ASCO GU 2019: Long-term Outcomes of Hypoxia Modification in Bladder Preservation: Update from BCON Trial

San Francisco, CA (UroToday.com) Radical treatment options for muscle-invasive bladder cancer are either cystectomy and trimodal treatment. Radiosensitization has been shown to improve patient outcomes, and it is the mainstay of trimodal therapy. Hypoxia is a poor prognostic factor in muscle-invasive bladder cancer and additional solid tumors. Hypoxia modification in combination with radiotherapy improves treatment response and patient outcomes in multiple cancer subsites.

In the BCON trial,  radiotherapy alone was compared to radiotherapy with carbogen and nicotinamide. Nicotinamide 40-60 mg/kg taken orally on a daily basis had been used for hypoxia modification, together with Carbogen (98% O2, 2% CO2. The primary outcome was local control. A total of 333 patients have been recruited with a median age of 74 years (51-90). All patient were T1G3 or T2-4aN0M0.

In this presentation Dr. Song, an update of this trial was presented with 301/321 (93.8%) of the patients being updated. The median follow-up was 10.3 years. The overall survival data demonstrated a clear benefit to the radiotherapy + hypoxia modification arm with a median overall survival of 55.5 vs 30.4 months, and a 5-year overall survival rate of 49.8% vs. 39.9%, p=0.05 (Figure 1).

Figure 1 – Overall survival:
Long term Outcomes of Hypoxia Modification in Bladder Preservation Update from BCON trial picture1

The relapse-free survival was also better in the radiotherapy + hypoxia modification arm, with a median of 152.7 vs. 61.5 months, and a 5-year recurrence-free survival of 59.4% vs. 50.7 (p=0.07) (Figure 2).

Figure 2 – Recurrence-free survival:
Long term Outcomes of Hypoxia Modification in Bladder Preservation Update from BCON trial picture 2

In conclusion, a sustained benefit of hypoxia modification in bladder preservation treatment was demonstrated. Improvement in overall survival and relapse-free survival was evident as well. Lastly, Dr. Song concluded that BCON is a standard of care, recommended in the NICE guidelines in the United Kingdom.

Presented by: Yee Pei Song, The University of Manchester, Manchester, United Kingdom

Written by: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre @GoldbergHanan at the 2019 American Society of Clinical Oncology Genitourinary Cancers Symposium, (ASCO GU) #GU19, February 14-16, 2019 - San Francisco, CA

Related Content: 
ASCO GU 2018: Use of Molecular Markers in Bladder Preservation Therapy