verbal and written information provided at all stages of the radiotherapy pathway.

Bladder filling in patients undergoing prostate radiotherapy on a MR-linac: The dosimetric impact

The implementation of adaptive radiotherapy for prostate cancer compensates for inter-fraction motion, at the penalty of increased time in room. The subsequent increase in bladder filling may impact dosimetry, which we have investigated on ten patients treated on the MR-linac. Patients drank water before treatment, to achieve a bladder volume of 200-300 cm3. Bladder and bowel were re-outlined offline on 140 images and plans recalculated. All mandatory bladder dose constraints and 99.1% of bowel constraints were achieved at time of treatment, despite varying bladder volumes and varying adherence to original bladder filling guidance.

Bowel and bladder reproducibility in image guided radiation therapy for prostate cancer: Results of a patterns of practice survey

Purpose

Optimal management of patients with prostate cancer (PCa) to achieve bowel and bladder reproducibility for radiation therapy (RT) and the appropriate planning target volume (PTV) expansions for use with modern image guidance is uncertain. We surveyed American Society of Radiation Oncology radiation oncologists to ascertain practice patterns for definitive PCa RT with respect to patient instructions and set up, daily image guidance, and subsequent PTV expansions.

Methods and Materials

A pattern of practice survey was sent to American Society of Radiation Oncology radiation oncologists who self-identified as specializing in PCa. Respondents identified the fractionation regimens routinely used, and their practices regarding diet, bowel, and bladder instructions for patients with PCa before RT simulation and throughout treatment. Questions regarding PTV margins, daily set up practices, and use of image guidance were included.

Results

Of 190 respondents, 158 reported using conventional fractionation (CFx), 49 moderate hypofractionation (MHFx), and 61 stereotactic body radiation therapy (SBRT). Diet modifications during RT were advised by 84% of respondents, treatment with full bladder by 96%, and bowel instructions by 78%. Prescription of bowel medication was higher for respondents using SBRT (95.1%) versus those using CFx/MHFx (55.1%; 34.7%). The most common implantable device reported was fiducial markers, with increased use in SBRT (86.0%; 68.9%) versus CFx/MHFx. Cone beam computed tomography was the most common daily imaging technique across fractionation regimens. SBRT showed correlation between PTV margin expansions, fiducial marker use, and image guidance.

Conclusions

Survey results indicate heterogeneity in treatment modality, dose, patient instructions, and PTV expansions used by radiation oncologists in the treatment of patients with PCa. Further investigation to define appropriate patient instructions on bowel preparation to maximize target reproducibility in PCa is needed, as is continued guidance on evidence-based approaches for image guidance and PTV margin selection.

Rectal spacers in patients with prostate cancer undergoing radiotherapy: A survey of UK uro-oncologists

AIM

To understand the awareness and use of rectal spacers for prostate cancer patients undergoing radical radiotherapy in the United Kingdom.

METHODS

An expert-devised online questionnaire was completed by members of the British Uro-oncology Group (BUG).

RESULTS

Sixty-three specialists completed the survey (50% of BUG members at that point in time). Only 37% had used rectal spacers, mostly for private patients or those with pre-existing bowel conditions. However, many (68%) would like to use these devices in future. More than 70% of the uro-oncologists felt that bowel toxicity was underreported, but 60% believed that the use of radiotherapy without bowel toxicity was achievable with the use of rectal spacers.

CONCLUSIONS

The current use of rectal spacers by UK uro-oncologists for patients with localised or locally advanced prostate cancer receiving radiotherapy is low and largely restricted by resourcing issues.

Are simple verbal instructions sufficient to ensure that bladder volume does not deteriorate prostate position reproducibility during spot scanning proton therapy?

Objectives:

The purpose of this study is to investigate whether verbal instructions are sufficient for bladder volume (BV) control not to deteriorate prostate position reproducibility in image-guided spot scanning proton therapy (SSPT) for localized prostate cancer.

Methods:

A total of 268 treatment sessions in 12 consecutive prostate cancer patients who were treated with image-guided SSPT with fiducial markers were retrospectively analyzed. In addition to strict rectal volume control procedures, simple verbal instructions to void urine one hour before the treatment were used here. The BV was measured by a Bladder Scan just before the treatment, and the prostate motion was measured by intraprostatic fiducial markers and two sets of X-ray fluoroscopy images. The correlation between the BV change and prostate motion was assessed by linear mixed-effects models and systematic and random errors according to the reproducibility of the BV.

