Pelvic Complications After Prostate Cancer Radiation Therapy and Their Management: An International Collaborative Narrative Review

Risk of Secondary Malignancies After Pelvic Radiation: A Population-based Analysis

Background and objective

Radiation therapy has increasingly been used in the management of pelvic malignancies. However, the use of radiation continues to pose a risk of a secondary malignancy to its recipients. This study investigates the risk of secondary malignancy development following radiation for primary pelvic malignancies.

Methods

A retrospective cohort review of the Surveillance, Epidemiology, and End Results database from 1975 to 2016 was performed. Primary pelvic malignancies were subdivided based on the receipt of radiation, and secondary malignancies were stratified as pelvic or nonpelvic to investigate the local effect of radiation.

Key findings and limitations

A total of 2 102 192 patients were analyzed (1 189 108 with prostate, 315 026 with bladder, 88 809 with cervical, 249 535 with uterine, and 259 714 with rectal/anal cancer). The incidence rate (defined as cases per 1000 person years) of any secondary malignancies (including but not limited to secondary pelvic malignancies) was higher in radiation patients than in nonradiation patients (incidence rate ratio [IRR] 1.04, confidence interval [CI] 1.03-1.05), with significantly greater rates noted in radiation patients with prostate (IRR 1.22, CI 1.21-1.24), uterine (IRR 1.34), and cervical (IRR 1.80, CI 1.72-1.88) cancer. While the overall incidence rate of any secondary pelvic malignancy was lower in radiation patients (IRR 0.79, CI 0.78-0.81), a greater incidence was still noted in the same cohorts including radiation patients with prostate (IRR 1.42, CI 1.39-1.45), uterine (IRR 1.15, CI 1.08-1.21), and cervical (IRR 1.72, CI 1.59-1.86) cancer.

Conclusions and clinical implications

Except for localized cervical cancer, when put in the context of median overall survival, the impact of radiation likely does not carry enough weight to change practice patterns. Radiation for pelvic malignancies increases the risk for several secondary malignancies, and more specifically, secondary pelvic malignancies, but with a relatively low absolute risk of secondary malignancies, the benefits of radiation warrant continued use for most pelvic malignancies. Practice changes should be considered for radiation utilization in malignancies with excellent cancer-specific survival such as cervical cancer.

Patient summary

The use of radiation for the management of pelvic malignancies induces a risk of secondary malignancies to its recipients. However, the absolute risk being low, the benefits of radiation warrant its continued use, and a change in practice patterns is unlikely.

Dysbiosis of gut microbiota and metabolites is associated with radiation-induced colorectal fibrosis and is restored by adipose-derived mesenchymal stem cell therapy

AIMS

This study aimed to investigate the effects of adipose-derived mesenchymal stem cells (ADSCs) on radiation-induced colorectal fibrosis (RICF) along with the associated dysbiosis of gut microbiota and metabolites.

MAIN METHODS

Fecal microbiota were assessed through 16S rRNA gene sequencing, and the fecal metabolome was characterized using liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry. The correlation between microbiota and metabolome data was explored.

KEY FINDINGS

ADSC injection demonstrated a significant restoration of radiation-induced intestinal damage in vivo. At the phylum level, irradiated rats exhibited an increase in Bacteroidota and Campilobacterota, and a decrease in Firmicutes and Desulfobacterota, contrasting with the ADSC treatment group. Metabolomic analysis revealed 72 differently expressed metabolites (DEMs) from gas chromatography-mass spectrometry and 284 DEMs from liquid chromatography-mass spectrometry in the radiation group compared to the blank group. In the ADSC treatment group versus the radiation group, 36 DEMs from gas chromatography-mass spectrometry and 341 DEMs from liquid chromatography-mass spectrometry were identified. KEGG enrichment analysis implicated pathways such as steroid hormone biosynthesis, gap junction, primary bile acid biosynthesis, citrate cycle, cAMP signaling pathway, and alanine, aspartate, and glutamate metabolism during RICF progression and after treated with ADSCs. Correlation analysis highlighted the role of ADSCs in modulating the metabolic process of Camelledionol in fecal Bacteroides.

SIGNIFICANCE

These findings underscore the potential of ADSCs in reversing dysbiosis and restoring normal colonic flora in the context of RICF, offering valuable insights for therapeutic interventions targeting radiation-induced complications.

Mental health outcomes in a population-based cohort of patients with prostate cancer

BACKGROUND

Few studies have evaluated mental health disorders comprehensively among patients with prostate cancer on long-term follow-up. The primary aim of our study was to assess the incidence of mental health disorders among patients with prostate cancer compared with a general population cohort. A secondary aim was to investigate potential risk factors for mental health disorders among patients with prostate cancer.

METHODS

Cohorts of 18 134 patients with prostate adenocarcinomas diagnosed between 2004 and 2017 and 73470 men without cancer matched on age, birth state, and follow-up time were identified. Mental health diagnoses were identified from electronic health records and statewide health-care facilities data. Cox proportional hazard models were used to estimate hazard ratios. All statistical tests were 2-sided.

RESULTS

The hazard ratios for mood disorders, including depression, among prostate cancer survivors increased for all follow-up periods compared with the general population. The hazard ratios for any mental illness increased with Hispanic, Black, or multiple races; people who were underweight or obese; those with advanced prostate cancer; and those undergoing their first course cancer treatment. We also observed statistically significantly increased hazard ratios for mental health disorders among patients with lower socioeconomic status (P < .0001) and increasing duration of androgen-deprivation therapy (P = .0348). Prostate cancer survivors had a 61% increased hazard ratio for death with a depression diagnosis.

CONCLUSION

Prostate cancer diagnosis was associated with a higher risk of mental health disorders compared with the general population, which was observed as long as 10-16 years after cancer diagnosis. Providing long-term mental health support may be beneficial to increasing life expectancy for patients with prostate cancer.

Major Complications and Adverse Events Related to Use of SpaceOAR Hydrogel for Prostate Cancer Radiotherapy

OBJECTIVE

To determine the prevalence and severity of SpaceOARTM-related adverse events using the Manufacturer and User Facility Device Experience (MAUDE) database.

METHODS

We analyzed SpaceOAR-related adverse event reports in the Manufacturer and User Facility Device Experience (MAUDE) database from January 2015 to May 2023. For each report, the event type, associated device and patient problems, event description, event timing, and event severity stratified by the Common Terminology Criteria for Adverse Events version 5.0 (CTCAE) grading system were recorded.

RESULTS

From 2015 to 2022, 206,619 SpaceOAR devices were sold. From January 2015 to May 2023, we identified 981 reports describing 990 SpaceOAR-related adverse events. Malfunctions were the most common event type (N=626), followed by patient injuries (N=350) with few reported deaths (N=5). Device positioning problems were the most frequent device issue (N=686). Pain was the most reported patient problem (N=216). Abscesses and fistulas related to the device were each reported in 91 events. A noteworthy portion of relevant adverse events occurred before the initiation of radiation (N=35, 22.4%), suggesting the device, rather than the radiation, was responsible. In total, 470 (50.2%) and 344 (36.7%) of the adverse events were CTCAE grade 1 and 2, respectively. There were 123 (13.1%) events that were CTCAE grade ≥ 3.

CONCLUSION

We identified multiple reports of SpaceOAR-related adverse events, many of which are more serious than have been reported in clinical trials. While SpaceOAR use is common, suggesting these events are rare, these data highlight the need for continued postmarket surveillance.

Health-related Quality of Life in Patients With Urethral Stenosis After Radiation Treatment for Prostate Cancer

OBJECTIVE

To evaluate patient-reported quality of life (PRQoL) in patients presenting with membranous urethral stenosis after prostate radiotherapy. Urethral stenosis is an under-reported complication after prostate radiotherapy with a particular deficiency in PRQoL.

METHODS

Patients presenting with urethral stenosis after radiotherapy were retrospectively reviewed from 2004 to 2022. PRQoL was assessed via patient survey using the Expanded Prostate Cancer Index Composite for Clinical Practice (EPIC-CP).

RESULTS

Two hundred thirty patients were identified at a mean age of 67.7years and mean time to stricture diagnosis of 63.6months' postradiotherapy. Of 87 patients completing the survey, 29.9% recalled being aware of urethral stenosis as a potential complication and 51.7% had documentation of urethral stenosis as a potential complication. 33.5% of patients underwent urethroplasty, 59.6% repeat endoscopic treatment and 6.1% an indwelling catheter. 64.4% of patients reported urinary dysfunction as a "moderate" or "big" problem, 66.7% reported frequent or total incontinence, 64.4% required daily pad use and 50.6% reported incontinence as either a "moderate" or "big" problem. 85.0% reported poor or absent orgasmic dysfunction and 88.5% reported erections insufficient for sexual activity. Additionally, 47.1% of patients reported rectal pain and 31.0% reported dysuria. Depressive symptoms and fatigue were reported by 41.4% and 60.9% of patients respectively.

CONCLUSION

Urethral stenosis after radiotherapy is a clinically complex entity with a broad scope of associated symptoms including high rates of patient-reported incontinence, voiding dysfunction, sexual dysfunction, pain, bowel dysfunction and depression. This multifocal nature combined with often insidious presentation and patient unawareness creates a uniquely challenging condition to treat.

