Conservative treatment with transurethral resection, neoadjuvant chemotherapy followed by radiochemotherapy in stage T2-3 transitional bladder cancer

Approaches to Clinical Complete Response after Neoadjuvant Chemotherapy in Muscle-Invasive Bladder Cancer: Possibilities and Limitations

In the surgical oncology field, the change from a past radical surgery to an organ preserving surgery is a big trend. In muscle-invasive bladder cancer treatment, neoadjuvant chemotherapy (NAC) followed by radical cystectomy (RC) is the standard of care for muscle-invasive bladder cancer (MIBC) patients eligible for cisplatin. There is a growing interest in bladder preserving strategies after NAC because good oncologic outcome has been reported for pathologic complete response (pCR) patients after NAC, and many studies have continued to discuss whether bladder preservation treatment is possible for these patients. However, in actual clinical practice, decision-making should be determined according to clinical staging and there is a gap that cannot be ignored between clinical complete response (cCR) and pCR. Currently, there is a lack in a uniform approach to post-NAC restaging of MIBC and a standardized cCR definition. In this review, we clarify the gap between cCR and pCR at the current situation and focus on emerging strategies in bladder preservation in selected patients with MIBC who achieve cCR following NAC.

The Role of Neoadjuvant Chemotherapy in Bladder Preservation Approaches in Muscle-Invasive Bladder Cancer

Neoadjuvant chemotherapy (NAC), which aims to eliminate micrometastatic disease, has been established as the standard of care for patients with muscle-invasive bladder cancer (MIBC) undergoing radical cystectomy (RC). This is based on randomized controlled trials showing a survival benefit of NAC prior to RC compared to RC alone. It was anticipated that a similar survival benefit would also be seen when NAC was given prior to bladder preserving approaches, but the e phase III RTOG 8903 study which explored this concept was reported to be a negative study. However, there are a number of important caveats to be considered. First, the profile of patients opting for bladder preservation has changed from the older, frailer non-surgical candidates, to now also include younger, fitter patients opting for bladder preservation and who are also more likely to tolerate NAC. In recent years, there have also been important advances in systemic chemotherapy, immunotherapy, radiation techniques, and supportive care. As such revisitng the role of NAC prior to bladder preserving approaches in MIBC appears warranted.

Executive Summary of the American Radium Society Appropriate Use Criteria for Radiation Treatment of Node-Negative Muscle Invasive Bladder Cancer

PURPOSE

Definitive radiation therapy (RT), with or without concurrent chemotherapy, is an alternative to radical cystectomy for patients with localized, muscle-invasive bladder cancer (MIBC) who are either not surgical candidates or prefer organ preservation. We aim to synthesize an evidence-based guideline regarding the appropriate use of RT.

METHODS AND MATERIALS

We performed a Preferred Reporting Items for Systematic Reviews and Meta-analyses literature review using the PubMed and Embase databases. Based on the literature review, critical management topics were identified and reformulated into consensus questions. An expert panel was assembled to address key areas of both consensus and controversy using the modified Delphi framework.

RESULTS

A total of 761 articles were screened, of which 61 were published between 1975 and 2019 and included for full review. There were 7 well-designed studies, 20 good quality studies, 28 quality studies with design limitations, and 6 references not suited as primary evidence. Adjuvant radiation therapy after cystectomy was not included owing to lack of high-quality data or clinical use. An expert panel consisting of 14 radiation oncologists, 1 medical oncologist, and 1 urologist was assembled. We identified 4 clinical variants of MIBC: surgically fit patients who wish to pursue organ preservation, patients surgically unfit for cystectomy, patients medically unfit for cisplatin-based chemotherapy, and borderline cystectomy candidates based on age with unilateral hydronephrosis and normal renal function. We identified key areas of controversy, including use of definitive radiation therapy for patients with negative prognostic factors, appropriate radiation therapy dose, fractionation, fields and technique when used, and chemotherapy sequencing and choice of agent.

CONCLUSIONS

There is limited level-one evidence to guide appropriate treatment of MIBC. Studies vary significantly with regards to patient selection, chemotherapy use, and radiation therapy technique. A consensus guideline on the appropriateness of RT for MIBC may aid practicing oncologists in bridging the gap between data and clinical practice.

