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

The effect of incidental dose to pelvic nodes in bladder-only irradiation in the era of IMRT: a dosimetric study

PURPOSE

While three-dimensional radiotherapy (RT) causes high incidental nodal doses in bladder-only irradiation for muscle-invasive bladder cancer (MIBC), the impact on pelvic lymphatics is unclear in the era of intensity-modulated RT (IMRT). This study evaluates incidental doses to pelvic lymphatics in MIBC patients treated with IMRT.

METHODS

The data of 40 MIBC patients treated with bladder-only IMRT and concurrent chemotherapy were retrospectively evaluated. The pelvic lymphatics were contoured on initial simulation images and incidental nodal doses were evaluated. The Statistical Package for the Social Sciences (SPSS) version 23.0 (IBM, Armonk, NY, USA) was used for statistics.

RESULTS

Median RT dose to the bladder was 60 Gy in 30 fractions. In dosimetric analysis, median values of mean dose (Dmean) of the obturator, presacral, external iliac, internal iliac, and distal common iliac lymphatics were 33 Gy (range 4-50 Gy), 3 Gy (range 1-28 Gy), 9.5 Gy (range 3-41 Gy), 7.5 Gy (range 2-14 Gy), and 1 Gy (range 0-15 Gy), respectively. The Dmean of the obturator lymphatics was significantly higher (p < 0.001) and the Dmean of the distal common iliac lymphatics was significantly lower (p < 0.001) than all remaining lymphatic stations. The Dmean of the external iliac lymphatics was significantly higher than that of the presacral lymphatics (p < 0.001), but the difference with the internal iliac lymphatics was not statistically significant (p = 0.563).

CONCLUSION

The incidental nodal doses with bladder-only IMRT are heterogeneous and remain below the generally accepted doses for microscopic disease eradication for bladder cancer.

Is trimodal therapy the current standard for muscle-invasive bladder cancer?

OBJECTIVE

The aim of this review is to summarize the current evidence and future perspectives of bladder-sparing treatment for MIBC.

METHODS

A non-systematic literature search in Medline/Pubmed was performed in October 2023 with the following keywords "bladder cancer", "bladder-sparing", "trimodal therapy", "chemoradiation", "biomarkers", "immunotherapy", "neoadjuvant chemotherapy", "radiotherapy".

RESULTS

Urology guidelines recommend radical cystectomy as the standard curative treatment for muscle-invasive urothelial bladder cancer, reserving radiotherapy for patients who are unfit or who want to preserve their bladder. Given the morbidity and mortality of cystectomy and its impact on quality of life and bladder function, modern oncologic therapies are increasingly oriented toward organ preservation and maximizing functional outcomes while maintaining treatment efficacy. Trimodal therapy, which incorporates maximal transurethral resection followed by radiotherapy with concurrent radiosensitizing chemotherapy, is an effective regimen for bladder function preservation in well-selected patients. Despite the absence of comparative data from randomized trials, the two approaches seem to provide comparable oncologic outcomes. Studies are evaluating the expansion of eligibility criteria for trimodal therapy, the optimization of radiotherapy and immunotherapy delivery to further improve outcomes, and the validation of biomarkers to guide bladder preservation.

CONCLUSIONS

Trimodal therapy has shown acceptable outcomes for bladder preservation; therefore, it provides a valid treatment option in well-selected patients.

Trimodal therapy vs radical cystectomy in patients with muscle-invasive bladder cancer: a systematic review and meta-analysis of comparative studies

OBJECTIVE

To perform a systematic review and meta-analysis of trials comparing trimodal therapy (TMT) and radical cystectomy (RC), evaluating differences in terms of oncological outcomes, quality of life, and costs.

