The long-term prognostic value of survivin expressing circulating tumor cells in patients with high-risk non-muscle invasive bladder cancer (NMIBC)

Objectives Long-term follow-up study to evaluate the impact on disease-free survival and cancer-specific survival of survivin expression in tissue and CTCs from T1G3 bladder cancer patients. Patients and methods The study was conducted using tumor tissue and blood samples from 54 patients with a primary diagnosis of T1G3 NMIBC. Survivin was evaluated by reverse transcription-polymerase chain reaction in tumor tissues. CTCs were isolated from blood by CELLection (TM) Dynabeads (Invitrogen, Carlsbad, CA, USA). Cells were lysed and cDNA was synthesized and analysed for the expression of CD45, CK8 and survivin. The endpoints of this long-termanalysis were disease-free survival, DFS and cancer-specific survival, CSS. Results Here, we report that, at 9 years of median follow-up, disease-free survival and cancer-specific survival are both significantly influenced by the expression of survivin in tumor tissue (p = 0.006), by the presence of CTCs (p < 0.0001) and by the expression of survivin in CTCs (p < 0.0001). Conclusions The statistically significant impact of survivin expressing CTCs on cancer-specific survival that we observed might be interpreted as the result of the persistence of a subpopulation of highlander cells in the blood of T1G3 bladder patients over time.