Incidence and outcome of salvage cystectomy after bladder sparing therapy for muscle invasive bladder cancer: a systematic review and meta-analysis

Objective

We conducted a systematic review and meta-analysis to assess the available literature regarding the surgical and oncologic outcomes of patients undergoing salvage radical cystectomy (SV-RC) for recurrence or failure of bladder sparing therapy (BST) for muscle-invasive bladder cancer (MIBC).

Methods

We searched MEDLINE (PubMed), EMBASE and Google Scholar databases in May 2020. We included all studies of patients with ≥ cT2N0/xM0 bladder cancer that were eligible for all treatment modalities at the time of treatment decision who underwent BST including radiotherapy (RTX). A meta-analysis was conducted to calculate the pooled rate of several variables associated with an increased need for SV-RC. Study quality and risk of bias were assessed using MINORS criteria.

Results

73 studies comprising 9110 patients were eligible for the meta-analysis. Weighted mean follow-up time was 61.1 months (range 12–144). The pooled rate of non-response to BST and local recurrence after BST, the two primary reasons for SV-RC, was 15.5% and 28.7%, respectively. The pooled rate of SV-RC was 19.2% for studies with a follow-up longer than 5 years. Only three studies provided a thorough report of complication rates after SV-RC. The overall complication rate ranged between 67 and 72% with a 30-day mortality rate of 0–8.8%. The pooled rates of 5 and 10-year disease-free survival after SV-RC were 54.3% and 45.6%, respectively.

Conclusion

Approximately one-fifth of patients treated with BST with a curative intent eventually require SV-RC. This procedure carries a proportionally high rate of complications and is usually accompanied by an incontinent urinary diversion.

Electronic supplementary material

The online version of this article (10.1007/s00345-020-03436-0) contains supplementary material, which is available to authorized users.

The Role of Transurethral Resection in Trimodal Therapy for Muscle-Invasive Bladder Cancer

While radical cystectomy (RC) with pelvic lymph node dissection (PLND) represents the accepted gold standard for the treatment of muscle-invasive bladder cancer, this treatment approach is associated with significant morbidity. As such, bladder preservation strategies are often utilized in patients who are either deemed medically unfit due to significant comorbidities or whom decline management with RC and PLND secondary to its associated morbidity. In a select group of patients, meeting strict criteria, bladder preservation approaches may be employed with curative intent. Trimodal therapy, consisting of complete transurethral resection of bladder tumor (TURBT), chemotherapy, and radiation therapy has demonstrated durable oncologic control and long-term survival in a number of studies. The review presented here provides a description of trimodal therapy and the role of TURBT in bladder preservation for patients with 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.

Critical analysis of bladder sparing with trimodal therapy in muscle-invasive bladder cancer: a systematic review

CONTEXT

Aims of bladder preservation in muscle-invasive bladder cancer (MIBC) are to offer a quality-of-life advantage and avoid potential morbidity or mortality of radical cystectomy (RC) without compromising oncologic outcomes. Because of the lack of a completed randomised controlled trial, oncologic equivalence of bladder preservation modality treatments compared with RC remains unknown.

OBJECTIVE

This systematic review sought to assess the modern bladder-preservation treatment modalities, focusing on trimodal therapy (TMT) in MIBC.

EVIDENCE ACQUISITION

A systematic literature search in the PubMed and Cochrane databases was performed from 1980 to July 2013.

EVIDENCE SYNTHESIS

Optimal bladder-preservation treatment includes a safe transurethral resection of the bladder tumour as complete as possible followed by radiation therapy (RT) with concurrent radiosensitising chemotherapy. A standard radiation schedule includes external-beam RT to the bladder and limited pelvic lymph nodes to an initial dose of 40 Gy, with a boost to the whole bladder to 54 Gy and a further tumour boost to a total dose of 64-65 Gy. Radiosensitising chemotherapy with phase 3 trial evidence in support exists for cisplatin and mitomycin C plus 5-fluorouracil. A cystoscopic assessment with systematic rebiopsy should be performed at TMT completion or early after TMT induction. Thus, nonresponders are identified early to promptly offer salvage RC. The 5-yr cancer-specific survival and overall survival rates range from 50% to 82% and from 36% to 74%, respectively, with salvage cystectomy rates of 25-30%. There are no definitive data to support the benefit of using of neoadjuvant or adjuvant chemotherapy. Critical to good outcomes is proper patient selection. The best cancers eligible for bladder preservation are those with low-volume T2 disease without hydronephrosis or extensive carcinoma in situ.

