657 BLADDER AUGMENTATION BY TISSUE ENGINEERING USING MULTIPLE SCAFFOLDS IN ONE BLADDER AND GROWTH FACTORS IN A PORCINE MODEL

656

Randomized phase III trial comparing adjuvant paclitaxel/gemcitabine/cisplatin (PGC) to observation in patients with resected invasive bladder cancer: Results of the SOGUG-GUO-AEU 99/01 trial

Solsona, E.1, Paz-Ares, L.2, Fernandez, J.M.3, Hevia, M.3, Orsola, A.4, Morote, J.4, Bellmunt, J.5, De La Rosa, F.1, Llorente, C.6, Donas, Jl.6, Guillem, V.7, Cozar, J.M.8, Ballesteros, P.9, Javaloyas, J.9, Carbonero, J.1, Burgues, J.P.10, Rodríguez Molina, J.11, Gutierrez, J.L.12, García, D.13 1 Institute Valenciano de Oncologia, Dept. of Urology, Valencia, Spain, 2Hospital Virgen del Rocio, Dept. of Urology, Seville, Spain, 3Hospital General de Asturias, Dept. of Urology, Oviedo, Spain, 4Hospital de la Vall D´Hebron, Dept. of Urology, Barcelona, Spain, 5Hospital del Mar, Dept. of Oncology, Barcelona, Spain, 6Hospital de Alcorcón, Dept. of Urology, Alcorcón, Spain, 7Institute Valenciano de Oncologia, Dept. of Oncology, Valencia, Spain, 8Hospital Virgen del las Nieves, Dept. of Urology, Granada, Spain, 9Hospital Clinic, Dept. of Urology, Valencia, Spain, 10Hospital de Son Dureta, Dept. of Urology, Palma, Spain, 11Hospital Clínico San Carlos, Dept. of Urology, Madrid, Spain, 12Hospital de Valdecilla, Dept. of Urology, Santander, Spain, 13 Hospital de Sabadell, Dept. of Urology, Sabadell, Spain Introduction & Objectives: Around 70% of patients with invasive bladder cancer who show adverse pathological features after cystectomy (CTx) will die of cancer, most of the recurrences being systemic. We have studied in a randomized phase III trial the role of 4 courses of the PGC triplet as compared to observation in this clinical setting. Materials & Methods: Eligibility criteria included: (1) resected high-risk muscle invasive bladder carcinoma (pT3-and/or pN+),(2) ECOG PS 0-1, (3) adequate renal function (CrCl > 50 ml/min) (4) < 8 weeks post-CTx, (5) no relevant comorbidities, and (6) signed informed consent. Eligible patients were assigned to observation or 4 courses of PGC ( P 80 mg/m2 d1 and 8, G 1000mg/m2 d1 and 8 and C 70 mg/m2 d1) q21 days. The primary objective was overall survival (OS). Results: The study was open in July 2000 and prematurely closed due to poor recruitment in July 2007, with 142 patients randomized (74 observation and to 68 to PGC treatment). Baseline characteristics were well balanced among study arms. Median age was 63 yrs, pT3-4NO: 44%, any pTN+: 56%, PS 0: 59% median time CTx-randomization: 48 days (14-91). Complications rate related to surgery, grade 3-4 (Clavien) was of 19.7% in 12.6% patients. In the PGC arm 76% of pts completed all 4 courses of therapy. Main Gr 3-4 toxicities rate was of 26.4% in 20.5% of patients with one toxic death (sepsis). Positive margins were observed in10.5% of specimens and the mean number of nodes retrieved was 10.9 (1-28) although in 6.6% of patients lymphadenectomy was not performed or there are no information. At a median follow up of 30 months (range 1-95), 69 patients have died (45 in control arm and 24 in PGC arm) OS (ITT population) was significantly prolonged in the PCG arm (median NR; 5yr OS: 60%) compared to observation (median 26m; 5yr OS: 31%) (p<0.0002) were also superior in the PGC arm. Conclusions: The results of this study strongly suggest that adjuvant PGC improves. OS and DFS following CTx in high risk invasive bladder cancer. As the study was prematurely closed, the power for firm conclusions is however limited.

Poster Session 55 BASIC SCIENCE AND TISSUE ENGINEERING Sunday, 20 March, 15.45-17.15, Hall E1

657

Bladder augmentation by tissue engineering using multiple scaffolds in one bladder and growth factors in a porcine model

Roelofs L.A.J.1, Kortmann B.B.M.1, De Gier R.P.E.1, Farag F.1, Tiemessen T.M.1, Oosterwijk E.1, Versteeg E.M.M.2, Daamen W.F.2, Van Kuppevelt T.H.2, Geutjes P.J.1, Feitz W.F.J.1 1 Radboud University Nijmegen Medical Centre, Dept. of Urology, Nijmegen, The Netherlands, 2Radboud University Nijmegen Medical Centre, Dept. of Biochemistry, Nijmegen, The Netherlands Introduction & Objectives: Tissue engineering aims to develop alternatives for the current technique of bladder augmentation. When using a large acellular scaffold central necrosis may occur due to the lack of cell ingrowth and blood vessel development. In order to overcome this problem we studied the concept of implanting multiple scaffolds in one bladder instead of 1 large construct. Furthermore, we studied the use of growth factors to enhance cell growth in the scaffold . Materials & Methods: Three different scaffolds of 3 cm Ø were investigated: 1) crosslinked type I collagen scaffold (Col-X) 2) Col-X incorporated with heparin (Col-X-Hep) 3) Col-X-Hep with 3 growth factors (VEGF, FGF-2 and EGF) (ColX-Hep-GF), which we compared to a ‘sham-operated’ group. In total 13 pigs were operated. Three pigs were operated in each group and 3 scaffolds were implanted, or 3 lesions were sutured without implant (Sham group). Urodynamics were performed before operation. After 3 months functional (cystogram and

