ABSTRACT
CIS of the bladder is a high risk superficial bladder cancer, becoming muscle invasive in 60-80% of the cases in 5 years and accounting for 39% of patient death. For the diagnosis of CIS, the specifity of the cytology ranges between 66% and 83%, and the detection during cystoscopy may be challenging. Although intravesical BCG is the most successful bladder sparing option for treatment, 30% to 40% of the cases do not respond to this treatment and finally progress to muscle invasive tumors. On the other hand, immediate radical cystectomy provides patients a better survival rate, but has higher morbidity. There are promising results in new bladder sparing treatments that need approval by larger numbers of studies. In this article, the challenges in diagnosis and treatment and also new treatment modalities are summarised.