Abstract
Purpose
Many muscle-invasive bladder cancers are hypoxic, which limits the efficacy of radiation therapy. Hypoxia modification using carbogen and nicotinamide has been tested in a phase 3 trial, Bladder Carbogen Nicotinamide. We present mature follow-up data with biomarker predictions of outcomes.
Methods and Materials
Bladder Carbogen Nicotinamide is a prospective, phase 3, multicenter, randomized, 2-arm, nonblinded clinical trial. Participants were randomized to receive radical radiation therapy (RT; control arm) alone or with the addition of carbogen (98% O2; 2% CO2) and nicotinamide (CON). Patients with muscle-invasive or high-grade non–muscle invasive bladder cancer were included. Tumor tissue was collected at entry and was analyzed for tumor necrosis, hypoxia (24-gene signature), and basal and luminal tumor molecular subtypes. Overall survival (OS) and disease-free survival and relationships with biomarker status outcomes are analyzed using multivariable Cox regression and log-rank analysis.
Results
We analyzed 333 patients with a median follow-up of 10.3 years. The 10-year OS rates were 30% (95% confidence interval [CI], 0.23-0.39) in RT + CON patients and 24% (95% CI, 0.18-0.33) in the RT-alone patients (hazard ratio [HR], 0.80; 95% CI, 0.61-1.04; P = .08). The greatest benefit from CON was seen in patients with tumor necrosis (n = 79; 5-year OS, 53% vs. 33% in patients without tumor necrosis; HR, 0.59; 95% CI, 0.36-0.99; P = .04). Cases with a high hypoxia gene score (n = 75) had a 5-year OS rate of 51%, compared to 34% for a low score (HR, 0.64; 95% CI, 0.38-1.08; P = .09); those with the basal molecular subtype (n = 70) had a 5-year OS rate of 58%, compared to 38% for those with the luminal subtype (HR, 0.58; 95% CI, 0.32-1.06; P = .08).
Conclusions
Although the improvement in long-term OS in the whole population is not statistically significant, patients selected by necrosis and high hypoxia gene score benefitted from hypoxia modification.
Many muscle-invasive bladder cancers are hypoxic, which limits the efficacy of radiation therapy. Hypoxia modification using carbogen and nicotinamide has been tested in a phase 3 trial, Bladder Carbogen Nicotinamide. We present mature follow-up data with biomarker predictions of outcomes.
Methods and Materials
Bladder Carbogen Nicotinamide is a prospective, phase 3, multicenter, randomized, 2-arm, nonblinded clinical trial. Participants were randomized to receive radical radiation therapy (RT; control arm) alone or with the addition of carbogen (98% O2; 2% CO2) and nicotinamide (CON). Patients with muscle-invasive or high-grade non–muscle invasive bladder cancer were included. Tumor tissue was collected at entry and was analyzed for tumor necrosis, hypoxia (24-gene signature), and basal and luminal tumor molecular subtypes. Overall survival (OS) and disease-free survival and relationships with biomarker status outcomes are analyzed using multivariable Cox regression and log-rank analysis.
Results
We analyzed 333 patients with a median follow-up of 10.3 years. The 10-year OS rates were 30% (95% confidence interval [CI], 0.23-0.39) in RT + CON patients and 24% (95% CI, 0.18-0.33) in the RT-alone patients (hazard ratio [HR], 0.80; 95% CI, 0.61-1.04; P = .08). The greatest benefit from CON was seen in patients with tumor necrosis (n = 79; 5-year OS, 53% vs. 33% in patients without tumor necrosis; HR, 0.59; 95% CI, 0.36-0.99; P = .04). Cases with a high hypoxia gene score (n = 75) had a 5-year OS rate of 51%, compared to 34% for a low score (HR, 0.64; 95% CI, 0.38-1.08; P = .09); those with the basal molecular subtype (n = 70) had a 5-year OS rate of 58%, compared to 38% for those with the luminal subtype (HR, 0.58; 95% CI, 0.32-1.06; P = .08).
Conclusions
Although the improvement in long-term OS in the whole population is not statistically significant, patients selected by necrosis and high hypoxia gene score benefitted from hypoxia modification.
| Original language | English |
|---|---|
| Journal | International Journal of Radiation: Oncology - Biology - Physics |
| DOIs | |
| Publication status | Published - 6 Mar 2021 |
Research Beacons, Institutes and Platforms
- Manchester Cancer Research Centre
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Dive into the research topics of 'Long-Term Outcomes of Radical Radiation Therapy with Hypoxia Modification with Biomarker Discovery for Stratification: 10-Year Update of the BCON (Bladder Carbogen Nicotinamide) Phase 3 Randomized Trial (ISRCTN45938399)'. Together they form a unique fingerprint.Impacts
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Identifying molecular markers for improving the outcomes of radiotherapy and leading to spin out company Mantra Diagnostics
West, C. (Corresponding participant), Choudhury, A. (Participant), Hoskin, P. (Participant) & Smith, T. (Participant)
Impact: Health and wellbeing, Economic