Use of bacillus Calmette-Guérin in stage T1 bladder cancer: Long-term observation of a population-based cohort.

Objective: The aim of this study was to analyse the rate of use of bacillus Calmette-Guérin (BCG) at a population-based level, and the overall mortality and bladder cancer mortality due to stage T1 bladder cancer in a national, population-based register.
Materials and Methods: In total, 3758 patients with primary stage T1 bladder cancer, registered in the Swedish Bladder Cancer Register between 1997 and 2006, were included. Age, gender, tumour grade and primary treatment in the first 3-6 months were registered. High-volume hospitals registered 10 or more T1 tumours per year. Date and cause of death were obtained from the National Board of Health and Welfare Cause of Death Register.
Results: BCG was given to 896 patients (24%). The use of BCG increased from 18% between 1997 and 2000, to 24% between 2001 and 2003, and to 31% between 2004 and 2006. BCG was given more often to patients with G3 tumours, patients younger than 75 years and patients attending high-volume hospitals. BCG treatment, grade 2 tumours and patient age younger than 75 years were associated with lower mortality due to bladder cancer. Hospital volume, gender and year of diagnosis were not related to bladder cancer mortality. However, selection factors might have affected the results since comorbidity, number of tumours and tumour size were unknown.
Conclusions: Intravesical BCG is underused at a population-based level in stage T1 bladder cancer in Sweden, particularly in patients 75 years or older, and in those treated at low-volume hospitals. BCG should be offered more frequently to patients with stage T1 bladder cancer in Sweden.