Do Swiss urologists and Swiss internists screen themselves and their relatives for prostate cancer? A questionnaire study

PURPOSE

Prostate-specific antigen (PSA) screening for men at risk of prostate cancer is controversial. The current recommendation is to raise awareness of prostate cancer and offer PSA screening in accordance with shared decision- making. Whether the possibility of a PSA screen is discussed with the patient depends on the treating physician, but data on physicians' attitudes towards PSA screening are scarce. This study aimed to examine internists' and urologists' personal PSA screening activity as an indicator of their attitude towards PSA screening.

MATERIALS AND METHODS

Members of the Swiss Society of Urology and the Swiss Society of General Internal Medicine were asked in 08/2020 to anonymously complete an online survey about personal PSA screening behaviour for themselves, their fathers, brothers and partners. Categorical and continuous variables were compared by chi-squared tests and t-tests, respectively.

RESULTS

In total, 190/295 (response rate: 64%) urologists and 893/7400 (response rate: 12%) internists participated in the survey. Of the participants, 297/1083 (27.4%) were female. Male urologists >50 years of age screened themselves more often than male internists >50 years of age (89% vs 70%, p <0.05). Furthermore, urologists reported recommending screening statistically significantly more often than internists to their brother, father or partner regardless of their sex (men: 38.1% vs 18.5%; p <0.05; women: 81.8% vs 32.2%; p <0.05).   CONCLUSIONS: Most participating male physicians >50 years of age have screened themselves for prostate cancer. Furthermore, PSA screening of relatives was significantly associated with the urology specialty. The reasons physicians screen themselves substantially more often than the public and why male and female urologists as well as male internists perform PSA screening more frequently in their private environment than female internists should be further examined.

Radiation-induced Fistulas in Patients With Prior Pelvic Radiotherapy for Prostate Cancer: A Systematic Review and Meta-analysis

OBJECTIVE

To systematically aggregate and summarize existing data on fistula prevalence among patients with a history of pelvic radiotherapy for prostate cancer.

MATERIALS AND METHODS

We queried PubMed, Embase, and Web of Science on October 7, 2020 for peer-reviewed publications pertaining to radiation-induced fistulas in the pelvis. For meta-analysis, we used the random-effects model. We used the I2 statistic to quantify heterogeneity and the Newcastle-Ottawa Scale to assess risk of bias.

RESULTS

Our final meta-analysis included 6 cohort studies with a total of 7665 patients exposed to pelvic radiotherapy between 1967 and 2013. Median follow-up time was 35.5 months (IQR 33.5-57.5). Pooled prevalence of radiation-induced fistula across all 6 cohort studies was 0.2% (95% CI: 0.1-0.4, I2 = 0.000%, P < .608). In subgroup analysis, we did not detect significant heterogeneity in fistula prevalence in patients who were re-irradiated (0.3%, 95% CI: 0.1-0.4; P = .762) or patients on concurrent chemotherapy (0.4%, 95% CI: -0.3 -1.2; P = .664) compared to those receiving their first course of radiotherapy alone. No randomized controlled trials met inclusion criteria due to ambiguous and inconsistent reporting language for fistula occurrence.

CONCLUSION

There is limited published literature reporting fistula as an adverse event of prostate cancer radiotherapy, especially in the medium and long-term period. Patients undergoing pelvic radiotherapy for prostate cancer appear at low short-term risk for developing fistulas. Adverse event reporting in randomized controlled trials merits greater granularity where fistulas should be reported with specificity rather than aggregating into broad categories of genitourinary or gastrointestinal adverse events.

Nanoparticles Targeted to Fibroblast Activation Protein Outperform PSMA for MRI Delineation of Primary Prostate Tumors

Accurate delineation of gross tumor volumes remains a barrier to radiotherapy dose escalation and boost dosing in the treatment of solid tumors, such as prostate cancer. Magnetic resonance imaging (MRI) of tumor targets has the power to enable focal dose boosting, particularly when combined with technological advances such as MRI-linear accelerator. Fibroblast activation protein (FAP) is overexpressed in stromal components of >90% of epithelial carcinomas. Herein, the authors compare targeted MRI of prostate specific membrane antigen (PSMA) with FAP in the delineation of orthotopic prostate tumors. Control, FAP, and PSMA-targeting iron oxide nanoparticles were prepared with modification of a lymphotropic MRI agent (FerroTrace, Ferronova). Mice with orthotopic LNCaP tumors underwent MRI 24 h after intravenous injection of nanoparticles. FAP and PSMA nanoparticles produced contrast enhancement on MRI when compared to control nanoparticles. FAP-targeted MRI increased the proportion of tumor contrast-enhancing black pixels by 13%, compared to PSMA. Analysis of changes in R2 values between healthy prostates and LNCaP tumors indicated an increase in contrast-enhancing pixels in the tumor border of 15% when targeting FAP, compared to PSMA. This study demonstrates the preclinical feasibility of PSMA and FAP-targeted MRI which can enable targeted image-guided focal therapy of localized prostate cancer.

Prevention of Radiation-Induced Bladder Injury: A Murine Study Using Captopril

PURPOSE

Pelvic radiation therapy (RT) can cause debilitating bladder toxicities but few clinical interventions exist to prevent injury or alleviate symptoms. From a large genome-wide association study in patients with prostate cancer it was previously reported that SNPs tagging AGT, part of the renin-angiotensin system (RAS), correlated with patient-reported late hematuria, identifying a potential targetable pathway to prevent RT-induced bladder injury. To investigate this association, we performed a preclinical study to determine whether RAS modulation protected the bladder against RT injury.

METHODS AND MATERIALS

C57BL/6 male mice were treated with an oral angiotensin converting enzyme inhibitor (ACEi: 0.3g/L captopril) 5 days before focal bladder X-irradiation with either single dose (SD) 30 Gy or 3 fractions of 8 Gy (8 Gy × 3 in 5 days). RT was delivered using XStrahl SARRP Muriplan CT-image guidance with parallel-opposed lateral beams. ACEi was maintained for 20 weeks post RT. Bladder toxicity was assessed using assays to identify local injury that included urinalysis, functional micturition, bladder-released exosomes, and histopathology, as well as an assessment of systemic changes in inflammatory-mediated circulating immune cells.

RESULTS

SD and fractionated RT increased urinary frequency and reduced the volume of individual voids at >14 weeks, but not at 4 weeks, compared with nonirradiated animals. Urothelial layer width was positively correlated with mean volume of individual voids (P = .0428) and negatively correlated with number of voids (P = .028), relating urothelial thinning to changes in RT-mediated bladder dysfunction. These chronic RT-induced changes in micturition patterns were prevented by captopril treatment. Focal bladder irradiation significantly increased the mean particle count of urine extracellular vesicles and the monocyte and neutrophil chemokines CCL2 and MIP-2, and the proportions of circulating inflammatory-mediated neutrophils and monocytes, which was also prevented by captopril. Exploratory transcriptomic analysis of bladder tissue implicated inflammatory and erythropoietic pathways.

CONCLUSIONS

This study demonstrated that systemic modulation of the RAS protected against and alleviated RT-induced late bladder injury but larger confirmatory studies are needed.

Outcomes of salvage high dose-rate brachytherapy with or without pelvic external beam radiotherapy in patients with palpable local recurrence of prostate cancer after radical prostatectomy

PURPOSE

This study aims to evaluate the outcomes and toxicities in patients with palpable local recurrence of prostate cancer after radical prostatectomy (RP), who were treated with salvage high dose-rate brachytherapy (HDR-BT) with or without pelvic external beam radiotherapy (EBRT).

METHODS

This retrospective review included patients with palpable local recurrence of prostate cancer after RP who underwent salvage HDR-BT at a single institution between 2002 and 2020. HDR-BT regimens included 950 cGy x 2 (N = 4) or 1500 cGy x 1 (N = 2) combined with EBRT; or monotherapy with 950 cGy x 4 (N = 1) or 800 cGy x 2 (N = 1). Toxicity was graded according to CTCAE Version 5.0.

RESULTS

A total of 8 patients were included. Median follow-up was 49 months (range: 9-223 months). Median age at time of salvage brachytherapy was 68 years (range: 59-85 years). Seven out of 8 patients were alive at last follow-up. There have been no locoregional recurrences. Three patients developed distant metastatic disease. One patient developed acute grade 3 urinary obstruction requiring catheterization, which lasted for 1 day postbrachytherapy. One patient developed late grade 3 urinary incontinence 18 months after brachytherapy. There were no other grade 2+ toxicities.

CONCLUSIONS

This study demonstrates the safety and efficacy of salvage HDR-BT in the setting of palpable local recurrence of prostate cancer after RP, with durable locoregional control and acceptable rates of toxicity. HDR-BT should be further explored as an option for dose-escalated salvage radiotherapy after prior radical prostatectomy.

A prospective, multicenter head-to-head comparative study in patients with primary high-risk prostate cancer investigating the bone lesion detection of conventional imaging and 18F-PSMA-PET/CT

PURPOSE

Prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) is an emerging staging tool for patients with primary high-risk prostate cancer (PCa). Patients with primary metastatic disease are staged using PSMA-PET/CT imaging, while previously published randomized clinical trials relied on conventional imaging (i.e., bone scintigraphy (BS) results. The aim of this study was to compare the ability of bone metastatic lesion detection and changes in staging for ¹⁸F-PSMA-PET/CT versus BS in high-risk PCa patients.

METHODS

79 patients with high-risk PCa were prospectively staged using BS and subsequent ¹⁸F-PSMA-PET/CT before initial therapy. Patients who presented with a BS showing no metastases represented Group 1, and patients with a BS showing low-volume disease according to the CHAARTED criteria (<4 bone metastases, no metastases outside vertebral column or pelvis and no visceral metastases) represented Group 2. Metastatic risk group according to CHAARTED and treatment strategies based on both imaging modalities were assessed.

