Australian & New Zealand Faculty of Radiation Oncology Genito-Urinary Group: 2011 consensus guidelines for curative radiotherapy for urothelial carcinoma of the bladder

The Rate of Prostatic Involvement in Men Treated With Radical Cystectomy for Muscle Invasive Bladder Cancer

PURPOSE

Radical cystoprostatectomy (RC) is one standard treatment for muscle-invasive bladder cancer (MIBC) in male patients. Another therapeutic option is trimodal therapy. Including the prostate in the trimodal therapy radiation therapy volume is based on MIBC surgical series showing prostatic stromal (PS) involvement. Our aim was to establish the rate of pathologic PS involvement by preoperative T stage in men treated with RC for MIBC.

METHODS AND MATERIALS

We conducted a retrospective review of men with MIBC treated with RC between 2006 and 2019. Electronic medical records were reviewed, and preoperative clinical staging data were collected. χ² test was done to test for a statistically significant difference in the rate of prostatic involvement between clinical tumor (cT) stages. Preoperatively identified carcinoma in situ, lymph node involvement, tumor location, and urethral involvement were also analyzed to see if they conferred a higher risk of PS involvement. Multivariate analysis using multiple logistic regression was performed.

RESULTS

We identified 283 men with bladder cancer treated with RC. Patients with non-MIBC or incomplete medical data were excluded (n = 72). We analyzed 211 patients, and 46 (22%) had pathologic PS involvement. PS involvement by preoperative T stage was cT2 = 18%, cT3 = 23%, and cT4 = 48%. Twenty-nine (12%) patients had clinical lymph node involvement, of whom 19 (76%) had PS involvement. Thirty-four (16%) had urethral involvement, of whom 17 (50%) had PS involvement. Sixteen percent and 17% of percent of clinical T2 and T3 patients had bladder neck/trigone tumors, of whom 57% and 50% had prostatic involvement. Clinical T2 and T3 were not statistically different with regards to PS involvement (P = .385). Preoperative urethral involvement, lymph node involvement, cT4, and bladder neck/trigone location were statistically significant predictors of pathologic PS involvement (all P < .05). On multivariate analysis, only clinical urethral involvement was significant (P < .0001).

CONCLUSIONS

The high rate of pathologic PS involvement seen in cT2 patients and the lack of ability of cT stage to predict PS involvement support routinely treating the prostate in trimodal therapy. Patients with preoperatively identified bladder neck/trigone tumors, urethral involvement, positive lymph nodes, or prostatic involvement are a subset at even higher risk of having pathologic PS involvement.

A practical approach to bladder preservation with hypofractionated radiotherapy for localised muscle-invasive bladder cancer

Bladder preservation with trimodality treatment (TMT) is an alternative strategy to radical cystectomy (RC) for the management of localised muscle invasive bladder cancer (MIBC). TMT comprises of transurethral resection of the bladder tumour (TURBT) followed by radiotherapy with concurrent radiosensitisation. TMT studies have shown neo-adjuvant chemotherapy with cisplatin-based regimens is often given to further improve survival outcomes. A hypofractionated radiotherapy regimen is preferable due to its non-inferiority in local control and late toxicities. Radiosensitisation can comprise concurrent chemotherapy (with gemcitabine, cisplatin or combination fluorouracil and mitomycin), CON (carbogen and nicotinomide) or hyperthermic treatment. Radiotherapy techniques are continuously improving and becoming more personalised. As the bladder is a mobile structure subject to volumetric changes from filling, an adaptive approach can optimise bladder coverage and reduce dose to normal tissue. Adaptive radiotherapy (ART) is an evolving field that aims to overcome this. Improved knowledge of tumour biology and advances in imaging techniques aims to further optimise and personalise treatment.

A retrospective review of the long-term outcomes of online adaptive radiation therapy and conventional radiation therapy for muscle invasive bladder cancer

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Risks with tight adaptive RT margins.

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Cancer control may be poorer if margins tight.

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Prospective studies required.

Background and Purpose

To report long-term outcomes of online image-guided (IG) adaptive radiation therapy (aRT) versus conventional IG radiation therapy (cRT) for bladder preservation in muscle-invasive bladder cancer (MIBC).