Results:

The mean absolute BV change during treatment was from −98.7 to 86.3 ml (median 7.1 ml). The mean absolute prostate motion of the patients in the left-right direction was −1.46 to 1.85 mm; in the cranial-caudal direction it was −6.10 to 3.65 mm, and in the anteroposterior direction −1.90 to 5.23 mm. There was no significant relationship between the BV change and prostate motion during SSPT. The early and late genitourinary and gastrointestinal toxicity was minimal with a minimum follow up of 4.57 years.

Conclusions:

Simple verbal instructions about urination was suggested to be sufficient to control the BV not to impact on the prostate motion and clinical outcomes in image-guided SSPT. Careful attention to BV change is still needed when the seminal vesicle is to be treated.

Advances in knowledge:

Our data demonstrated that there was no apparent relationship between BV changes and prostate position reproducibility and simple verbal instruction about urination could be sufficient for image-guided SSPT.

Bladder volume reproducibility after water consumption in patients with prostate cancer undergoing radiotherapy: A systematic review and meta-analysis

Background

To minimize toxicity due to radiotherapy in patients with prostate cancer, high bladder volume reproducibility is essential. Water consumption is often used to increase bladder volume reproducibility, but the optimal amount of water required to be consumed remains unclear. We aimed to analyzed the relationship between water consumption and bladder volume reproducibility in patients undergoing radiotherapy for prostate cancer.

Methods

We conducted a systematic review and meta-analysis of randomized controlled trials and cohort studies that assessed bladder volume change after water consumption in patients with prostate cancer undergoing radiotherapy. MEDLINE, Embase, and Cochrane Central Register of Controlled Trials were searched for relevant studies published from database inception up until July 4, 2020. The Newcastle–Ottawa Scale was used to evaluate the risk of bias in the included studies. The outcome was the mean difference (MD) of bladder volume after water consumption, evaluated through meta-analysis using a random-effects model.

Results

Ten cohort studies and one randomized controlled trial with a total of 417 patients were included. For 300–400 ml water consumption, the bladder volume MD between during treatment and at computer tomography-simulation (95% confidence interval [CI]) was −11.97 (−51.68 to 27.74), was −45.99 (−82.85 to −9.13) for 500–540 ml water consumption and −45.92 (−78.86 to −12.98) for water consumption until full-bladder sensation was reached.

Conclusion

Consuming 300–400 ml of water potentially leads to the best bladder volume reproducibility; moreover, the higher the water consumption volume, the lower the bladder volume reproducibility.

Impact of a low FODMAP diet on the amount of rectal gas and rectal volume during radiotherapy in patients with prostate cancer - a prospective pilot study

Background

Small inter- and intrafractional prostate motion was shown to be a prerequisite for precise radiotherapy (RT) of prostate cancer (PCa) to achieve good local control and low rectal toxicity. As rectal gas and rectal volume are known to have a relevant effect on prostate motion, this study aims to reduce these parameters by using a Low FODMAP Diet (LFD) and to show feasibility of this intervention.

Methods

We compared a prospective intervention group (IG, n = 25) which underwent RT for PCa and whose patients were asked to follow a LFD during RT with a retrospective control group (CG, n = 25) which did not get any dietary advice. In the planning CT scan and all available cone beam CT scans rectal gas was classified based on a semiquantitative score (scale from 1 to 5) and rectal volume was measured. Furthermore, patients’ compliance was evaluated by a self-assessment questionnaire.

Results

Clinical and treatment characteristics were well balanced between both groups. A total of 266 (CG, 10.6 per patient) and 280 CT scans (IG, 11.2 per patient), respectively, were analysed. The frequency distribution of gas scores differed significantly from each other (p < .001) with the IG having lower scores. Rectal volume was smaller in the IG (64.28 cm³, 95% CI 60.92–67.65 cm³, SD 28.64 cm³) than in the CG (71.40 cm³, 95% CI 66.47–76.32 cm³, SD 40.80 cm³) (p = .02). Mean intrapatient standard deviation as a measure for the variability of rectal volume was 22 cm³ in the IG and 23 cm³ in the CG (p = .81). Patients’ compliance and contentment were satisfying.

Conclusions

The use of a LFD significantly decreased rectal gas and rectal volume. LFD was feasible with an excellent patients’ compliance. However, prospective trials with a larger number of patients and a standardized evaluation of gastrointestinal toxicity and quality of life are reasonable.

Trial registration

German Clinical Trials Register, DRKS00012955. Registered 29 August 2017 - Retrospectively registered, https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00012955