RESULTS

A change of CHAARTED risk group was observed in 9/70 (12.8%) of patients in Group 1. In Group 2, a change of risk group was found in 66.7% of patients, due to either upstaging (4/9 patients (44.4%)) and downstaging (2/9 patients (22.2%)). Treatment changes due to use of a different imaging modality occurred in almost 20% of patients.

CONCLUSION

In patients with negative for cancer results on BS, upstaging on ¹⁸F-PSMA-PET/CT occurred only infrequently. Moreover, ¹⁸F-PSMA-PET/CT resulted in both upstaging and downstaging in a substantial subset of patients with low-volume metastatic disease on BS. Treatment changes occurred in almost 20% of cases depending on imaging results.

Surgical Tolerability and Frailty in Elderly Patients Undergoing Robot-Assisted Radical Prostatectomy: A Narrative Review

Simple Summary

Life expectancy in Western countries and East Asian countries has incremented over the past decades, resulting in a rapidly aging world, while in general, radical prostatectomy (RP) is not recommended in elderly men aged ≥75 years. Together with the evolving technique of robotic surgeries, surgical indications for RP should be reconsidered in ‘elderly’ and ‘frail’ men, since this procedure has now become one of the safest and most effective cancer treatments for prostate cancer. One important element to determine surgical indications is surgical tolerability. However, evidence is scarce regarding the surgical tolerability in elderly men undergoing robot-assisted radical prostatectomy (RARP). In this review, we focused on the surgical tolerability in ‘elderly’ and/or ‘frail’ men undergoing RARP, with the intent to provide up-to-date information on this matter and to support the decision making of therapeutic options in this spectrum of patients.

Abstract

Robot-assisted radical prostatectomy (RARP) has now become the gold standard treatment for localized prostate cancer. There are multiple elements in decision making for the treatment of prostate cancer. One of the important elements is life expectancy, which the current guidelines recommend as an indicator for choosing treatment options. However, determination of life expectancy can be complicated and difficult in some cases. In addition, surgical tolerability is also an important issue. Since frailty may be a major concern, it may be logical to use geriatric assessment tools to discriminate ‘surgically fit’ patients from unfit patients. Landmark studies show two valid models such as the phenotype model and the cumulative deficit model that allow for the diagnosis of frailty. Many studies have also developed geriatric screening tools such as VES-13 and G8. These tools may have the potential to directly sort out unfit patients for surgery preoperatively.

Radiation therapy after radical prostatectomy is associated with higher other-cause mortality

PURPOSE

To test the association between external beam radiotherapy (EBRT) after radical prostatectomy (RP) vs RP only on rates of other-cause mortality (OCM) in men with prostate cancer (PCa).

PATIENTS AND METHODS

Within the 2004-2016 Surveillance, Epidemiology, and End Results database, we identified 181,849 localized PCa patients, of whom 168,041 received RP only vs 13,808 who received RP + EBRT. Cumulative incidence plots displayed OCM between RP vs RP + EBRT after propensity score matching for age, PSA, clinical T- and N-stages, and biopsy Gleason scores. Multivariable competing risks regression models addressed OCM, accounting prostate cancer-specific mortality (CSM) as a competing event. Stratifications were made according to low- vs intermediate- vs high-risk groups and additionally according to age groups of ≤ 60, 61-70, and ≥ 71 years, within each risk group.

RESULTS

In low-, intermediate-, and high-risk patients, RP + EBRT rates were 2.7, 5.4 and 17.0%, respectively. After matching, 10-year OCM rates between RP and RP + EBRT were 7.7 vs 16.2% in low-, 9.4 vs 13.6% in intermediate-, and 11.4 vs 13.5% in high-risk patients (all p < 0.001), which, respectively, resulted in multivariable HR of 2.1, 1.3, and 1.2 (all p < 0.001). In subgroup analyses, excess OCM was recorded in low-risk RP + EBRT patients of all age groups (all p ≤ 0.03), but only in the older age group in intermediate-risk patients (61-70 years, p = 0.03) and finally, only in the oldest age group in high-risk patients (≥ 71 years, p = 0.02).

CONCLUSION

Excess OCM was recorded in patients exposed to RT after RP. Its extent was most pronounced in low-risk patients, decreased in intermediate-risk patients, and was lowest in high-risk patients.

Pelvic Radiation Disease

Pelvic radiation is increasingly being used for the neoadjuvant and definitive treatment of pelvic organ malignancy. While this treatment can be highly effective, and may assist in organ sparing, it is also associated with significant toxicity and devastating adverse events that need to be considered. In broad terms, pelvic radiation disease affects both the primary target organ as well as adjacent organs and soft tissue structures, with complications that can be classified and graded according to consensus criteria. The complication grade is often modality, dose, and area dependent. The most common manifestations are proctitis, cystitis, recto-urethral fistula, ureteric stricture, and bone involvement. Toxicity can be misdiagnosed for many years, resulting in significant management delays. Complications can be difficult to prevent and challenging to treat, requiring specialized multi-disciplinary input to achieve the best possible strategy to minimize impact and improve patient quality of life.

Radiation Proctitis: The Potential Role of Hyaluronic Acid in the Prevention and Restoration of Any Damage to the Rectal Mucosa among Prostate Cancer Patients Submitted to Curative External Beam Radiotherapy

Aim: To evaluate if hyaluronic acid reduces proctitis episodes with respect to corticosteroids in prostate cancer patients submitted to radical or adjuvant radiotherapy. Methods: A consecutive series of eligible patients received hyaluronic acid enemas as supportive care (experimental group, from January 2013 to June 2015). A historical group (control group), treated from October 2011 to December 2012, received beclomethasone dipropionate suppositories. We registered each patient’s data regarding acute and chronic proctitis. All patients were treated with static-intensity-modulated radiotherapy coupled to a daily set-up verification with orthogonal anterior–posterior/lateral X-ray pairs. Results: A total of 269 patients, 175 in the experimental group and 94 in the control group, was evaluated; 2 Gy/day (up to a total median dose of 80 Gy) and 2.7 Gy/day (up to a total median dose of 67.5 Gy) fractionation schemes were used for 216 and 53 patients, respectively. All patients had a good tolerance to radiotherapy, reporting no G3 or greater proctitis. No significant difference was reported concerning the total rate of proctitis between the two groups but only with respect to its grade: a higher G2 rate within the control group. There was no correlation between daily dose fractionation and toxicity grade. Conclusions: Hyaluronic acid enemas might be effective in reducing the severity of radiation proctitis.

Bladder surface dose modeling in prostate cancer radiotherapy: An analysis of motion-induced variations and the cumulative dose across the treatment

PURPOSE

To introduce a novel surface-based dose mapping method to improve quantitative bladder dosimetric assessment in prostate cancer (PC) radiotherapy.

METHODS

Based on the planning and daily pre and postfraction MRIs of 12 PC patients, bladder surface models (SMs) were generated on manually delineated contours and regionally aligned via surface-based registration. Subsequently, bladder surface dose models (SDMs) were created using face-wise dose sampling. To determine the bladder intrafractional and interfractional motion and dose variation, we performed a pose analysis between pre and postfraction bladder SMs, as well as surface mapping for fractional SMs. Discrepancies between the received dose, accumulated from daily SDMs, and the planned dose were then assessed on the corresponding SDMs. Complementary to the surface dose mapping, dose surface histogram (DSH)-based comparisons were also performed.

RESULTS

The intrafraction pose analysis revealed a significant (p < 0.05) bladder expansion, as well as an anterior/superior drift during the treatment. The intrafraction motion substantially altered dose to mid-bladder body, but not the bladder surface areas distal to or contiguous with the target. A similar pattern of dose variations was also detected by interfraction comparisons. With surface registration to the common SM, the cumulative bladder dose significantly differs from the planned dose. The discrepancy is evident in the mid-posterior range that corresponds to a mid- to high-dose region. The received DSH significantly differs from the planned DSH after permutation correction (p = 0.0122), while the overall surface-based comparison after multiple comparison correction is nonsignificant (p = 0.0800).

CONCLUSIONS

We developed a novel surface-based intra and interdose mapping framework applied to a unique daily MR dataset for image-guided radiotherapy. The framework identified significant intrafraction bladder positional changes, localized the intra and interfraction variations, and quantified planned versus received dose differences on the bladder surface. The result indicates the importance of adopting the motion-integrated bladder SDM for bladder dose management.

Radioactive Iodine-125 in Tumor Therapy: Advances and Future Directions

Radioactive iodine-125 (I-125) is the most widely used radioactive sealed source for interstitial permanent brachytherapy (BT). BT has the exceptional ability to deliver extremely high doses that external beam radiotherapy (EBRT) could never achieve within treated lesions, with the added benefit that doses drop off rapidly outside the target lesion by minimizing the exposure of uninvolved surrounding normal tissue. Spurred by multiple biological and technological advances, BT application has experienced substantial alteration over the past few decades. The procedure of I-125 radioactive seed implantation evolved from ultrasound guidance to computed tomography guidance. Compellingly, the creative introduction of 3D-printed individual templates, BT treatment planning systems, and artificial intelligence navigator systems remarkably increased the accuracy of I-125 BT and individualized I-125 ablative radiotherapy. Of note, utilizing I-125 to treat carcinoma in hollow cavity organs was enabled by the utility of self-expandable metal stents (SEMSs). Initially, I-125 BT was only used in the treatment of rare tumors. However, an increasing number of clinical trials upheld the efficacy and safety of I-125 BT in almost all tumors. Therefore, this study aims to summarize the recent advances of I-125 BT in cancer therapy, which cover experimental research to clinical investigations, including the development of novel techniques. This review also raises unanswered questions that may prompt future clinical trials and experimental work.