CONCLUSIONS

A growing body of accumulated data suggests that bladder preservation with TMT leads to acceptable outcomes and therefore may be considered a reasonable treatment option in well-selected patients.

PATIENT SUMMARY

Treatment based on a combination of resection, chemotherapy, and radiotherapy as bladder-sparing strategies may be considered as a reasonable treatment option in properly selected patients.

Radio-chemotherapy for bladder cancer: Contribution of chemotherapy on local control

The purpose of this study was to review the magnitude of contribution of chemotherapy (CT) in the local control of muscle invasive bladder carcinoma in the studies where a combined radio-chemotherapy (RCT) was used (how much higher local control rates are obtained with RCT compared to RT alone). Studies on radiotherapy (RT) and combined RCT, neo-adjuvant, concurrent, adjuvant or combinations, reported after 1990 were reviewed. The mean complete response (CR) rates were significantly higher for the RCT studies compared to RT-alone studies: 75.9% vs 64.4% (Wilcoxon rank-sum test, P = 0.001). Eleven of the included RCT studies involved 2-3 cycles of neo-adjuvant CT, in addition to concurrent RCT. The RCT studies included the one-phase type (where a full dose of RCT was given and then assessment of response and cystectomy for non-responders followed) and the two-phase types (where an assessment of response was undertaken after an initial RCT course, followed 6 wk later by a consolidation RCT for those patients with a CR). CR rates between the two subgroups of RCT studies were 79.6% (one phase) vs 71.6% (two-phase) (P = 0.015). The average achievable tumour control rates, with an acceptable rate of side effects have been around 70%, which may represent a plateau. Further increase in CR response rates demands for new chemotherapeutic agents, targeted therapies, or modified fractionation in various combinations. Quantification of RT and CT contribution to local control using radiobiological modelling in trial designs would enhance the potential for both improved outcomes and the estimation of the potential gain.

Trimodality treatment in the conservative management of infiltrating bladder cancer: a critical review of the literature

Although radical cystectomy is still the treatment of choice for patients with infiltrating bladder cancer, there is growing evidence of the effectiveness of a conservative approach. Developed as a treatment of need for elderly or unfit patients unable to undergo radical cystectomy, conservative therapy is becoming a true alternative to surgery for highly selected patients. Although transurethral bladder resection, external radiotherapy and systemic chemotherapy can control the disease as single treatments, the best results have been observed when they are combined. Moreover, new irradiation techniques and new-generation drugs are now being tested in an attempt to improve disease control further. Conservative management requires the multidisciplinary involvement of different specialties in order to give patients a real alternative to surgical treatment.

Expression of TIP60 (tat-interactive protein) and MRE11 (meiotic recombination 11 homolog) predict treatment-specific outcome of localised invasive bladder cancer

What's known on the subject? and What does the study add? Several studies have shown that defects in DNA-damage response are associated with good survival after chemotherapy and radiotherapy. Furthermore, loss of cell cycle regulators may be prognostic indicators of poor survival after cystectomy. However, the potential clinical impact of previous findings is hampered by insufficient validation of significant results in suitable cystectomy and radiotherapy cohorts. Here we use a large cohort of patients receiving radiotherapy to successfully validate the importance of MRE11 as a predictive marker of disease-specific survival (DSS). Furthermore, using two independent patient cohorts we show for the first time that TIP60 is a predictive marker of DSS after cystectomy. We show that combined use of TIP60 and MRE11 may hold the potential to guide treatment decisions.

OBJECTIVE

• To determine the association between the proteins: tat-interactive protein 60 kDa (TIP60), p16, meiotic recombination 11 homolog (MRE11), phosphorylated ataxia telangiectasia mutated (ATM), retinoblastoma protein (Rb), Ki67, and p53 and clinical outcome in invasive lymph node-negative bladder cancer.

