Comparative survival analysis of bladder preservation therapy versus radical cystectomy in muscle-invasive bladder cancer

BACKGROUND

Bladder preservation therapy is an alternative to radical cystectomy in patients with muscle-invasive bladder cancer (MIBC). The purpose of this study is to compare survival outcomes between bladder preservation therapy and radical cystectomy in MIBC patients using an Asian nationwide cancer registry database.

METHODS

From the Taiwan Cancer Registry database and the Taiwan National Health Insurance Research Database, we identified bladder cancer patients from 2008 to 2018. The patients with urothelial carcinoma and clinical stage T2-T4aN0-1 M0 were included. Propensity score matching by age, gender, clinical stage, cT classification, and Charlson Comorbidity Index score was used between those receiving bladder preservation therapy or radical cystectomy. Overall survival (OS), cancer-specific survival (CSS), and disease-free survival (DFS) were compared using the Kaplan-Meier method. Multivariate Cox regression models were used to determine the predictive factors of OS, CSS, and DFS.

RESULTS

Following the propensity score matching, 393 MIBC patients were analyzed, 131 (33.3%) receiving bladder preservation therapy and 262 (66.7%) receiving radical cystectomy. After 5 years of the follow-up period the overall duration was with a median of 15.6 months. The treatment groups did not differ significantly in OS, CSS, and DFS (p = 0.2681, 0.7208, and 0.3616, respectively). In multivariable Cox regression models, bladder preservation therapy remained non-inferior to radical cystectomy in OS (adjusted hazard ratio [aHR] 1.08; 95% confidence interval [CI], 0.77-1.50; p = 0.6689), CSS (aHR, 1.06; 95% CI, 0.72-1.57; p = 0.7728), and DFS (aHR, 0.76; 95% CI, 0.46-1.27; p = 0.2929). Additionally, among patients ≥80 years, the use of bladder preservation therapy compared with radical cystectomy resulted in an equivalent OS, CSS and DSS.

CONCLUSION

In Asian populations, bladder preservation therapy yielded similar survival outcomes as radical cystectomy in MIBC patients. Based on the results, it is evident that a multidisciplinary approach and shared decision-making are recommended for bladder cancer treatment.

Bladder-sparing approaches for muscle invasive bladder cancer: a narrative review of current evidence and future perspectives

Background and Objective

In recent years, the application of less-invasive "bladder-sparing" trimodal therapy (TMT) in selected muscle-invasive bladder cancer (MIBC) patients unfit for or who declined radical cystectomy (RC) has been increasing. This review aims to summarize the current evidence and future perspectives of bladder-sparing therapy for MIBC.

Methods

A non-systematic Medline/PubMed literature search was conducted on July 2022 with the following keywords 'MIBC', 'bladder-sparing', 'chemotherapy', 'radiotherapy', 'trimodal', 'multimodal', and 'immunotherapy'.

Key Content and Findings

All monotherapies are inferior to RC or combination therapy and should not be routinely used for curative intent. Radiotherapy (RT) alone has been shown to have poorer outcomes when compared to chemoradiotherapy. The ideal selection criteria for TMT include good bladder function and capacity, clinical stage within cT2, complete transurethral resection of bladder tumor (TURBT), no prior history of pelvic RT, no extensive carcinoma in situ (CIS), and absence of hydronephrosis. The emergence of immunotherapy may further increase the effect of bladder-sparing therapy. Novel predictive biomarkers are awaited for more precise patient selection and better oncological outcomes.

Conclusions

TMT is a well-tolerated and offers a curative alternative approach to RC for selected patients with localized MIBC. Appropriate patient selection and a multi-disciplinary approach is crucial in achieving good oncologic control with bladder-sparing therapy.

Proton beam therapy for muscle-invasive bladder cancer: A systematic review and analysis with Proton-Net, a multicenter prospective patient registry database

To assess the safety and efficacy of proton beam therapy (PBT) for muscle-invasive bladder cancer (MIBC), we examined the outcomes of 36 patients with MIBC (cT2-4aN0M0) who were enrolled in the Proton-Net prospective registry study and received PBT with concurrent chemotherapy from May 2016 to June 2018. PBT was also compared with X-ray chemoradiotherapy in a systematic review (X-ray (photon) radiotherapy). The radiotherapy consisted of 40-41.4 Gy (relative biological effectiveness (RBE) delivered in 20-23 fractions to the pelvic cavity or the entire bladder using X-rays or proton beams, followed by a boost of 19.8-36.3 Gy (RBE) delivered in 10-14 fractions to all tumor sites in the bladder. Concurrently, radiotherapy was given with intra-arterial or systemic chemotherapy of cisplatin alone or in combination with methotrexate or gemcitabine. Overall survival (OS), progression-free survival (PFS) and local control (LC) rates were 90.8, 71.4 and 84.6%, respectively, after 3 years. Only one case (2.8%) experienced a treatment-related late adverse event of Grade 3 urinary tract obstruction, and no severe gastrointestinal adverse events occurred. According to the findings of the systematic review, the 3-year outcomes of XRT were 57-84.8% in OS, 39-78% in PFS and 51-68% in LC. The weighted mean frequency of adverse events of Grade 3 or higher in the gastrointestinal and genitourinary systems was 6.2 and 2.2%, respectively. More data from long-term follow-up will provide us with the appropriate use of PBT and validate its efficacy for MIBC.

