Cold cup biopsies from 40 superficial bladder tumours were taken, fragmented, and left in culture. 3D-spheroids were obtained and transferred into a 24 multiwell dish containing (1) wells 1–3: 1mg/ml epirubicin (EPI); (2) 4–6: 1mg/ml EPI+0.5mg/ml VPM; (3) 7–9: 1mg/ml adriamycin (ADR); (4) 10–12: 1mg/ml thiotepa (THIO); (5) 13–15: 1mg/ml mitomycin C (MMC); (6) 16–18: 1mg/ml EPI+0.2mg/ml CIPRO; (7) 19–21: 0.2mg/ml CIPRO; (8) 22–24: controls. Sensitivity was calculated by using the trypan blue assay.

Evaluability of clinically relevant tests (G1–G2 lesions) was 84% (21 of 25 patients). MMC was the best agent (p<0.001) with mean sensitivity being 50%, followed by THIO (37%), EPI (7%), and ADR (3%). We found no significant difference (p=0.370) between CIPRO and the control, or between EPI+CIPRO and EPI alone (p=0.550). VPM markedly enhanced sensitivity to EPI compared with EPI alone (97% vs. 7%, p<0.001).

Our assay allows determining sensitivity to several drugs in superficial bladder tumours. It might be used in clinical practice to select the best drug for each patient. It also has experimental utility in investigating the effect of new drugs or combinations. VPM reverted resistance to EPI. CIPRO showed no effect on bladder tumour spheroids.

Juan Pablo Burgués, Luis Gómez, José Luis Pontones, César David Vera, Juan Fernando Jiménez-Cruz, Mariano Ozonas

Department of Urology, University Hospital Son Dureta, Palma de Mallorca, Spain

Department of Urology, University Hospital La Fe, Valencia, Spain

Accepted 17 October 2006 published online 30 October 2006.