Management of Medium and Long Term Complications Following Prostate Cancer Treatment Resulting in Urinary Diversion - A Narrative Review

The purpose of this narrative review is to discuss and highlight recently published studies regarding the surgical management of patients suffering from prostate cancer treatment complications. Focus will be put on the recalcitrant and more complex cases which might lead to urinary diversion as a definite, last resort treatment. It is in the nature of every treatment, that complications will occur and be bothersome for both patients and physicians. A small percentage of patients following prostate cancer treatment (radical prostatectomy, radiation therapy, or other focal therapies) will suffer side effects and thus, will experience a loss of quality of life. These side effects can persist for months and even years. Often, conservative management strategies fail resulting in recalcitrant recurrences. Prostate cancer patients with "end-stage bladder," "devastated outlet," or a history of multiple failed interventions, are fortunately rare, but can be highly challenging for both patients and Urologists. In a state of multiple previous surgical procedures and an immense psychological strain for the patient, urinary diversion can offer a definite, last resort surgical solution for this small group of patients. Ideally, they should be transferred to centers with experience in this field and a careful patient selection is needed. As these cases are highly complex, a multidisciplinary approach is often necessary in order to guarantee an improvement of quality of life.

Evaluation and Management of Genitourinary Emergencies in Patients with Cancer

Background

Genitourinary emergencies in cancer patients are common. Most cancer treatments are administered in the outpatient setting, and patients with complications often visit the emergency department. However, there is no recent emergency medicine literature review focusing on genitourinary emergencies in the oncologic population. Objective of the review. To increase awareness of common genitourinary emergencies in patients with cancer and enable the prompt recognition and appropriate management of these conditions. Discussion. Genitourinary emergencies in patients with cancer require a multidisciplinary approach to treatment. The most common genitourinary emergencies in patients with cancer are related to infection, obstructive uropathy, hemorrhagic cystitis, and complications associated with urinary diversions. The treatment approach in patients with infections, including viral infections, is similar to those without cancer. Understanding the changes in the anatomy of patients with urinary diversions or fistulas can help with the management of genitourinary emergencies.

Conclusions

Familiarization with the uniqueness of genitourinary emergencies in patients with cancer is important for emergency physicians.

Late Gastrointestinal Tolerance After Prostate Radiotherapy: Is the Anal Canal the Culprit? A Narrative Critical Review

Introduction

Late gastro-intestinal toxicities (LGIT) secondary to pelvic radiotherapy (RT) are well described in the literature. LGIT are mainly related to rectal or ano-rectal irradiation; however, involvement of the anal canal (AC) in the occurrence of LGIT remains poorly described and understood.

Materials and Methods

The aim of this work was to explore the potential role of the AC in the development of LGIT after prostate irradiation and identify predictive factors that could be optimized in order to limit these toxicities. This narrative literature review was realized using the Pubmed database. We identified original articles published between June 1997 and July 2019, relating to LGIT after RT for localized prostate cancer and for which AC was identified independently. Articles defining the AC as part of an anorectal or rectal volume only were excluded.

Results

A history of abdominal surgery or cardio-vascular risk, anticoagulant or tobacco use, and the occurrence of acute GIT during RT increases the risk of LGIT. A dose-effect relationship was identified between dose to the AC and development of LGIT. Identification and contouring of the AC and adjacent anatomical structures (muscles or nerves) are justified to apply specific dose constraints. As a limitation, our review mainly considered on 3DCRT which is no longer the standard of care nowadays; we did not identify any reports in the literature using moderately hypofractionated RT for the prostate and AC specific dosimetry.

Conclusion

These results suggest that the AC may have an important role in the development of LGIT after pelvic RT for prostate cancer. The individualization of the AC during planning should be recommended in prospective studies.

Personalized Radiation Attenuating Materials for Gastrointestinal Mucosal Protection

Cancer patients undergoing therapeutic radiation routinely develop injury of the adjacent gastrointestinal (GI) tract mucosa due to treatment. To reduce radiation dose to critical GI structures including the rectum and oral mucosa, 3D-printed GI radioprotective devices composed of high-Z materials are generated from patient CT scans. In a radiation proctitis rat model, a significant reduction in crypt injury is demonstrated with the device compared to without (p < 0.0087). Optimal device placement for radiation attenuation is further confirmed in a swine model. Dosimetric modeling in oral cavity cancer patients demonstrates a 30% radiation dose reduction to the normal buccal mucosa and a 15.2% dose reduction in the rectum for prostate cancer patients with the radioprotectant material in place compared to without. Finally, it is found that the rectal radioprotectant device is more cost-effective compared to a hydrogel rectal spacer. Taken together, these data suggest that personalized radioprotectant devices may be used to reduce GI tissue injury in cancer patients undergoing therapeutic radiation.

Clinical Outcomes of a Combined Robotic, Transabdominal, and Open Transperineal Approach for Anastomotic Posterior Urethroplasty

Background: Robotic pelvic surgery is being increasingly utilized for reconstruction proximal to the genitourinary diaphragm. We describe a combined robotic, transabdominal, and open transperineal approach for complex anastomotic posterior urethroplasty. Materials and Methods: We performed a multi-institutional retrospective study of patients who underwent anastomotic posterior urethroplasty by a combined robotic, transabdominal, and open transperineal approach between January 2012 and December 2018. Patient demographics; preoperative, intraoperative, and postoperative clinical data; and complications were reviewed. Urethroplasty success, de novo stress urinary incontinence (SUI), and de novo erectile dysfunction (ED) were evaluated. Results: Twelve patients were identified with a mean follow-up of 596 (range 73-1618) days. Mean patient age was 65.9 (range 53.4-76.8). Reconstruction required corporal splitting, prostatectomy, and gracilis muscle flap use in one (8.3%), eight (66.7%), and four (33.3%) patients, respectively. Postoperative urinary leak, thromboembolic event, and wound abscess occurred in one (8.3%), one (8.3%), and two (16.7%) patients, respectively. Stenosis recurrence occurred in two patients (16.7%) at a mean 187.5 (20-355) postoperative days. De novo ED and de novo SUI were reported in two (16.7%) and four (33.3%) patients, respectively. Nine patients (75.0%) underwent placement of an artificial urinary sphincter at a mean interval of 359.2 (111-1456) days after the index procedure, with no subsequent erosion. Conclusions: Complex posterior urethroplasty by a combined robotic, transabdominal and open transperineal approach is associated with success and complications rates that are comparable to open techniques and may allow for adjunctive procedures such as prostatectomy. This technique allows for the reconstruction of posterior urethral stenoses that would otherwise have been managed conservatively or with urinary diversion.

Magnetic resonance imaging-guided stereotactic body radiotherapy for prostate cancer (mirage): a phase iii randomized trial

Background

Stereotactic body radiotherapy (SBRT) is becoming increasingly used in treating localized prostate cancer (PCa), with evidence showing similar toxicity and efficacy profiles when compared with longer courses of definitive radiation. Magnetic resonance imaging (MRI)-guided radiotherapy has multiple potential advantages over standard computed tomography (CT)-guided radiotherapy, including enhanced prostate visualization (abrogating the need for fiducials and MRI fusion), enhanced identification of the urethra, the ability to track the prostate in real-time, and the capacity to perform online adaptive planning. However, it is unknown whether these potential advantages translate into improved outcomes. This phase III randomized superiority trial is designed to prospectively evaluate whether toxicity is lower after MRI-guided versus CT-guided SBRT.

Methods

Three hundred men with localized PCa will be randomized in a 1:1 ratio to SBRT using CT or MRI guidance. Randomization will be stratified by baseline International Prostate Symptom Score (IPSS) (≤15 or > 15) and prostate gland volume (≤50 cc or > 50 cc). Five fractions of 8 Gy will be delivered to the prostate over the course of fourteen days, with or without hormonal therapy and elective nodal radiotherapy (to a dose of 5 Gy per fraction) as per the investigator’s discretion. The primary endpoint is the incidence of physician-reported acute grade ≥ 2 genitourinary (GU) toxicity (during the first 90 days after SBRT), as assessed by the CTCAE version 4.03 scale. Secondary clinical endpoints include incidence of acute grade ≥ 2 gastrointestinal (GI) toxicity, 5-year cumulative incidences of physician-reported late grade ≥ 2 GU and GI toxicity, temporal changes in patient-reported quality of life (QOL) outcomes, 5-year biochemical recurrence-free survival and the proportion of fractions of MRI-guided SBRT in which online adaptive radiotherapy is used.

Discussion

The MIRAGE trial is the first randomized trial comparing MRI-guided with standard CT-guided SBRT for localized PCa. The primary hypothesis is that MRI-guided SBRT will lead to an improvement in the cumulative incidence of acute grade ≥ 2 GU toxicity when compared to CT-guided SBRT. The pragmatic superiority design focused on an acute toxicity endpoint will allow an early comparison of the two technologies.

Trial registration

Clinicaltrials.gov identifier: NCT04384770. Date of registration: May 12, 2020.

https://clinicaltrials.gov/ct2/show/NCT04384770

Protocol version

Version 2.1, Aug 28, 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08281-x.