Impact of sarcopenia in bladder preservation therapy for muscle-invasive bladder cancer patients: a narrative review

BACKGROUND AND OBJECTIVE

Muscle-invasive bladder cancer (MIBC) is a biologically aggressive disease and its prognosis is poor. Radical cystectomy (RC) with urinary diversion and lymph node dissection is the gold standard treatment for MIBC patients. Accumulating evidence indicates that sarcopenia, the degenerative and systemic loss of skeletal muscle mass, is a significant predictor of higher rates of mortality and perioperative complications following RC. Recently, bladder preservation therapy has been offered as an alternative in appropriately selected MIBC patients who desire to preserve their bladders and those unfit or unwilling for RC. Here, we performed a narrative review on the impact of sarcopenia on oncological outcomes and complication rates in MIBC patients treated with bladder preservation therapy.

METHODS

A literature review was performed using the PubMed and Scopus databases.

KEY CONTENT AND FINDINGS

We identified two studies reported the impact of sarcopenia on responses to trimodal therapy and survival outcomes in MIBC patients. Consolidative partial cystectomy was performed in patients who achieved clinical complete response (CR) to trimodal therapy in one of the two studies. In both studies, CR rates to trimodal therapy are comparable between sarcopenic and non-sarcopenic patients. Sarcopenia was not significantly associated with shorter survival after completing bladder preservation therapy in either study. For complication rates of bladder preservation therapy, one study showed equivalent complication rates of consolidative partial cystectomy between sarcopenic and non-sarcopenic patients. In addition, in another small series of trimodal therapy, sarcopenic patients showed a higher rate of complications of trimodal therapy compared with non-sarcopenic patients.

CONCLUSIONS

According to the result of our literature review, sarcopenia would not affect responses to trimodal therapy and prognosis in MIBC patients treated with bladder preservation therapy. Although the effect of sarcopenia on complication rates of bladder preservation therapy is inconclusive due to limited evidence, bladder preservation therapy could be a viable alternative option in carefully selected MIBC patients regardless of the presence of sarcopenia.

Optimisation of Radiation Therapy in Bladder Preservation Therapy for Patients With Clinical Stage T2N0M0 Bladder Cancer

AIMS

A novel bladder preservation therapy, the OMC (Osaka Medical College) regimen, which combines radiation therapy with balloon-occluded arterial infusion of anticancer agents, is a treatment option for patients with muscle-invasive bladder cancer (MIBC). We retrospectively analysed the effects of changes in radiation dose and irradiation field on treatment efficacy and adverse events.The purpose of this study is to use the results of this study to help determine a course of radiation therapy for bladder preservation therapy of cT2N0M0 MIBC.

MATERIALS AND METHODS

We examined 352 patients with clinical stage T2N0M0 (cT2N0M0) MIBC classified into the following groups based on the irradiation method: group A, the whole pelvis (50 Gy/25 fractions) + local bladder (10 Gy/5 fractions); group B, the small pelvis (50 Gy/25 fractions) + local bladder (10 Gy/5 fractions); group C, the whole pelvis (40 Gy/20 fractions) + local bladder (10 Gy/5 fractions).

RESULTS

The complete response rate, 3-year overall survival and progression-free survival rates in group A were 92.9%, 94.9% and 82.1%, respectively; in group B were 87.2%, 86.7% and 76.7%, respectively; and in group C were 95.2%, 92.6% and 71.1%, respectively. No significant differences between the groups were noted. The incidence of ≥grade 3 urinary tract and gastrointestinal toxicities were not significantly different among the groups (group A: 7.8%, 1.7%; B, 11.1%, 0%; C, 7.1%, 1.8%, respectively). The 3-year progression-free rates of the common iliac lymph node (CILN) region in patients who received whole-pelvis and small-pelvis irradiation were 99.0 and 89.0% (P < 0.01), respectively, with the latter group having significantly high lymph node recurrence in the CILN region.

CONCLUSIONS

Our findings showed that the optimal radiation therapy for patients with cT2N0M0 MIBC undergoing the OMC regimen is whole-pelvis irradiation including the CILN region, with a total dose of 50 Gy/25 fractions.

Partial cystectomy for muscle-invasive bladder cancer: a review of the literature

The radical cystectomy (RC) for muscle-invasive bladder cancer is one of the most morbid and complex urologic procedures performed today. To avoid these complications, the partial cystectomy (PC) has been offered as an alternative in carefully selected patients as a means of achieving equal oncologic efficacy with less morbidity. Selection criteria should include solitary tumors without concomitant carcinoma in situ (CIS) and amenable to resection with 1–2 cm margins in a normally functioning bladder. In addition to the standard work-up, random bladder and prostatic biopsies may be performed. The PC can be performed through an open, laparoscopic, or robot-assisted approach, each with acceptable outcomes. A number of techniques have been developed to identify and resect the tumor completely with negative margins, while preventing tumor spillage within the abdomen. While there are no randomized trials, single institution series have demonstrated acceptable oncologic outcomes in appropriately selected patients. Therefore, offering PC in the appropriate candidate, including those patients who do not accept or are unfit for the associated morbidity of a RC, represents an acceptable alternative.