MATERIALS AND METHODS

In July 2023, a literature search of multiple databases was conducted to identify studies analysing patients with cT2-4 N any M0 muscle-invasive bladder cancer (MIBC; Patients) receiving TMT (Intervention) compared to RC (Comparison), to evaluate survival outcomes, recurrence rates, costs, and quality of life (Outcomes). The primary outcome was overall survival (OS). Secondary outcomes were cancer-specific survival (CSS) and metastasis-free survival (MFS). Hazard ratios (HRs) were used to analyse survival outcomes according to different treatment modalities and odds ratios were used to evaluate the likelihood of receiving each type of treatment according to T stage.

RESULTS

No significant difference in terms of OS was observed between RC and TMT (HR 1.07, 95% confidence interval [CI] 0.81-1.4; P = 0.6), even when analysing radiation therapy regimens ≥60 Gy (HR 1.02, 95% CI 0.69-1.52; P = 0.9). No significant difference was observed in CSS (HR 1.12, 95% CI 0.79-1.57, P = 0.5) or MFS (HR 0.88, 95% CI 0.66-1.16; P = 0.3). The mean cost of TMT was significantly higher than that of RC ($289 142 vs $148 757; P < 0.001), with greater effectiveness in terms of cost per quality-adjusted life-year. TMT ensured significantly higher general quality-of-life scores.

CONCLUSION

Trimodal therapy appeared to yield comparable oncological outcomes to RC concerning OS, CSS and MFS, while providing superior patient quality of life and cost effectiveness.

The role of radiation therapy for de novo metastatic bladder and renal cancers

Metastatic bladder and renal cancers account respectively for 2.1% and 1.8% of cancer deaths worldwide. The advent of immune checkpoint inhibitors has revolutionized the management of metastatic disease, by demonstrating considerable improvements in overall survival. However, despite initial sensitivity to immune checkpoint inhibitors for most patients, both bladder and renal cancer are associated with short progression-free survival and overall survival, raising the need for further strategies to improve their efficacy. Combining systemic therapies with local approaches is a longstanding concept in urological oncology, in clinical settings including both oligometastatic and polymetastatic disease. Radiation therapy has been increasingly studied with either cytoreductive, consolidative, ablative or immune boosting purposes, but the long-term impact of this strategy remains unclear. This review intends to address the impact of radiation therapy with either curative or palliative intent, for synchronous de novo metastatic bladder and renal cancers.

Managing postoperative biochemical relapse in prostate cancer, from the perspective of the Francophone group of Urological radiotherapy (GFRU)

Up to 50% of patients treated with radical surgery for localized prostate cancer may experience biochemical recurrence that requires appropriate management. Definitions of biochemical relapse may vary, but, in all cases, consist of an increase in a PSA without clinical or radiological signs of disease. Molecular imaging through to positron emission tomography has taken a preponderant place in relapse diagnosis, progressively replacing bone scan and CT-scan. Prostate bed radiotherapy is currently a key treatment, the action of which should be potentiated by androgen deprivation therapy. Nowadays perspectives consist in determining the best combination therapies, particularly thanks to next-generation hormone therapies, but not exclusively. Several trials are ongoing and should address these issues. We present here a literature review aiming to discuss the current management of biochemical relapse in prostate cancer after radical surgery, in lights of recent findings, as well as future perspectives.

Fractionation versus Adaptation for Compensation of Target Volume Changes during Online Adaptive Radiotherapy for Bladder Cancer: Answers from a Prospective Registry

Online adaptive radiotherapy (ART) allows adaptation of the dose distribution to the anatomy captured by with pre-adaptation imaging. ART is time-consuming, and thus intra-fractional deformations can occur. This prospective registry study analyzed the effects of intra-fraction deformations of clinical target volume (CTV) on the equivalent uniform dose (EUDCTV) of focal bladder cancer radiotherapy. Using margins of 5-10 mm around CTV on pre-adaptation imaging, intra-fraction CTV-deformations found in a second imaging study reduced the 10th percentile of EUDCTV values per fraction from 101.1% to 63.2% of the prescribed dose. Dose accumulation across fractions of a series was determined with deformable-image registration and worst-case dose accumulation that maximizes the correlation of cold spots. A strong fractionation effect was demonstrated-the EUDCTV was above 95% and 92.5% as determined by the two abovementioned accumulation methods, respectively, for all series of dose fractions. A comparison of both methods showed that the fractionation effect caused the EUDCTV of a series to be insensitive to EUDCTV-declines per dose fraction, and this could be explained by the small size and spatial variations of cold spots. Therefore, ART for each dose fraction is unnecessary, and selective ART for fractions with large inter-fractional deformations alone is sufficient for maintaining a high EUDCTV for a radiotherapy series.