Materials and Methods

A retrospective review of patients with histologically proven MIBC who were prescribed radical intent radiation therapy (RT) following trans-urethral resection of bladder tumour (TURBT) was conducted. There were three groups based on their RT treatment modality: conventional RT (cRT), margin 5 mm adaptive RT (aRT5mm) and margin 7 mm adaptive RT (aRT7mm).

Results

171 patients were included in this study, with median age of 79.4 years (41–90). Approximately half of all patients received concurrent chemotherapy. N = 57 underwent cRT, n = 39 underwent aRT5mm, and n = 75 underwent aRT7mm. Response evaluable patients in all three groups (n = 133) had high rates of complete response (CR, 83%) on first post-RT cystoscopy with no significant differences between the groups. At a median follow-up of 54 months, the 5-year freedom from muscle-invasive failure survival (FFMIFS) in the cRT, aRT5mm, and aRT7mm groups were 75%, 59%, and 98%, respectively. The estimated cancer specific survival (CSS) at 5 years were 60%, 30%, and 59%, respectively. The estimated overall survival (OS) at 5 years were 43%, 26%, and 38%, respectively. The incidence of late grade 3 or 4 toxicity was n = 5 in aRT5mm, n = 2 in cRT group, and n = 1 in aRT7mm.

Conclusion

IG aRT with 7 mm expansion for MIBC provides higher rates of FFMIFS, similar 5-year CSS and OS, as well as toxicity outcomes when compared to cRT. aRT with 5 mm expansion with this RT protocol is not recommended for treatment.

Concurrent carbogen and nicotinamide with radiation therapy in muscle invasive bladder cancer: A report on feasibility in the Australian setting

INTRODUCTION

The incidence of bladder cancer increases with age, and elderly patients with muscle invasive bladder cancer (MIBC) are significantly undertreated. Bladder preservation trimodality therapy (BPTT) is an alternative to radical cystectomy in the curative setting. The use of concurrent carbogen and nicotinamide (CON) with radiation therapy (RT) as radiosensitisers have shown significant improvement in the overall survival and local relapse in the UK BCON Trial and is part of the standard of care for patients with MIBC in the UK. This is the first study in the Australian setting to demonstrate the feasibility in setting up a CON radiation oncology department.

METHODS

Based on the UK BCON trial, circuit systems for carbogen gas delivery were set up in consultation with the anaesthetics and respiratory teams. TGA exemption was obtained for 98% oxygen and 2% carbon dioxide carbogen gas mixture and delivery apparatus for each patient. Seven patients with histological locally advanced bladder cancer were recruited into this study.

RESULTS

The establishment of a CON department took approximately 24 months. Development of trial protocol was based on the equipment availability in Australia and proper transport, storage and handling of the equipment was guided by local occupational, health and safety (OHS) regulations. All patients received full of dose of CON. Increased urinary frequency, urgency and diarrhoea were the most commonly reported acute bladder and bowel toxicities.

CONCLUSIONS

This is the first study in Australia to demonstrate the feasibility of concurrent CON with radiation therapy. It is a safe and cost-effective treatment that provides a new therapeutic option in the treatment of patients with MIBC, particularly those with limited treatment options.

Recommendations for planning and delivery of radical radiotherapy for localized urothelial carcinoma of the bladder

PURPOSE

Curative radio-chemotherapy is recognized as a standard treatment option for muscle-invasive bladder cancer (MIBC). Nevertheless, the technical aspects for MIBC radiotherapy are heterogeneous with a lack of practical recommendations.

METHODS AND MATERIALS

In 2018, a workshop identified the need for two cooperative groups to develop consistent, evidence-based guidelines for irradiation technique in the delivery of curative radiotherapy. Two radiation oncologists performed a review of the literature addressing several topics relative to radical bladder radiotherapy: planning computed tomography acquisition, target volume delineation, radiation schedules (total dose and fractionation) and dose delivery (including radiotherapy techniques, image-guided radiotherapy (IGRT) and adaptive treatment modalities). Searches for original and review articles in the PubMed and Google Scholar databases were conducted from January 1990 until March 2020. During a meeting conducted in October 2020, results on 32 topics were presented and discussed with a working group involving 15 radiation oncologists, 3 urologists and one medical oncologist. We applied the American Urological Association guideline development's method to define a consensus strategy.