Bladder-sparing protocols in the treatment of muscle-invasive bladder cancer

Bladder-sparing protocols (BSP) have been gaining widespread popularity as an attractive alternative to radical cystectomy (RC) for muscle-invasive bladder cancer. Unimodal therapies are inferior to multimodal regimens. The most promising regimen is trimodal therapy (TMT), which is a combination of maximal transurethral resection of bladder tumor (TURBT), radiotherapy, and chemotherapy. In appropriately selected patients (low volume unifocal T2 disease, complete TURBT, no hydronephrosis and no carcinoma-in-situ), comparable oncological outcomes to RC have been reported in large retrospective studies, with a potential improvement in overall quality of life (QOL). TMT also offers the possibility for definitive therapy for patients who are not surgically fit to undergo RC. Routine biopsy of previous tumor resection is recommended to assess response. Prompt salvage RC is required in non-responders and for recurrent muscle-invasive disease, while non-muscle-invasive recurrence can be managed conservatively with TURBT +/- intravesical BCG. Long-term follow-up consisting of routine cystoscopy, urine cytology, and cross-section imaging is required. Further studies are warranted to better define the role of neoadjuvant or adjuvant chemotherapy in the setting of TMT. Finally, future research on predictive markers of response to TMT and on the integration of immunotherapy in bladder sparing protocols is ongoing and is highly promising.

Bladder preservation therapy for muscle invasive bladder cancer: the past, present and future

Radical cystectomy is the gold standard treatment for muscle invasive bladder cancer, but some patients have medically inoperable disease or refuse cystectomy to preserve their bladder function. Bladder preservation therapy with transurethral resection of the bladder tumor and concurrent chemoradiotherapy, known as trimodal treatment, is regarded to be a curative-intent alternative to radical cystectomy for patients with muscle invasive bladder cancer during the past decade. After the development of immune checkpoint inhibitors, a world-changing breakthrough occurred in the field of metastatic urothelial carcinoma and many clinical trials have been conducted against non-muscle invasive bladder cancer. Interestingly, preclinical and clinical studies against other malignancies have shown that immune checkpoint inhibitors interact with the radiation-induced immune reaction. As half of the patients with muscle invasive bladder cancer are elderly, and some have renal dysfunction, not only as comorbidity but also because of hydronephrosis caused by their tumors, immune checkpoint inhibitors are expected to become part of a new therapeutic approach for combination treatment with radiotherapy. Accordingly, clinical trials testing immune checkpoint inhibitors have been initiated to preserve bladder for muscle invasive bladder cancer patients using radiation and immune checkpoint inhibitors with/without chemotherapy. The objective of this review is to summarize the evidence of trimodal therapy for muscle invasive bladder cancer during the past decade and to discuss the future directions of bladder preservation therapy in immuno-oncology era.

Radiation dose in neoadjuvant chemoradiation therapy for esophageal cancer: patterns of care and outcomes from the National Cancer Data Base

Background

Neoadjuvant chemoradiotherapy (CRT) for locally advanced esophageal cancer (EC) may utilize a wide variety of RT doses, without clear consensus to date. This study evaluated national practice patterns between lower dose (LD) (40-41.4 Gy) or higher dose (HD) (50-50.4 Gy) therapy, in addition to differences in survival and postoperative events.

Methods

The National Cancer Data Base (NCDB) was queried [2004-2013] for patients with newly-diagnosed cT1a-T4aN0/N+M0 EC that received neoadjuvant CRT followed by esophagectomy. Multivariable logistic regression determined factors predictive of receiving LD RT. Kaplan-Meier analysis evaluated overall survival (OS), and Cox proportional hazards modeling determined variables associated with OS. Propensity score matching assessed groups in a balanced manner while reducing indication biases.

Results

Altogether, 5,025 patients met inclusion criteria; 257 (5%) received LD RT, while 4,768 (95%) received HD RT. LD RT was more likely delivered at academic centers (P=0.038), in more recent years (2009-2013, P=0.011), and to squamous cell carcinomas (P=0.001). HD RT tended to be administered with higher T stage as well as node-positive disease (P<0.05). The median OS in the LD and HD cohorts was 39.0 vs. 35.6 months (P=0.072), and 39.0 vs. 42.7 months after propensity matching (P=0.812). Dose did not independently correlate with OS on multivariate analysis (P=0.069), but treatment at academic centers correlated with improved OS (P=0.028). There were no differences between groups in the rates of 30-day readmission (P=0.182), 30-day mortality (P=0.314), or length of postoperative hospital stay (P=0.665), but the LD group experienced lower 90-day mortality (P=0.007).

Conclusions

Although neoadjuvant LD CRT has been underutilized for EC in the United States, it is rising in more recent years. Dose did not significantly impact survival before or after propensity matching, nor did it independently predict for survival. Treatment at academic facilities independently correlated with higher survival, which has implications for patient counseling.