Retrospective assessment of radiation toxicity from a definitive-intent, moderately hypofractionated image-guided intensity-modulated protocol for anal sac adenocarcinoma in dogs

A recent calculation study predicted acceptable toxicity in pelvic organs at risk for a new definitive-intent, moderately hypofractionated radiation therapy (RT) protocol (12 x 3.8 Gy), when used with image-guided intensity-modulated radiation therapy (IG-IMRT). We hypothesized this protocol to result in clinically acceptable radiation toxicities. Dogs diagnosed with and irradiated for anal sac adenocarcinoma (ASAC) were retrospectively assessed. Eleven dogs were included, six had prior surgery. Before any therapy, staging according to Polton et al. resulted in the following distribution: stage 1 (n = 1), stage 2 (n = 1), stage 3a (n = 6), stage 3b (n = 3). We scored radiation toxicities at the end of therapy, at weeks 1, 3 and every 3 months after RT according to Veterinary Radiation Therapy Oncology Group radiation toxicity criteria. Clinical follow-up was maintained on regular intervals combined with computed tomography (n = 3). Median follow-up time for dogs still alive was 594 days (range: 224-972 days). Within 1 week post treatment, eight dogs (73%) developed grade 2 and four dogs (36%) grade 1 acute toxicity in the perianal region. All acute toxicities resolved or improved to grade 1 within 3 weeks after treatment. Late toxicity, for example, chronic colitis/diarrhoea, ulcerations, strictures or myelopathies was not observed in any patient. Five dogs were euthanized 105, 196, 401, 508 and 908 days after RT and six dogs were still alive, one in spite of progressive disease. The median progression-free survival was 908 days (95%CI: 215; 1602). The previous theoretically described definitive-intent, moderately hypofractionated protocol using IG-IMRT for the treatment of advanced ASAC showed clinically acceptable acute and late toxicities.

Robot-assisted Cystectomy with Intracorporeal Urinary Diversion After Pelvic Irradiation for Prostate Cancer: Technique and Results from a Single High-volume Center

BACKGROUND

Radiation therapy (RT) for prostate cancer (PCa) treatment is burdened by high rates of late urinary adverse events (UAEs). The feasibility of robot-assisted cystectomy (RAC) with intracorporeal urinary diversion (ICUD) for treatment of high-grade UAEs has never been assessed.

OBJECTIVE

To report perioperative outcomes, early (≤90 d) and late (>90 d) complications among patients undergoing RAC for UAEs after RT.

DESIGN, SETTING, AND PARTICIPANTS

We retrospectively evaluated 32 patients undergoing RAC with ICUD for UAEs in a single tertiary centre.

SURGICAL PROCEDURE

Surgery was performed using a da Vinci Xi system with adaptation for the primary treatment.

MEASUREMENTS

Perioperative outcomes included estimated blood loss (EBL), operative time (OT), intraoperative complications, and length of stay (LOS). Data for early and late postoperative complications were collected using the quality criteria recommended by the European Association of Urology. Univariate logistic regressions were performed to test the effect of baseline and perioperative characteristics on early postoperative complications.

RESULTS AND LIMITATIONS

The median age-adjusted Charlson comorbidity index (ACCI) was 6 (IQR 5-7). The indication for RAC was hemorrhagic radiation cystitis in 29 cases (91%), contracted bladder in two cases (6.2%), and urinary fistula in one case (3.1%). The median EBL, OT, and LOS were 250 ml, 330 min, and 10 d, respectively. A total of 31 (97%) patients received an ileal conduit. The 90-d rate of Clavien-Dindo grade ≥IIIa complications was 28%. The late complication rate was 46% and the perioperative mortality rate was 0%. On univariate analyses, ACCI was the only parameter correlated with the risk of early complications (odds ratio 1.75, 95% confidence interval 1.05-2.9; p =  0.03). The median follow-up was 30 mo (IQR 15-40). The lack of comparison with open cystectomy represents the main limitation.

CONCLUSIONS

RAC for UAEs in patients with a history of pelvic irradiation is a feasible option in high-volume centers. The use of new technologies can help to overcome some of the technical difficulties and reduce the risk of perioperative and late complications.

PATIENT SUMMARY

We report our experience with robot-assisted surgery for removal of the bladder in the management of urinary problems after radiation therapy for prostate cancer. When performed by highly experienced surgeons, this is a feasible procedure with outcomes and early and late complication rates that are acceptable.

Palliative local treatment of bone metastases by 125I seed brachytherapy under DynaCT guidance: single-center experience

PURPOSE

We aimed to evaluate the clinical benefit of 125I seed brachytherapy under DynaCT guidance for palliative local treatment of bone metastases.

METHODS

From December 2014 to September 2017, 82 patients with painful bone metastases, who experienced treatment failure using standard strategies or rejected treatment were enrolled in this retrospective study. All patients underwent 125I seed brachytherapy under DynaCT guidance. Technical success, visual analogue scale (VAS), numerical rating scale (NRS), verbal rating scale (VRS), Karnofsky performance status (KPS) and complications were analyzed.

RESULTS

The success rate of 125I seed implantation was 100%. The VAS and NRS scores for the most severe pain were 7.0 (5.0-9.0) and 8.0 (6.0-9.0) before brachytherapy. The pain scores assessed every 2 hours gradually decreased within 12 hours (p < 0.001). A comparison of KPS scores showed that patients had significantly better quality of life on weeks 1, 4, and 8 than on week 0 (p < 0.001). The associated complications were mild subcutaneous hemorrhage 25.6% (21/82), fever 7.3% (6/82), minor displacement of radioactive seeds 5.0% (4/82), pathologic fracture 2.4% (2/82), and local skin reaction 2.4% (2/82). After symptomatic treatment, all complications were relieved. Minor displacement of radioactive seeds did not cause damage to adjacent tissues. No serious life-threatening complications occurred in the study group.

CONCLUSION

DynaCT-guided 125I seed implantation is a safe and effective method for palliation of painful bone metastases from cancer after failure or rejection of conventional treatments.

Biological impact of dosimetric perturbations of a fiducial marker and the daily number of fields in proton therapy for prostate cancer

The purpose of this study was to estimate the biological impact of dosimetric perturbations of a fiducial marker and the daily number of fields in proton therapy for prostate cancer. Using a linear-quadratic model, normalized total doses (NTDs) of points where deposited dose was reduced from the prescribed dose by dosimetric perturbation of a fiducial marker were calculated in two hypothetical prostate cancer treatment schedules: a) irradiation of both parallel-opposed lateral fields and b) irradiation of alternate field in each daily treatment. The impact of hypofractionation and sublethal damage repair between irradiation on NTD was also estimated. The NTD of two fields/day schedule becomes lower than that of one field/day schedule. The difference becomes larger as dose reduction from one of two fields becomes more enhanced. The NTD reduction from the total dose in the two fields/day schedule is largest (30% of total dose) where the dose from one beam is completely lost by a fiducial marker. In contrast, the NTD reduction from the total dose in the one field/day schedule is largest (9% of total dose) where the half dose from one beam is decreased by a fiducial marker. In addition, the NTD reduction becomes larger as the fractional dose increases in a hypofractionated regimen, and when the effect of sublethal damage repair was incorporated. These influences become significant in prostate cancer since the radiobiological sensitivity α/β of prostate cancer is lower than other cancer types and normal tissues late complication. Treating with one alternate field in a daily treatment can improve a deteriorating treatment effect by dosimetric distortion of a fiducial marker in prostate cancer treatment. However, the choice of the number of beams in a fraction must also be determined by considering the sparing of normal tissues and patient-specific status.

Impact of radical prostatectomy on bladder function as demonstrated on urodynamics study-A systematic review

AIMS

This study aims to describe the effects of radical prostatectomy (RP) on bladder function by performing a systematic review of urodynamics study findings before and after RP.

METHODS

This systematic review was conducted in accordance with the PRISMA guideline and registered on PROSPERO (CRD42020206844). A systematic search was conducted using PubMed, Cochrane, and Embase. Studies were included if they involved men who underwent RP and had urodynamics study performed preoperatively, postoperatively, or both. Studies that included only subgroups of patients based on symptoms were excluded. Three hundred and four articles were screened, with 20 articles included. A qualitative analysis was performed.

RESULTS

The rate of baseline bladder outlet obstruction (BOO) pre-RP was 19%-67%. All six studies with comparative data pre- and postoperatively demonstrated a decrease in the rate of patients with equivocal or clear obstruction. The baseline rates of detrusor overactivity (DO) varied widely from 11% to 61.2%. Six of eight studies with 6 months or more follow-up showed an improvement in the rates of DO ranging from 3.0% to 12.5%. The rate of de novo DO ranged from 0% to 54.5%. Four studies reported an increased rate of impaired bladder contractility and two of three studies showed a worsening rate of impaired bladder compliance following RP. This review is limited by the absence of level I/II studies.

CONCLUSIONS

Urodynamics study shows that BOO is improved following RP in most patients. RP resolves DO in some patients and cause de novo DO in others. The net effect is a reduced overall rate of DO in most studies. Bladder compliance and contractility may be impaired after RP.