PATIENTS AND METHODS

• Protein expression was measured by immunohistochemistry in cancer specimens from two independent cohorts of patients with bladder cancer treated with cystectomy (162 patients and 273) and one cohort of patients receiving radiotherapy (148). • Disease-specific survival (DSS) was used as the outcome measure, and patients with no disease-specific death were followed for a minimum of 36 months.

RESULTS

• TIP60 was significantly correlated with DSS in both cystectomy cohorts (hazard ratio [HR] 0.42, 95% confidence interval [CI] 0.26-0.68, P < 0.001 and HR 0.45, 95% CI 0.28-0.72, P = 0.001). • MRE11 was significantly correlated with DSS in the cohort receiving radiotherapy (HR 0.64, 95% CI 0.47-0.86, P = 0.005). • P16 was significantly correlated with DSS in all three cohorts (HR 0.46, 95% CI 0.30-0.75, P = 0.032; HR 0.60, 95% CI 0.37-0.97, P = 0.032; HR 0.52, 95% CI 0.28-0.96, P = 0.001). • Rb was significantly correlated with DSS in one cystectomy cohort (HR 1.71, 95% CI 1.13-2.75, P = 0.017). • Ki67, p53, and pATM were not significantly correlated with DSS in any of the cohorts.

CONCLUSIONS

• TIP60 protein expression was a predictive marker for DSS after cystectomy in two independent cohorts. This novel marker was the strongest predictive factor in multivariate analysis in patients receiving cystectomy. • MRE11 was shown to be a predictive marker for DSS after radiotherapy. • We have shown that TIP60 and MRE11 hold the potential to guide patients with invasive bladder cancer to either cystectomy or radiotherapy. This study was based on retrospective material and consequently we suggest that these markers should be validated in a prospective study.

Conservative treatment of invasive bladder cancer

The concept of organ-preserving therapies is a trend in modern oncology, and several tumour types are now treated in this fashion. Trimodality therapy consisting of as thorough a transurethral resection of the bladder tumour as is judged safe, followed by concomitant chemoradiation therapy, is emerging as an attractive alternative for bladder preservation in selected patients with muscle-invasive bladder cancer. Long-term data from multiple institutional and cooperative group studies have shown that this approach is safe and effective and that it provides patients with the opportunity to maintain an intact and functional bladder with a survival rate similar to that for modern radical cystectomy.

Bladder-sparing, combined-modality approach for muscle-invasive bladder cancer: a multi-institutional, long-term experience

BACKGROUND

The authors evaluated their long-term experience with combined-modality, conservative treatment in patients with muscle-invasive bladder cancer.

METHODS

In total, 121 patients with T2, T3, or T4 bladder cancer (mean age, 63 years; ratio of men to women, 3:1) underwent induction by transurethral resection (TUR) of the tumor and received 2 cycles of neoadjuvant chemotherapy followed by radiotherapy (RT) (n = 43 patients) or radiochemotherapy (RCT) (n = 78 patients). Six weeks after RT or RCT, responses were evaluated by restaging TUR. Patients who achieved a complete response (CR) were observed at regular intervals. In patients who had persistent or recurrent invasive tumor, further treatment was recommended.

RESULTS

Local response evaluation by restaging TUR was possible in 119 patients, and 102 of those patients (85.7%) achieved a CR. After a median follow-up of 66 months (range, 6-182 months), no local or distant disease recurrences were observed in 67 of 102 complete responders (65.7%), 17 of 102 complete responders (16.7%) experienced superficial local disease recurrence, and 18 of 102 complete responders (17.6%) had a muscle-invasive relapse. The 5-year tumor-specific, overall, and bladder-intact survival rates were 73.5%, 67.7%, and 51.2%, respectively. Treatment modality, tumor classification, and resection status after initial TUR had an impact on survival rates (P = .04, P = .02, and P = .02, respectively).

CONCLUSIONS

The current results indicated that conservative combined treatment is a reasonable alternative to radical cystectomy in selected patients with muscle-invasive bladder cancer.