Prevention of local symptoms in muscle invasive bladder cancer patients: clinical significance of local radiation therapy

PURPOSE

To evaluate the significance of local radiation therapy (LRT) for prevention of local symptoms (LSs) caused by muscle-invasive bladder cancer (MIBC).

METHODS

We retrospectively reviewed the clinical records of 133 patients from 13 hospitals. MIBC patients with or without metastases who were treated with LRT alone from January 2015 through December 2020 were enrolled. Exclusion criteria were urinary diversion (UD) prior to LRT, non-MIBC, or lack of clinical information. LSs were defined as hematuria requiring invasive treatment or transfusion, UD after LRT, bladder tamponade, and opioid use for bladder pain.

RESULTS

One hundred fourteen patients were finally enrolled in the study. During the median follow-up period of 13.5 months, 30 patients (26.3%) had LSs. Risk factors of LSs in multivariate analysis were a prior history of non-MIBC (NMIBC) (hazard ratio [HR] 2.99; 95% confidence interval [CI], 1.36 to 6.56; P < 0.01), radiation dose of less than 50 Gray (Gy) (HR 3.99; 95% CI, 1.80 to 8.82; P < 0.01), and tumor stage 3 or more (HR 2.43; 95% CI, 1.14 to 5.21; P = 0.02). Risk factors of overall survival (OS) in multivariate analysis were being female (HR 3.32; 95% CI, 1.68 to 6.58; P < 0.01), an age-adjusted Charlson Comorbidity index of 6 or more (HR 2.19; 95% CI, 1.18 to 4.10; P = 0.01), distant metastases (HR 3.20; 95% CI, 1.39 to 6.58; P < 0.01), and tumor size of 40 mm or more (HR 2.38; 95% CI, 1.34 to 4.52; P < 0.01). Toxicity (all grades) occurred in 40.4% of the patients, 4.8% with grade 3 or more and 95.2% with lower grades.

CONCLUSIONS

We determined the risk factors for LSs in MIBC patients treated with LRT alone. An escalated-dose of 50 Gy or more may contribute to prevention of LSs caused by MIBC. Thus, dose-escalated LRT for MIBC patients who can expect favorable survival may be a good option to avoid future annoying LSs.

A Brief Review of Artificial Intelligence in Genitourinary Oncological Imaging

Genitourinary (GU) system is among the most commonly involved malignancy sites in the human body. Imaging plays a crucial role not only in diagnosis of cancer but also in disease management and its prognosis. However, interpretation of conventional imaging methods such as CT or MR imaging (MRI) usually demonstrates variability across different readers and institutions. Artificial intelligence (AI) has emerged as a promising technology that could improve the patient care by providing helpful input to human readers through lesion detection algorithms and lesion classification systems. Moreover, the robustness of these models may be valuable in automating time-consuming tasks such as organ and lesion segmentations. Herein, we review the current state of imaging and existing challenges in GU malignancies, particularly for cancers of prostate, kidney and bladder; and briefly summarize the recent AI-based solutions to these challenges.

A shift from simple to sophisticated: using intensity-modulated radiation therapy in conventional nonstereotactic palliative radiotherapy

PURPOSE OF REVIEW

The authors aimed to highlight trends in, and evidence underlying the use of highly conformal radiotherapy (RT) techniques in conventional nonstereotactic palliative RT. The authors reviewed palliative-intent and curative-intent studies relevant to the use of intensity-modulated radiation therapy (IMRT) for the delivery of nonstereotactic conventional regimens to the brain, head and neck, thorax, abdomen and pelvis, and bone metastases.