Sexual function and rehabilitation after radiation therapy for prostate cancer: a review

The treatment of prostate cancer is partly guided by patient preferences. Radical prostatectomy and radiation therapy are the standard radical therapies for localized disease and render comparable oncologic outcomes. Considering that survival is high regardless of the chosen treatment, factors such as treatment-related toxicities affecting the patients' quality of life play an important role in their decision. Notably, post-treatment sexual dysfunction, which includes decreased libido, erectile dysfunction, and ejaculatory dysfunction has been shown to be an important and prevalent concern of prostate cancer survivors. In this literature review, we sought to characterize the sexual complications associated with radiation therapy and map the available sexual rehabilitation options for prostate cancer survivors experiencing sexual dysfunction as a result of radiation therapy. We identified medical, non-biomedical, counseling, and lifestyle modification options for prostate cancer survivors seeking sexual rehabilitation. Future research in this area should address the standardization of sexual side-effect reporting and investigate sexual outcomes and rehabilitation in more diverse groups and of transgender and nonheterosexual prostate cancer survivors.

Metformin as a radiosensitiser for pelvic malignancy: A systematic review of the literature

BACKGROUND

The treatment of pelvic malignancies has continued to improve over recent years, with neoadjuvant radiotherapy often considered the gold standard to downstage disease. Radiosensitisers are routinely employed in an attempt to improve response of cancers to radiotherapy. Previous preclinical evidence has suggested a role for metformin, a commonly used drug for type 2 diabetes.

METHOD

A literature search was performed for published full text articles using the PubMed, Cochrane and Scopus databases using the search criteria string 'Metformin' AND ('Radiosensitivity' OR 'radiosensitising' OR 'radiosensitising'). Additional papers were detected by scanning the references of relevant papers. Data were extracted from each study by two authors onto a dedicated proforma. The review was registered on the PROSPERO database (ID: CRD42020199066).

RESULTS

A total of 242 papers were identified, 11 of which were included in this review; an additional 5 papers were obtained from reference searches. Metformin has been demonstrated to reduce cell-viability post-radiotherapy in both rectal and prostate cancer cell lines, with an enhanced effect in tumours with a p53 mutation and increased apoptosis post-radiotherapy for cervical cancer. Clinical trials demonstrate improved tumour and nodal downstaging and pCR rates for rectal cancer using metformin as a radiosensitiser.

CONCLUSION

With an increasing understanding of the underlying mechanism of the effects on metformin prospective studies are required to assess the effect of routine use on cancer related outcomes. Progressive future studies may be better served by the use of predictive biomarker guided treatment to enable identification of the appropriate cohort to target.

[Pelvic irradiation and hematopoietic toxicity: A review of the literature]

Pelvic bone marrow is the site of nearly 50% of total hematopoiesis. Radiation therapy of pelvic lymph node areas, and cancers located near the bony structures of the pelvis, exposes to hematological toxicity in the range of 30 to 70%. This toxicity depends on many factors, including the presence or absence of concomitant chemotherapy and its type, the volume of irradiated bone, the received doses, or the initial hematopoietic reserve. Intensity modulated radiation therapy allows the optimisation of dose deposit on at risk organs while providing optimal coverage of target volumes. However, this suggests that dose constraints should be known precisely to limit the incidence of radiation side effects. This literature review focuses firstly on pelvic lymph node areas and bony volumes nearby, then on the effects of irradiation on bone marrow and the current dosimetric constraints resulting from it, and finally on hematological toxicities by carcinologic location and progress in reducing these toxicities.

Early Results of Unilateral Prostatic Artery Embolization as a Focal Therapy in Patients with Prostate Cancer under Active Surveillance: Cancer Prostate Embolisation, a Pilot Study

PURPOSE

To evaluate the feasibility of prostatic artery embolization in patients with low-risk prostate cancer (PC) under active surveillance (AS).

METHODS

This monocentric prospective pilot study, running from June 2018 to June 2019, included 10 patients with low-risk PC under AS, median age 72 years (range, 62-77 years), with a unilateral focal lesion visible on magnetic resonance (MR) imaging, with Prostate Imaging Reporting and Data System v2 score ≥3/5 confirmed by multiparametric MR imaging-targeted biopsy and Gleason score 6. The patients underwent unilateral prostatic artery embolization with 300-500 μm Embospheres in the affected prostatic lobe. The primary endpoint was technical feasibility (prostate and no off-target ischemia in the imaging). The secondary endpoints included safety, negative biopsies/MR imaging response/functional outcomes at 6 months, and oncologic efficacy at 1 year.

RESULTS

Embolization was successfully achieved in all patients; prostate ischemia was confirmed on multiparametric MR imaging, and no off-target ischemia was reported. No major complications were reported. Four patients (40%) presented with both negative targeted and systematic biopsies at 6 months. No lesions were seen on the MR imaging in 30% of patients. The mean International Prostate Symptom Score and International Index of Erectile Function score were 7 and 19 and 5 and 20 at baseline and 6 months, respectively, with no significant difference. Nine patients (90%) were still under AS at 1 year. One patient (10%) had PC progression outside the target lesion and was switched over to curative radiotherapy.

CONCLUSIONS

Prostatic artery embolization is feasible and appears safe for prostate cancer patients under AS, with no impact on erectile function or continence status. These results justify the pursuit of further studies.

Apical periurethral transition zone lesions: MRI and histology findings

PURPOSE

Apical periurethral transition zone (TZ) cancers can pose unique problems for surgery and radiation therapy. Here, we describe the appearance of such cancers on multiparametric MRI (mpMRI) and correlate this with histopathology derived from MRI-targeted biopsy.

MATERIALS AND METHODS

Between May 2011 and January 2019, a total of 4381 consecutive patients underwent 3 T mpMRI. Of these, 53 patients with 58 apical periurethral TZ lesions underwent TRUS/MRI fusion-guided biopsy and 12-core systematic TRUS-guided biopsy. Correlation was made with patient age, PSA, PSA density, whole prostate volume, and Gleason scores.

RESULTS

A total 53 men (median age 68 years, median PSA 7.94 ng/ml) were identified as having at least one apical periurethral TZ lesion on mpMRI and 5 (9%) patients had more than one apical periurethral lesion. Thus, 58 lesions were identified in 53 patients. Of these 37/53 patients (69%) and 40/58 lesions were positive at biopsy for prostate cancer. Seven were diagnosed by 12-core systematic TRUS-guided biopsy and 34 were diagnosed by TRUS/MRI fusion-guided biopsy. Gleason score was ≥ 3 + 4 in 34/58 (58%) lesions.

CONCLUSION

Identification of apical periurethral TZ prostate cancers is important to help guide surgical and radiation therapy as these tumors are adjacent to critical structures. Because of the tendency to undersample the periurethral zone during TRUS biopsy, MRI-guided biopsy is particularly helpful for detecting apical periurethral TZ prostate cancers many of which prove to be clinically significant.

Long-Term Risk of Hip Complications After Radiation Therapy for Prostate Cancer: A Dose-Response Study

Purpose

The aim of the present study was to analyze the long-term incidence of hip complications after external beam radiation therapy compared with age-matched controls from the general population. We also investigated whether there were any dose-response associations.

Methods and materials

A total of 349 patients with prostate cancer treated to curative dose with external beam radiation therapy between 1997 and 2002 were included in the study. Physical and fractionation-corrected dose-volume descriptors were derived for the femoral heads, pubic bone, and sacrum. Information on skeletal events was collected for the patients and 1661 matched controls through the Prostate Cancer database Sweden. Uni- and multivariable Cox proportional hazard regressions were used to analyze the time to event.

Results

Data from 346 patients were available for analysis. The median mean physical dose and corresponding equivalent 2-Gy/fraction dose (EQD2) to the femoral heads were 35.5 Gy and 28.7 Gy, respectively. The median follow-up time was 16.0 years. During the follow up, 12 hip fractures occurred. Hip osteoarthritis was diagnosed in 36 cases, with 29 cases leading to replacement surgery. No increased risk of hip fractures was found. Hip osteoarthritis was the only event for which a statistically significant difference was found between the irradiated cohort and the controls (cause-specific hazard ratio: 1.56; 95% confidence interval, 1.07-2.26; P = .02). The cumulative incidence of osteoarthritis at 10 years was 8.1% and 4.9% in the irradiated cohort and the controls, respectively. A significant relationship between osteoarthritis and the volume of the femoral head receiving ≥40 Gy (ie, EQD2) was found.

Conclusions

In this study of 346 patients treated with conventional radiation therapy, we found no increased risk of hip fracture but an increased risk of clinically relevant osteoarthritis at long-term follow up. Our results indicate a dose-response relationship between osteoarthritis and the volume of the femoral head receiving an EQD2 dose of ≥40 Gy.

Impacts of combining anti-PD-L1 immunotherapy and radiotherapy on the tumour immune microenvironment in a murine prostate cancer model

BACKGROUND

Radiotherapy enhances innate and adaptive anti-tumour immunity. It is unclear whether this effect may be harnessed by combining immunotherapy with radiotherapy fractions used to treat prostate cancer. We investigated tumour immune microenvironment responses of pre-clinical prostate cancer models to radiotherapy. Having defined this landscape, we tested whether radiotherapy-induced tumour growth delay could be enhanced with anti-PD-L1.

METHODS

Hypofractionated radiotherapy was delivered to TRAMP-C1 and MyC-CaP flank allografts. Tumour growth delay, tumour immune microenvironment flow-cytometry, and immune gene expression were analysed. TRAMP-C1 allografts were then treated with 3 × 5 Gy ± anti-PD-L1.