RESULTS

A consensus was obtained for all 34 except 4 items. The group did not obtain an agreement on CT enhancement added value for planning, PTV margins definition for empty bladder and full bladder protocols, and for pelvic lymph-nodes irradiation. High quality evidence was shown in 6 items; 8 items were considered as low quality of evidence.

CONCLUSION

The current recommendations propose a homogenized modality of treatment both for routine clinical practice and for future clinical trials, following the best evidence to date, analyzed with a robust methodology. The XXX group formulates practical guidelines for the implementation of innovative techniques such as adaptive radiotherapy.

Prospective evaluation of definitive chemoradiotherapy with volumetric modulated arc therapy in patients with muscle invasive carcinoma of urinary bladder

Introduction

Concurrent chemoradiotherapy (CTRT) remains one of the treatment options in patients with muscle invasive bladder cancer (MIBC) unwilling/unsuitable for radical surgery. We evaluated the role of volumetric modulated arc therapy (VMAT) in MIBC patients treated with definitive CTRT.

Material and methods

25 patients of histologically proven transitional cell MIBC (T2–T4a, N0, M0) unwilling/unsuitable for radical surgery (after maximal transurethral resection of bladder tumour) were recruited in this prospective study. Primary clinical target volume (CTV) consisted of the gross tumour and whole bladder. Primary planning target volume (PTV) and nodal PTV were prescribed 60 Gy and 54 Gy (both in 30 fractions). Concurrent chemotherapy was cisplatin (40 mg/m²) weekly. Acute toxicities were assessed as per Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. Survival estimates were done from the date of registration using the Kaplan-Meier method.

Results

Median age was 70 years (37–80 years). Median overall treatment time was 45 days (44–51). Median number of chemotherapy cycles was 5 (range 3–6). 5 (20%) and 4 (16%) patients respectively suffered from acute grade ≥ 2 gastrointestinal and grade ≥ 2 genitourinary toxicities during treatment. One patient each had grade 3 anaemia and neutropenia. At a median follow-up of 34 months (10–45 months), 3-year progression-free survival and overall survival were 65.6% and 81.2% respectively. 3-year distant metastasis-free survival was 90.5%. Bladder preservation rate at 3 years was 68%.

Conclusions

Definitive CTRT with VMAT is well tolerated in patients with MIBC unsuitable for surgery and yields decent survival and bladder preservation outcome.

Outcome of patients with nonmetastatic muscle-invasive bladder cancer not undergoing cystectomy after treatment with noncisplatin-based chemotherapy and/or radiotherapy: a retrospective analysis

Transurethral resection of bladder tumor (TURBT), radiotherapy, chemotherapy, or combinations can be used in patients with muscle-invasive bladder cancer (MIBC) not undergoing cystectomy. Nevertheless, unfitness for cystectomy is frequently associated with unfitness for other therapeutic modalities. We report the outcome of patients with MIBC who did not undergo cystectomy and did not receive cisplatin-based chemotherapy. Selection criteria for the study were nonmetastatic MIBC, no cystectomy, no cisplatin-based chemotherapy. Chemotherapy and/or radiotherapy should have been used aside from TURBT. Forty-nine patients (median age 79), managed between April 2001 and January 2012, were included in this analysis. Median Charlson Comorbidity Index was 5, while 76% were unfit for cisplatin. Treatment included radiotherapy (n = 7), carboplatin-based chemotherapy (n = 25), carboplatin-based chemotherapy followed by radiotherapy (n = 10), and radiochemotherapy (n = 7). Five-year event-free rate was 26% (standard error [SE] = 7) for overall survival, 23% (SE = 7) for progression-free survival, and 30 (SE = 8) for cancer-specific survival (CSS). Patients who were treated with combination of radiotherapy and chemotherapy had significantly longer CSS compared to those treated with radiotherapy or chemotherapy only (5-year CSS rate: 16% [SE 8] vs. 63% [SE 15], P = 0.053). Unfit-for-cystectomy patients frequently receive suboptimal nonsurgical treatment. Their outcome was poor. Combining chemotherapy with radiotherapy produced better outcomes and should be prospectively evaluated.

