Recurrent Non-Muscle-Invasive Bladder Cancer

Sammanfattning: A characteristic feature of non-muscle-invasive bladder cancer (NMIBC) is the high risk of recurrent disease after primary treatment. Although only a minority of cases eventually progress to a life-threatening muscle-invasive tumour, it is necessary to conduct long-term follow-up with repeated cystoscopies. In addition to the negative mental and physical impact that this has on the patient, the examinations and the treatments of recurrence, impose an economic burden on the health care system. This thesis deals with various aspects of recurrent NMIBC. Paper I describes the present study of the genetic relationship between primary and recurrent tumours which revealed that in some cases there are fewer genetic aberrations in the latter than in the former. This finding contradicts the existance of a direct monoclonal relationsship between a primary and a recurrent tumour, although those lesions do show remarkably similar gene expression, which suggests that both are derived from a common progenitor cell. Paper II reports findings demonstrating that the voided urine marker, UroVysion® assay is too insensitive to replace cystoscopy in the follow-up of NMIBC patients. The results discussed in Paper III imply that only patients at low risk of recurrence benefit from early intravesical chemotherapy, and this disagrees with the European Association of Urology, which currently recommends that this treatment be given to all patients with presumed NMIBC. Paper IV demonstrates that biopsies from non-tumourous areas of bladder and prostatic urethra offer only about 50% sensitivity for carcinoma in situ (CIS). Lastly, as outlined in Paper V, none of the gene markers studied by the tissue microarray technique (i.e, TP53, CDH1, FGFR3, COX2, EGFR) were found to be associated with recurrence, but concerns were raised regarding the reliability of this methodology.