RESULTS

3 × 5 Gy caused tumour growth delay in TRAMP-C1 and MyC-CaP. Tumour immune microenvironment changes in TRAMP-C1 at 7 days post-radiotherapy included increased tumour-associated macrophages and dendritic cells and upregulation of PD-1/PD-L1, CD8+ T-cell, dendritic cell, and regulatory T-cell genes. At tumour regrowth post-3 × 5 Gy the tumour immune microenvironment flow-cytometry was similar to control tumours, however CD8+, natural killer and dendritic cell gene transcripts were reduced. PD-L1 inhibition plus 3 × 5 Gy in TRAMP-C1 did not enhance tumour growth delay versus monotherapy.

CONCLUSION

3 × 5 Gy hypofractionated radiotherapy can result in tumour growth delay and immune cell changes in allograft prostate cancer models. Adjuncts beyond immunomodulation may be necessary to improve the radiotherapy-induced anti-tumour response.

Gastrointestinal consequences of cancer treatment: evaluation of 10 years' experience at a tertiary UK centre

OBJECTIVE

Up to 90% of patients treated for pelvic cancers experience chronic gastrointestinal (GI) symptoms. This study characterises this patient cohort at a single centre, addressing a paucity of publications reporting 'real-world' experiences.

METHOD

Outpatient referrals, from oncology to the gastroenterology and nutrition services, at a tertiary London hospital from 2006 to 2016, were retrospectively identified. Patient characteristics, reported symptoms, investigations, diagnoses, response to therapeutics and follow-up were recorded.

RESULTS

Of 269 patients referred, 81% were within the latter 5 years. A total of 260 patients had diagnoses of pelvic cancers (prostatic (52%), cervical (19%) and endometrial (19%)). Among 247 treated with radiotherapy, the median time from radiotherapy to symptom onset was 8 months. Common symptoms were rectal bleeding (51%), diarrhoea (32%), faecal urgency (19%) and pain (19%). Patients underwent a median of three investigations including lower GI endoscopy (86%), thyroid function tests (33%) and glucose hydrogen breath test (30%). Diagnoses included radiation proctopathy (39%), colonic polyps (16%), pelvic floor dysfunction (12%), bile acid malabsorption (BAM) (8%), small intestinal bacterial overgrowth (SIBO) (8%), vitamin D deficiency (7%) and iron deficiency (7%). Among 164 discharged patients, the time to discharge was 7 months, after a median of two appointments.

CONCLUSIONS

This unique patient group reports a complex mix of symptoms and requires specialist review and consideration of often uninvestigated diagnoses (pelvic dysfunction, BAM, SIBO and nutritional deficiencies). Such patients are often overlooked, compared with those suffering many other chronic GI disorders. Further reports from non-dedicated centres treating patients with pelvic radiation disease will aid in understanding of secondary GI diagnoses and variation in practice.

A-blockers for the management of lower urinary tract symptoms in patients with prostate cancer treated with external beam radiotherapy: a randomized controlled study

BACKGROUND

This is a prospective study aiming to assess the efficacy of α-blockers in treating radiotherapy-induced symptoms of the lower urinary tract and its possible prophylactic role on acute urinary retention (AUR) in patients undergoing radical external beam radiotherapy (EBRT) for localized prostate cancer (PCa).

METHODS

Overall, 108 patients with localized PCa were recruited and randomly assigned in to two groups; 54 patients of Group 1 received tamsulosin 0.4 mg once daily with the initiation of EBRT and for 6 months and 54 patients of Group 2 served as the control group. All patients received radical EBRT and had post-void volume (Vres) assessment. The International Prostate Symptom Score (IPSS) questionnaire and evaluation of episodes of AUR were performed after the end of radiotherapy, at 3 and at 6 months.

RESULTS

The incidence of AUR was significantly (p = 0.027) lower in group 1 compared to group 2. No independent predictive factors for AUR were identified in regression analysis. The IPSS changes in univariate and multivariate analysis at 3 months showed significant correlation with α-blockers only, while at 6 months showed significant correlation with Vres assessments (at 3 and 6 months) and with α-blockers. Side effects due to medication were mild and none of the patients discontinued the treatment.

CONCLUSIONS

The selective use of α-blocker appears to prevent AUR in EBRT-treated patients. Although the administration of α-blockers might relieve patient-reported symptoms, there are no established independent predictive factors to distinguish patients who may benefit.

Long-Term Results of Moderate Hypofractionation to Prostate and Pelvic Nodes Plus Androgen Suppression in High-Risk Prostate Cancer

PURPOSE

Moderate hypofractionated radiation therapy (HypoRT) is an attractive alternative to conventionally fractionated radiation therapy for prostate cancer. However, most studies using HypoRT only included the prostate as the target volume. We report long-term outcomes of patients with high-risk prostate cancer treated with androgen deprivation therapy (ADT) and HypoRT to the prostate and nodal areas with a simultaneous integrated boost technique.

METHODS AND MATERIALS

Patients with localized, high-risk prostate cancer entered a prospective phase I/II study with a HypoRT regimen of 60 Gy/20 fractions (4 weeks) to the prostate volume while the nodal areas received 44 Gy in the same 20 fractions delivered with intensity modulated radiation therapy with a simultaneous integrated boost technique. ADT started 2 to 3 months before HypoRT. Toxicity was prospectively assessed according to the Common Terminology Criteria for Adverse Events v3. Outcomes rates were calculated by the actuarial method of Kaplan-Meier from the date of last radiation treatment until date of event.

RESULTS

We report on the first 105 patients treated between October 2010 and February 2014. Median follow-up was 74 months, with 97% of patients followed for more than 36 months. Median ADT duration was 18 months. The worst grade 2 or higher late gastrointestinal or genitourinary toxicity was seen in 7% and 9%, respectively. There was no grade 4 or 5 toxicity. At the last follow-up, the rates of grade ≥2 gastrointestinal or genitourinary toxicity were 2% and 3%, respectively, with no residual grade ≥3 toxicity. The 5- and 7-year actuarial overall survival and relapse free survival were 91% and 85% and 87% and 81%, respectively.

CONCLUSIONS

The longest follow-up report of moderate HypoRT (plus ADT) to the prostate and pelvic nodes shows that this approach is feasible, well tolerated, and effective. It is convenient for patients and the health system. A larger randomized trial using this approach is warranted.

The scope, presentation, and management of genitourinary complications in patients presenting with high-grade urethral complications after radiotherapy for prostate cancer

INTRODUCTION

The scope of complications arising after radiotherapy (RT) treatment for prostate cancer is under-recognized and not well-described. The objective of this study is to describe the presentation, scope, and management of genitourinary (GU) complications in patients referred for high-grade urethral complications or sphincter weakness incontinence after prostate RT.

METHODS

A retrospective review was performed of patients referred to a reconstructive urologist for management of grade 4 urethral complications and sphincter weakness incontinence after prostate RT from December 2004 to December 2015. Patients' signs, symptoms, complications, and treatments are described.

RESULTS

A total of 120 patients were identified, with a mean age of 67.8 years; 55.8% (n=67) received external beam radiotherapy (EBRT), 38.3% (n=46) brachytherapy (BT), and 5.8% (n=7) combination RT. The mean time to first complication after RT was 57.7 months (1-219) and number of complications per patient was 5.1±2.2. The most common associated complications were urethral stenosis (n=106, 88.3%), sphincter weakness urinary incontinence (n=55, 45.8%), radiation cystitis (n=61, 50.8%), refractory storage lower urinary tract symptoms (n=106, 88.3%), GU pain (n=28, 23.3%), and prostate necrosis/abscess (n=17, 14.2%). Patients required a mean of 7.4±4.4 treatments over a 33-month period, including urethral dilation/urethrotomy (n= 93, 77.5%), urethroplasty (n=53, 44.2%), transurethral resection (n=52, 43.3%), cystolithopaxy (n=14, 11.7%), artificial urinary sphincter (n=8, 6.7%), and urinary diversion (n=8, 6.7%). Patients with RT combined with other modalities had more complications (6.2 vs. 4.2, p=0.001), higher rates of incontinence (93.8% vs. 29.5%, p=0.001), necrosis (31.3% vs. 8.0%, p=0.003), erectile dysfunction (84.4% vs. 51.1%, p=0.001), and hematuria (59.4% vs. 36.4%, p=0.04).

CONCLUSIONS

Urethral complications related to prostate RT are seldom an isolated problem and require a substantial amount of urological resources and interventions.

Proof-of-principle Phase I results of combining nivolumab with brachytherapy and external beam radiation therapy for Grade Group 5 prostate cancer: safety, feasibility, and exploratory analysis

BACKGROUND

To determine whether combining brachytherapy with immunotherapy is safe in prostate cancer (PCa) and provides synergistic effects, we performed a Phase I/II trial on the feasibility, safety, and benefit of concurrent delivery of anti-PD-1 (nivolumab) with high-dose-rate (HDR) brachytherapy and androgen deprivation therapy (ADT) in patients with Grade Group 5 (GG5) PCa.

METHODS

Eligible patients were aged 18 years or older with diagnosis of GG5 PCa. Patients received ADT, nivolumab every two weeks for four cycles, with two cycles prior to first HDR, and two more cycles prior to second HDR, followed by external beam radiotherapy. The primary endpoint was to determine safety and feasibility. This Phase I/II trial is registered with ClinicalTrials.gov (NCT03543189).