RECENT FINDINGS

The use of IMRT has become standard with certain indications for brain metastases such as hippocampus-avoiding/limiting whole brain RT. IMRT in the treatment of bone metastases is increasing at many institutions despite limited data comparing its effectiveness with that of fluoroscopy-based and three-dimensional conformal radiation therapy techniques. There is scant data describing the use of IMRT for palliation in other extracranial anatomic sites; guidance for its use in these settings must be gleaned almost exclusively from curative-intent randomized trials, consensus recommendations and contouring atlases.

SUMMARY

Consistent with historical technology shifts in RT practice, the uptake of highly conformal techniques such as IMRT for conventional palliative RT will likely outpace rigorous evaluations of their advantages and disadvantages relative to simpler techniques. Opportunities exist in virtually all anatomic sites for observational and randomized studies to evaluate the clinical impacts of these modern techniques in the palliative setting.

Multidisciplinary Management and Radiotherapy Recommendations for Clinically and Pathologically Node-positive Bladder Cancer

There are limited data regarding the optimal management of patients with pelvic node-positive, but non-metastatic, bladder cancer. Increasing data demonstrate that this is a distinct clinical entity with outcomes bridging between bladder-confined muscle-invasive bladder cancer and metastatic advanced bladder cancer. Guidelines and staging systems have formalized the need to incorporate the unique considerations of management of pelvic node-positive bladder cancer. However, there remains an absence of a definite standard of care. Treatment options include systemic therapy alone, neoadjuvant chemotherapy followed by radical cystectomy, or bladder-preserving trimodality therapy. Furthermore, ongoing studies aim to determine the benefit of incorporating immunotherapy into these treatment paradigms. In this review article, we will discuss the key considerations for management of patients with pelvic node-positive bladder cancer.

French AFU Cancer Committee Guidelines - Update 2022-2024: Muscle-Invasive Bladder Cancer (MIBC)

OBJECTIVE

To update the CCAFU recommendations for the management of muscle invasive bladder carcinoma (MIBC).

METHODS

A systematic review (Medline) of the literature from 2020 to 2022 was performed taking account of the diagnosis, treatment options and surveillance of NMIBC and MIBC, while evaluating the references with their levels of evidence.

RESULTS

MIBC is diagnosed after the most complete tumour resection possible. MIBC grading is based on CTU along with chest CT. Multiparametric pelvic MRI could be an alternative. Cystectomy with extensive lymphadenectomy is the gold standard treatment for non-metastatic MIBC. It should be preceded by platinum-based neoadjuvant chemotherapy in patients in good general health with satisfactory renal function. Enterocystoplasty is proposed in men and women in the absence of contraindications and when the urethral resection is negative on extemporaneous examination. Otherwise, transileal cutaneous ureterostomy is the recommended method of urinary diversion. Inclusion of all patients in an ERAS (Enhanced Recovery After Surgery) protocol is recommended. For metastatic MIBC, first line treatment with platinum-based chemotherapy (GC or MVAC) is recommended, if general health (PS>1) and renal function (clearance>60mL/min) so allow (only 50% of the cases). Pembrolizumab immunotherapy has demonstrated an overall survival benefit in second-line treatment.

CONCLUSION

Updating the ccAFU recommendations should contribute to improving patient management, as well as the diagnosis and decision-making concerning MIBC treatment.