Bladder Preservation for Muscle Invasive Bladder Cancer

The standard treatment for muscle invasive bladder cancer (MIBC) has been considered to be radical cystectomy (RC) with pelvic lymphadenectomy. However morbidity and impact on quality of life is significant. Radiotherapy has been used in MIBC patients who choose bladder preservation or who are unfit for RC with comparable outcomes. Evidence from some prospective and large retrospective series supports the use of radiotherapy as an attractive alternative option. In this paper we review the evidence and practice of bladder preservation strategies with radiotherapy for muscle invasive bladder cancer.

[Concomitant chemoradiotherapy for muscle-invasive bladder cancer: current knowledge, controversies and future directions]

Radical cystectomy with lymphadenectomy is currently the standard of care for muscle-invasive urothelial bladder cancer; however and because of its morbidity and its impact on quality of life, there is a growing tendency for bladder-sparing strategies. Initially reserved for elderly or unfit patients unable to undergo radical cystectomy, chemoradiotherapy became a true alternative to surgery for highly selected patients. Although there are no randomized trials comparing radical cystectomy with bladder preserving approaches, surgery remains the preferred treatment for many clinicians. Furthermore, comparison is even more difficult as modalities of radiotherapy are not consensual and differ between centers with a variability of protocols, volume of irradiation and type of chemotherapy. Several ongoing trials are attempting to optimize chemoradiotherapy and limit its toxicity, especially through techniques of adaptive radiotherapy or targeted therapies.

Current clinical practice guidelines on chemotherapy and radiotherapy for the treatment of non-metastatic muscle-invasive urothelial cancer: a systematic review and critical evaluation by the Hellenic Genito-Urinary Cancer Group (HGUCG)

Radical cystectomy is the treatment of choice in localized muscle-invasive urothelial cancer. Nevertheless, relapses are frequent and systemic chemotherapy has been employed in order to reduce this risk. In addition, bladder preservation strategies are appealing. During the last decade, there has been a difficulty in conducting and completing large-scale trials in urothelial cancer. This has resulted in relatively few changes in the existing guidelines. Recent studies have created renewed interest in certain fields, such as the role of chemo-radiotherapy and management of unfit patients. In addition, application of certain guidelines has been limited in everyday practice. We conducted a systematic review of the existing guidelines and recent randomized trials not included in these guidelines, and developed a treatment algorithm, regarding non-surgical therapies for non-metastatic, muscle-invasive urothelial cancer based predominantly on patients' fitness for the available therapeutic modalities.

A dosimetric comparison of 3D conformal vs intensity modulated vs volumetric arc radiation therapy for muscle invasive bladder cancer

BACKGROUND

To compare 3 Dimensional Conformal radiotherapy (3D-CRT) with Intensity Modulated Radiotherapy (IMRT) with Volumetric-Modulated Arc Therapy (VMAT) for bladder cancer.

METHODS

Radiotherapy plans for 15 patients with T2-T4N0M0 bladder cancer were prospectively developed for 3-DCRT, IMRT and VMAT using Varian Eclipse planning system. The same radiation therapist carried out all planning and the same clinical dosimetric constraints were used. 10 of the patients with well localised tumours had a simultaneous infield boost (SIB) of the primary tumour planned for both IMRT and VMAT. Tumour control probabilities and normal tissue complication probabilities were calculated.

RESULTS

Mean planning time for 3D-CRT, IMRT and VMAT was 30.0, 49.3, and 141.0 minutes respectively. The mean PTV conformity (CI) index for 3D-CRT was 1.32, for IMRT 1.05, and for VMAT 1.05. The PTV Homogeneity (HI) index was 0.080 for 3D-CRT, 0.073 for IMRT and 0.086 for VMAT. Tumour control and normal tissue complication probabilities were similar for 3D-CRT, IMRT and VMAT. The mean monitor units were 267 (range 250-293) for 3D-CRT; 824 (range 641-1083) for IMRT; and 403 (range 333-489) for VMAT (P < 0.05). Average treatment delivery time were 2:25min (range 2:01-3:09) for 3D-CRT; 4:39 (range 3:41-6:40) for IMRT; and 1:14 (range 1:13-1:14) for VMAT. In selected patients, the SIB did not result in a higher dose to small bowel or rectum.

CONCLUSIONS

VMAT is associated with similar dosimetric advantages as IMRT over 3D-CRT for muscle invasive bladder cancer. VMAT is associated with faster delivery times and less number of mean monitor units than IMRT. SIB is feasible in selected patients with localized tumours.