All patients will have their bladder tumour removed using a diode laser. The treatment will take place in the outpatient department (OPD) without any pain treatment. Biopsy from the tumour will be obtained before the procedure. If the biopsy shows low grade non-invasive bladder tumour, flexible cystoscopy will be repeated one month later in the OPD. At both procedures biopsy will be taken from the laser treated area.