RESULTS

Between September 2018 and June 2019, six patients were enrolled for the Phase I safety lead-in with a minimum observation period of 3 months after nivolumab administration. Overall, nivolumab was well tolerated in combination with ADT and HDR treatment. One patient experienced a grade 3 dose-limiting toxicity (elevated Alanine aminotransferase and Aspartate aminotransferase) after the second cycle of nivolumab. Three patients (50%) demonstrated early response with no residual tumor detected in ≥4 of 6 cores on biopsy post-nivolumab (4 cycles) and 1-month post-HDR. Increase in CD8+ and FOXP3+/CD4+ T cells in tissues, and CD4+ effector T cells in peripheral blood were observed in early responders.

CONCLUSION

Combination of nivolumab with ADT and HDR is well tolerated and associated with evidence of increased immune infiltration and antitumor activity.

Patterns of treatment failure in patients with prostate cancer treated with 76-80 Gy radiotherapy to the prostate and seminal vesicles ± hormonotherapy

PURPOSE

To assess the pattern of treatment failure in patients with prostate cancer (PCa) treated with radiotherapy (76-80 Gy) ± hormone therapy (HT). We also evaluated the influence of treatment failure on survival outcomes.

METHODS

Retrospective study of patients with PCa (n = 302) treated with radiotherapy (RT) ± HT at our centre between November 1999 and July 2007. The mean patient age was 70.2 years (range 51-87). Distribution by NCCN risk group was low (n = 80, 26.5%), intermediate (n = 86, 28.5%), high (n = 77, 25.5%), and very high (n = 49, 16.2%). Most patients (n = 273, 90.4%) received IMRT at a dose of 76-80 Gy. HT was administered in 237 patients (78.5%), in most cases (n = 167, 55.3%) for < 7 months RESULTS: Survival rates at 10 years were: overall survival (OS), 64.3%; biochemical disease-free survival, 83.9%; disease-free survival, 92.5%; and metastasis-free survival (MFS), 94.3%. Biochemical failure (BF) was observed in 55 cases (18.2%), 32 of whom subsequently developed clinical recurrence: metastasis (n = 17, 5.6%), local failure (n = 11, 3.6%), and regional failure (n = 4, 1.3%). The cause of death (n = 159) was intercurrent disease in 115 cases (72.3%), second cancer in 27 (17.0%), and PCa in 17 (10.7%). Biochemical failure-free survival ≤ 24 months was significantly associated with worse OS and MFS (p = 0.0001). Late genitourinary and gastrointestinal toxicity grade ≥ 3 (RTOG) was observed in 18 (6.0%) and 7 (2.3%) patients, respectively.

CONCLUSIONS

The main type of treatment failure after 76-80 Gy of radiotherapy ± HT is local or metastatic. In all cases, biochemical failure occurred prior to treatment failure. BF within 24 months of treatment completion was significantly associated with worse OS and MFS.

Dosimetric evaluation of whole-pelvis radiation therapy of prostate cancers: clinical experience

Background:

The standard treatment modalities for prostate cancer include surgery, chemotherapy, hormonal therapy and radiation therapy or any combination depending on the stage of the tumour. Radiation therapy is a common and effective treatment modality for low-intermediate-risk patients with localised prostate cancer, to treat the intact prostate and seminal vesicles or prostate bed post prostatectomy. However, for high-risk patients with lymph node involvement, treatment with radiation will usually include treatment of the whole pelvis to cover the prostate and seminal vesicles or prostate bed and the pelvic lymph nodes followed by a boost delivery dose to the prostate and seminal vesicles or prostate bed.

Materials and Methods:

We retrospectively analysed the treatment plans for 179 prostate cancer patients treated at the cancer centre with the volumetric-modulated arc therapy (VMAT) technique via RapidArc using 6 MV photon beam. Patients were either treated with a total prescription dose of 78 Gy in 39 fractions for patients with intact prostate or 66 Gy in 33 fractions for post prostatectomy patients.

Results:

There were 114 (64%) patients treated with 78 Gy/39 and 65 (36%) treated with 66 Gy/34. The mean homogeneity index (HI), conformity index (CI) and uniformity index (UI) for the PTV-primary of patients treated with 78 Gy are 0.06 ± 0.01, 1.04 ± 0.01 and 0.99 ± 0.01, respectively, and the corresponding mean values for patients treated with 66 Gy are 0.06 ± 0.02, 1.05 ± 0.01 and 0.99 ± 0.01, respectively. The mean PTV-primary V95%, V100% and V105% are 99.5 ± 0.5%, 78.8 ± 12.2% and 0.1 ± 0.5%, respectively, for patients treated with 78 Gy and 99.3 ± 0.9%, 78.1 ± 10.6% and 0.1 ± 0.4%, respectively, for patients treated with 66 Gy. The rectal V50Gy, V65Gy, V66.6Gy, V70Gy, V75Gy and V80Gy are 26.8 ± 9.1%, 14.2 ± 5.3%, 13.1 ± 5.0%, 10.8 ± 4.3%, 6.9 ± 3.1% and 0.1 ± 0.1%, respectively, for patients treated with 78 Gy and 33.7 ± 8.4%, 14.1 ± 4.5%, 6.7 ± 4.5%, 0.0 ± 0.2%, 0.0% and 0.0%, respectively, for patients treated with 66 Gy.

Conclusion:

The use of VMAT technique for radiation therapy of high-risk prostate cancer patients is an efficient and reliable method for achieving superior dose conformity, uniformity and homogeneity to the PTV and minimal doses to the organs at risk. Results from this study provide the basis for the development and implementation of consistent treatment criteria in radiotherapy programs, have the potential to establish an evaluation process to define a consistent, standardised and transparent treatment path for all patients that reduces significant variations in the acceptability of treatment plans and potentially improve patient standard of care.

Harnessing the potential of multimodal radiotherapy in prostate cancer

Radiotherapy in combination with androgen deprivation therapy (ADT) is a standard treatment option for men with localized and locally advanced prostate cancer. However, emerging clinical evidence suggests that radiotherapy can be incorporated into multimodality therapy regimens beyond ADT, in combinations that include chemotherapy, radiosensitizing agents, immunotherapy and surgery for the treatment of men with localized and locally advanced prostate cancer, and those with oligometastatic disease, in whom the low metastatic burden in particular might be treatable with these combinations. This multimodal approach is increasingly recognized as offering considerable clinical benefit, such as increased antitumour effects and improved survival. Thus, radiotherapy is becoming a key component of multimodal therapy for many stages of prostate cancer, particularly oligometastatic disease.

Cranberry capsules are not superior to placebo capsules in managing acute non-haemorrhagic radiation cystitis in prostate cancer patients: A phase III double blinded randomised placebo controlled clinical trial

PURPOSE

Acute radiation cystitis affects the quality of life of many prostate cancer patients. A previous pilot study suggested that cranberry capsules may decrease some of the symptoms of acute radiation cystitis. Here we further test their effectiveness in a multicentre double blinded placebo-controlled clinical trial.

MATERIAL AND METHODS

A total of 108 prostate cancer patients were recruited at three New Zealand hospitals between September 2016 and January 2019. Out of this cohort, 101 patients provided datasets for analysis (51 men on cranberry capsules and 50 men on beetroot-containing placebo capsules). Patients took two capsules each morning during RT and for 2 weeks after completion of RT. Three measures were used to assess cystitis severity: modified RTOG, O'Leary interstitial cystitis scale and a sensitive novel radiation induced cystitis assessment scale (RICAS). Cystitis severity was scored at baseline and weekly thereafter during RT and for two weeks after completion of RT. Radiation protocols were stratified to conventional fractionation or hypo-fractionated radiation therapy (CHHiP) to the prostate or radiation to the prostate bed.

RESULTS

Cranberry capsules performed significantly worse than placebo capsules with respect to day time frequency and bladder control, using the more sensitive RICAS scale. No significant difference in cystitis severity was seen between patients receiving hypofractionation and those receiving conventional fractionation to the prostate gland.

CONCLUSION

Cranberry capsules were not superior to beetroot-containing placebo capsules in managing radiation cystitis in our prostate patient cohort. RICAS may be a useful tool for measuring radiation cystitis in future studies.

The urethral position may shift due to urethral catheter placement in the treatment planning for prostate radiation therapy

PURPOSE

To determine the best method to contour the planning organ at risk volume (PRV) for the urethra, this study aimed to investigate the displacement of a Foley catheter in the urethra with a soft and thin guide-wire.

METHODS

For each patient, the study used two sets of computed tomography (CT) images for radiation treatment planning (RT-CT): (1) set with a Foley urethral catheter (4.0 mm diameter) plus a guide-wire (0.46 mm diameter) in the first RT-CT and (2) set with a guide-wire alone in the second CT recorded 2 min after the first RT-CT. Using three fiducial markers in the prostate for image fusion, the displacement between the catheter and the guide-wire in the prostatic urethra was calculated. In 155 consecutive patients treated between 2011 and 2017, 5531 slices of RT-CT were evaluated.

RESULTS

Assuming that ≥3.0 mm of difference between the catheter and the guide-wire position was a significant displacement, the urethra with the catheter was displaced significantly from the urethra with the guide-wire alone in > 20% of the RT-CT slices in 23.2% (36/155) of the patients. The number of patients who showed ≥3.0 mm anterior displacement with the catheter in ≥20% RT-CT slices was significantly larger at the superior segment (38/155) than at the middle (14/155) and inferior segments (18/155) of the prostatic urethra (p < 0.0167).

CONCLUSIONS

The urethral position with a Foley catheter is different from the urethral position with a thin and soft guide-wire in a significant proportion of the patients. This should be taken into account for the PRV of the urethra to ensure precise radiotherapy such as in urethra-sparing radiotherapy.