[Bladder-sparing trimodal therapy for muscle invasive bladder cancer]

Organ-sparing strategies in the management of local or locally advanced cancers meet a dual objective: tumor control and preservation of the function of the involved organ. Given the morbidity and mortality of cystectomy and its impact on quality of life and bladder function, bladder-sparing strategies have emerged for the management of urothelial muscle invasive bladder cancer, mostly through trimodal treatment, which consists in maximal trans-urethral resection of bladder tumor, followed by chemo-radiotherapy. This review presents the modalities of trimodal treatment, before exposing the advantages and limitations of this strategy compared to cystectomy among operable patients. Despite the absence of comparative data from randomized trials, the two approaches seem to provide similar oncological results among appropriately selected patients. In modern series, the rate of salvage cystectomy is approximately 15% at 5 years; this delayed cystectomy does not seem to be associated with greater morbidity and mortality as compared to upfront cystectomy. Emphasis is placed in the review on quality of life data of these two approaches. In order to optimize the selection of patients eligible to trimodal therapy, the classical predictive factors of response to radio(chemo)therapy are critically analyzed, with the perspective of innovative molecular biomarkers. Finally, a close multidisciplinary collaboration is needed for the choice and the execution of the therapeutic strategy, and the patient should be fully involved in the decision-making process.

Phase 1 Study of Chemoradiotherapy Combined with Nivolumab ± Ipilimumab for the Curative Treatment of Muscle-invasive Bladder Cancer

BACKGROUND

Muscle-invasive bladder cancer (MIBC) has a poor prognosis. Chemoradiotherapy (CRT) in selected patients has comparable results to radical cystectomy. Results of neoadjuvant immune checkpoint inhibitors (ICIs) before radical cystectomy are promising. We hypothesize that ICI concurrent to CRT (iCRT) is safe and may improve treatment outcomes.

OBJECTIVE

To determine the safety of iCRT for MIBC.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter, phase 1b, open-label, dose-escalation study determined the safety of CRT with three ICI regimens in patients with nonmetastatic (T2-4aN0-1) MIBC. Twenty-six patients received mitomycin C/capecitabine and 20 × 2.75 Gy to the bladder. Tolerability was evaluated in a cohort of up to ten patients. If two or fewer out of the first six patients or three or fewer of ten patients experienced dose-limiting toxicity (DLT), accrual continued in the next cohort.

INTERVENTION

Patients received nivolumab 480 mg (NIVO480), nivolumab 3 mg/kg and ipilimumab 1 mg/kg (NIVO3 + IPI1), or nivolumab 1 mg/kg and ipilimumab 3 mg/kg (IPI3 + NIVO1).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was safety. Secondary objectives were response rate, disease-free survival, metastatic-free survival (MFS), and overall survival (OS).

RESULTS AND LIMITATIONS

In the NIVO480 cohort, no patients experienced DLT. The NIVO3 + IPI1 2 patients experienced DLT, thrombocytopenia (grade 4), and asystole (grade 5). IPI3 + NIVO1 was discontinued after three out of six patients experienced DLT. Clinically significant adverse events (AEs) of grade ≥3 occurred in zero, three, and five patients in the NIVO480, NIVO3 + IPI1, and IPI3 + NIVO1 groups, respectively. The most common AEs were immune related and gastrointestinal. MFS and OS were 90% at 2 yr for NIVO480 and 90% at 1 yr for NIVO3 + IPI1. Limitations include the absence of a centralized pathology and radiology review, and a lack of biomarker analysis.

CONCLUSIONS

In this dose-finding study of iCRT, the regimens of nivolumab monotherapy and nivolumab 3 mg/kg with ipilimumab 1 mg/kg have acceptable toxicity.

PATIENT SUMMARY

We tested the safety of a new bladder-sparing treatment modality for muscle-invasive bladder cancer patients, combining immune checkpoint inhibitors simultaneously with chemoradiotherapy. We report that two regimens, nivolumab monotherapy and nivolumab 3 mg/kg with ipilimumab 1 mg/kg, are safe and can be used in phase 3 trials.

A Multicenter Retrospective Cohort Series of Muscle-invasive Bladder Cancer Patients Treated with Definitive Concurrent Chemoradiotherapy in Daily Practice

Background

Concurrent chemoradiotherapy (CRT) as a definitive treatment option for patients with nonmetastatic muscle-invasive bladder carcinoma (MIBC) is increasingly being applied in clinical practice.

