Small cell size circulating tumor cells predict the prognosis of high-risk non-muscle invasive bladder cancer patients

The study aimed to explore the distribution of circulating tumor cells (CTCs), circulating tumor endothelial cells (CTECs), and their subtypes in non-cancer and bladder cancer individuals, focusing on their prognostic value in high-risk non-muscle invasive bladder cancer (NMIBC). Researchers analyzed 59 fresh peripheral blood samples using subtraction enrichment and immunostaining fluorescence in situ hybridization (SE-iFISH). Samples were collected from healthy individuals (n = 18), patients with benign urinary conditions (n = 2), newly diagnosed bladder cancer patients (n = 20), and NMIBC patients after repeated transurethral resection of bladder tumor (R-TURBT) (n = 19). NMIBC patients had significantly higher total CTCs. In newly diagnosed bladder cancer patients, large CTCs constituted 58.8%. The most common karyotype was ≥ pentaploid CTCs (61.2%). In the non-cancer group, large CTCs constituted 83.0%, with ≥ pentaploid CTCs comprising 72.3% of aneuploid CTCs. For NMIBC patients after R-TURBT, those without recurrence had 16% small CTCs. Conversely, the recurrence group had 71% small CTCs, where tetraploid CTCs were predominant (40%). By performing logistic ridge repression, the ≥ pentaploid small CTC is noted as an important indicator of recurrence. The presence and proportion of small CTCs can serve as a prognostic marker in NMIBC patients following R-TURBT, potentially guiding patient management and surveillance strategies.