ASSOCIATION OF IN-VITRO GROWTH-POTENTIAL OF URINARY EXFOLIATED CELLS WITH TUMOR-LOCALIZATION AND INTRALUMINAL RECURRENCE RATES OF UROTHELIAL CANCERS

Purpose: One problem in the treatment of urothelial cancers, in partic ular of upper urinary tract cancers, is multifocal synchronous and/or metachronous tumor development in the heterotopic urothelium. We inves tigated the abilities of exfoliated cells in the urine of patients wit h urothelial cancers to colonize and proliferate in vitro. Materials a nd Methods: Short-term cultures of 129 urine samples obtained from pat ients with urothelial cancers and 53 samples from healthy volunteers w ere compared as to the growth potential of urinary-exfoliated cells an d clinico-pathological features, in particular tumor localization and evidence of intraluminal tumor recurrence. Results: Primary cell outgr owth occurred in 112 (86.8%) of the 129 cell cultures from the patient s and in 29 (54.7%) of the 53 from the healthy volunteers ip <0.0001). ''Sufficient cell growth'' (more than 10(5) cells per flask) was obta ined for 77 (59.7%) of the 129 cultures from patients and 7 (13.2%) of the 53 from the healthy volunteers (p <0.001). in terms of tumor loca lization, the rate of sufficient cell growth was significantly higher for patients with upper urinary tract tumor (21/25, 84.0%) than for th ose with bladder tumor (56/104, 53.8%) (p = 0.0062). Proportional haza rd regression analysis showed that only the growth potential of the ur inary-exfoliated cells was significantly predictive of intravesical tu mor recurrence in patients with superficial bladder tumors (p = 0.011) . Conclusions: The potentials for the colonization and proliferation o f urinary-exfoliated cells are associated with intraluminal multifocal tumor recurrence of urothelial cancers.