What is the Optimal Dose, Fractionation and Volume for Bladder Radiotherapy?

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.

Implications for pelvic lymph node irradiation in definitive chemoradiotherapy of node negative muscle invasive bladder cancer based on predictive factors of clinicopathologic discrepancy

PURPOSE

To identify pre-surgical imaging predictive value and factors associated with the clinicopathologic discrepancy for implication of definitive pelvic radiotherapy in clinically node-negative bladder cancer.

METHOD

The documented data of bladder cancer patients who underwent radical cystectomy plus pelvic lymphadenectomy were collected retrospectively. Patients' characteristics, last imaging, pathology reports, disease-specific survival and overall survival were retrieved.

RESULTS

From 142 patients, pre-surgical imaging had a sensitivity of 76.4%, specificity of 73.7%, positive predictive value (PPV) of 94.9%, and negative predictive value (NPV) of 32.6% (p value < 0.0001) for detection of muscle invasion. Also, for detection of positive lymph nodes, imaging had a sensitivity of 31.8%, specificity of 85.7%, PPV of 50%, and NPV of 73.7% (p value: 0.022). 44.4% of study population were upstaged after surgery (24.6% associated with N-upstaging) and 18.3% were downstaged (12% associated with N-downstaging). Receipt of neoadjuvant chemotherapy and T-stage were not correlated with N-upstaging. On multivariate analysis, lymphovascular invasion (LVI) maintained its significance for independent prediction of upstaging (OR 3.3, 95% CI 1.5-7.5, p value: 0.004) and inversely with downstaging (OR 0.34, 95% CI 0.12-0.96, p value: 0.04). Older age (OR 1.03, 95% CI 1.0-1.05, p value 0.047), positive margins (OR 2.1, 95% CI 1.2-3.8, p value 0.011), presence of LVI (OR 2.5, 95% CI 1.4-4.7, p value 0.003), perineural invasion (OR 2.0, 95% CI 1.2-3.4, p value 0.013), and lymph node ratio (OR 1.011, 95% CI 1.001-1.021, p value 0.03) were associated with worse survival. Also, N-upstaging independently predicted a worse survival after controlling for surgical pathology stage (OR 2.3, 95% CI 1.2-4.5, p value 0.011).

CONCLUSIONS

The optimal target volume in definitive chemoradiotherapy of node-negative bladder cancer patients remains to be established. Since then, customizing the treatment is considered especially for positive LVI in TURBT specimen.

Bladder preservation in older adults with muscle-invasive bladder cancer: A retrospective study with concurrent chemotherapy and twice-daily hypofractionated radiotherapy schedule

BACKGROUND

Bladder cancer occurs mainly in older adults and surgery is not always possible when there are geriatric conditions and comorbidities. Trimodal treatment (TMT) combining trans-urethral resection of bladder tumour (TURBT) followed by concurrent chemoradiation (CRT) would be a curative alternative in such patients.

METHODS

All consecutive patients 75 years of age and older with non-metastatic muscle-invasive bladder cancer (MIBC) treated with TMT by Georges Pompidou European Hospital team were retrospectively analysed. Induction CRT combined hypofractionated twice-daily radiotherapy targeting bladder and pelvis to a total dose of 24 Gy (Gy) with concurrent platinum salt and 5-fluorouracil. Consolidation CRT to a total dose of 44 Gy was proposed to patients with biopsy-proven complete response after induction phase and those with persistent tumour underwent salvage cystectomy. We assessed using Kaplan-Meier method overall survival (OS), cancer specific survival (CSS), invasive recurrence-free survival (IRFS), metastasis-free survival (MFS), survival with bladder preserved (SBP), and toxicities. With a Cox model for OS and the Fine Gray method of competing risk for secondary endpoints, we analysed in univariate (u) and multivariate (m) analysis the impact of tumour characteristics and patient profiles: gender, age, age-adjusted Charlson comorbidity index, polypharmacy, and malnutrition.

RESULTS

From 1988 to 2017, 85 patients were included. After induction, complete response rate was 83.5%. With a median follow-up of 63 months, 5 year-OS, CSS, IRFS, MFS and SBP were 61.0%, 77.6%, 71%, 82.9%, and 70.2% respectively. A persistent tumour after induction impacted SBP (SHRm 3.61; p = 0.004), CSS (SHRm 3.27; p = 0.023), and MFS (SHRm 3.68; p = 0.018). Late grade 3 urinary and gastrointestinal toxicities were 3.5% and 1.2%.

CONCLUSION

We report here the largest series of bladder preservation over 75 years in a curative intent. Outcomes and tolerance in selected older adults compared favourably with surgical series and with CRT studies using classical fractionation.