Eur Urol Suppl 2011;10(2):212

urodynamics) and histological evaluation (HE, CK7, vimentin, α-sma, desmin, smoothelin) was performed on the bladders. Results: Twelve of 13 operated pigs fulfilled the entire experiment, one pig died because of urine leakage and peritonitis. Survival rate was 92%. In all animals the cystograms were normal. Urodynamic studies did not show differences in compliance or capacity between all groups, due to the very high compliance and capacity of porcine bladders. Histological evaluation revealed a normal urothelial layer and good neovascularisation in all groups. Smooth muscle ingrowth was enhanced in the Col-X-Hep-GF group. No signs of central maldevelopment were seen. The scaffolds were almost fully degraded, some remnants were visible in the Col-X-Hep group. Conclusions: We showed the feasibility of implanting multiple scaffolds in one bladder in order to improve its capacity. Incorporation of heparin with growth factors improved ingrowth of muscle cells.

658

Porcine extracellular matrix scaffolds in reconstructive urology: A comparative study of their biomechanical properties

Davis N.F.1, Callanan A.2, McGuire B.B.1, Flood H.D.1, McGloughlin T.M.2 1 Mid-Western Regional Hospital, Dept. of Urology, Limerick, Ireland, 2University of Limerick, Centre for Applied Biomedical Engineering Research, Limerick, Ireland Introduction & Objectives: Functional reconstruction of the human urinary bladder has been attempted by replacing defective bladder tissue with xenogenic tissueengineered extracellular matrix (ECM) scaffolds. However, experimental studies that demonstrate the effects of implanted ECMs on important biomechanical properties such as bladder capacity (BC) and compliance (C) are lacking. In the current study the effects of ECM scaffold surface area (SA) on TBC and C was assessed in an ovine model (n=7). Materials & Methods: BC and C were measured at incremental pressure (P) increases prior to performing a 3x3cm (9cm2) partial cystectomy defect in each ovine model. Equal sized 3x3cm (9cm2) and larger 6x6cm (36cm2) urinary bladder matrix (UBM) scaffolds of porcine origin replaced the 3x3cm cystectomy defect and BC and C were re-recorded for comparative analysis with native values. Results: BC decreased by 39.6% ± 0.005% (122.9ml ± 15ml, p<0.05) and C by 38.9% ± 0.51%, (∆P=0-5mmHg, p<0.05) in ovine bladders reconstructed with 3x3cm UBM scaffolds compared to their native values (Table 1). It was also found that BC and C improved by 25.6% ± 0.64% (64.2ml ± 8.8ml, p>0.05) and 31.6% ± 0.7% (∆P=0-5mmHg) respectively in the 6x6cm UBM scaffold group compared to the 3x3cm UBM scaffold group, however these values remained lower than the native group by 18 ± 1.6% (58.7 ± 18ml). Native

3x3cm UBM scaffold

6x6cm UBM scaffold

ΔV (ml)

223.2 ± 60.9

136 ± 34.3

179.2 ± 42.4

ΔP (mmHg)

0-5

0-5

0-5

C (ml/mmHg)

44.6 ±12.2

27.24 ± 14.3

35.84 ± 13.1

Table 1: Comparative assessment of compliance (C) in each experimental group at physiological pressures (ΔP=0-5mmHg). C was measured by dividing volume (ΔV) changes by their relative pressure (P) changes (C=ΔV/ΔP). Conclusions: ECM scaffolds are biomechanically limited for bladder reconstructive purposes, however an increase in ECM scaffold SA relative to its intended defect may lead to improved biomechanical properties

659

Promising in vitro data for a new collagenbased urothelial implant for reconstructive surgery of the lower urinary tract

Feil G.1, Maurer S.1, Just L.2, Krug J.1, Kohler K.3, Stenzl A.1, Sievert K.D.1 1 Eberhard Karls University, Dept. of Urology, Tübingen, Germany, 2Eberhard Karls University, Institute of Anatomy, Tübingen, Germany, 3Eberhard Karls University, Center For Regenerative Biology and Regenerative Medicine, Tübingen, Germany Introduction & Objectives: Tissue engineering is an auspicious technique for reconstructive purposes of the lower urinary tract, especially in patients for whom autologous grafts are not available. In vitro engineering of lower urinary tract tissue equivalents requires biomaterials as cell carriers that should conduct primary cell attachment and cell proliferation. The aim of this study was to investigate a new highly standardized, biocompatible, factory-made bovine collagen I-based cell carrier (bovCCC) for its suitability as carrier matrix for human urothelial cells (HUCs) compared to a commercially available equine collagen-based cell carrier (equCCC). Materials & Methods: Ureter tissue specimens were obtained from adult patients undergoing open tumour surgery according to the ethics committee approval. HUCs were isolated and labelled with the fluorescent cell linker PKH26. Two HUC lines each were seeded on bovCCC and equCCC and cultivated in a feeder cell-free and serum-free cell culture system. As controls, HUCs were seeded on standard plastic surface. Cell adherence was indirectly ascertained by counting non-adherent cells in the culture supernatant. Metabolic activity of HUCs seeded on the cell carriers was analysed with the WST-1 assay. Stratification of urothelial