Objective

To assess the oncological and toxicity outcomes in a contemporary cohort of nonmetastatic MIBC patients treated with concurrent CRT in daily practice.

Design, setting, and participants

Patients with nonmetastatic MIBC (cT2-4aN0M0) who had received CRT with curative intent between January 2010 and April 2020 in three centers were retrospectively identified. The CRT consisted of 66 Gy (or biologically equivalent) plus either mitomycin C and fluorouracil/capecitabine or cisplatinum.

Outcome measurements and statistical analysis

The primary endpoint was the 2-yr locoregional disease-free survival (LDFS) estimate. Secondary endpoints were complete response, disease-specific survival (DSS), overall survival (OS), bladder intact event-free survival (BI-EFS), and severe adverse events (<90 d of starting CRT). Kaplan-Meier survival and Cox multivariable regression analyses were performed.

Results and limitations

We included data of 240 MIBC patients with a median age of 74 yr and a median follow-up of 27 mo (interquartile range 11–44). Complete response on first cystoscopy after CRT was seen in 209 cases (90%). The 2-yr LDFS was 76% (95% confidence interval [CI] 70–82%); the 5-yr OS and DSS were 50% (95% CI 42–59%) and 70% (95% CI 62–79%), respectively. On multivariable analysis, cT2 versus cT3–4 tumor stage was significantly associated with better DSS (hazard ratio 1.02, 95% CI 1–1.05, p = 0.024). The 2-yr BI-EFS was 75% (95% CI 69–82%). Forty-three (17%) patients experienced a severe adverse event (grade ≥3). Limitations include retrospective design and heterogeneous administration of CRT.

Conclusions

Concurrent CRT is a safe and effective treatment modality for nonmetastatic MIBC.

Patient summary

Chemoradiotherapy for the treatment of muscle-invasive bladder carcinoma is increasingly being applied. In this study, we reviewed the outcomes of this bladder-sparing treatment using a series of patients treated in three hospitals in daily practice. We found that administration of chemoradiotherapy can be safe and effective.

Oncologic Impact and Safety of Pre-Operative Radiotherapy in Localized Prostate and Bladder Cancer: A Comprehensive Review from the Cancerology Committee of the Association Française d'Urologie

Simple Summary

Radiotherapy may have an interesting role of reinforcing the loco-regional control of cancer, in addition to surgery, when used as a preoperative treatment. This sequence has demonstrated its efficacy and safety in various malignancies, but no strong data exist in the era of uro-oncology. In this review article, we aim to highlight the potential usefulness of preoperative radiotherapy in prostate and muscle-invasive bladder cancer, aiming to enhance pathological response and local control and to prevent intraoperative tumor seeding. We also emphasize the need for further clinical studies assessing the functional safety of subsequent surgical procedures in a competitive context of new systemic agents that have proven to demonstrate a survival benefit in locally advanced urologic cancers.

Abstract

Preoperative radiotherapy (RT) is commonly used for the treatment of various malignancies, including sarcomas, rectal, and gynaecological cancers, but it is preferentially used as a competitive treatment to radical surgery in uro-oncology or as a salvage procedure in cases of local recurrence. Nevertheless, preoperative RT represents an attractive strategy to prevent from intraoperative tumor seeding in the operative field, to sterilize microscopic extension outside the organ, and to enhance the pathological and/or imaging tumor response rate. Several clinical works support this research field in uro-oncology. In this review article, we summarized the oncologic impact and safety of preoperative RT in localized prostate and muscle-invasive bladder cancer. Preliminary studies suggest that both modalities can be complementary as initial primary tumor treatments and that a pre-operative radiotherapy strategy could be beneficial in a well-defined population of patients who are at a very high-risk of local relapse. Future prospective trials are warranted to evaluate the oncologic benefit of such a combination of local treatments in addition to new life-prolonging systemic therapies, such as immunotherapy, and new generation hormone therapies. Moreover, the safety and the feasibility of salvage surgical procedures due to non-response or local recurrence after pelvic RT remain poorly evaluated in that context.

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.