New experimental models for the in vitro reconstitution of human bladder mucosa.

This study describes two experimental models for the in vitro reconstitution of the human bladder mucosa (neo-bladder): human urothelial stabilized cell lines were cultured on three-dimensional matrices, collagen or platelet-fibrin gels, containing murine fibroblast 3T3-J2 cells. Low-density seeding (2x10(4) cells/ml) of both normal (TCA-48) and neoplastic cell lines (TCA-47) on collagen matrix gave rise to isolated papillar colonies, while high-density seeding (3.75x10(6) cells/ml) led to the formation of wide pluristratified epithelial sheets, resembling the normal transitional epithelium. In contrast, high-density seeding (5x10(5) cells/ml) on platelet-fibrin matrix did not allow the formation of epithelial sheets: only isolated voluminous colonies of normal TCA-48 cells, and sparse and small colonies of neoplastic TCA-47 could be observed. Growth assays and cytotoxicity reduction tests showed that the growth inhibitory effect of platelet-fibrin gel on urothelial cells was probably due to the aspecific activation of the complement contained in the plasmatic fraction, whose precipitation forms fibrin-glue. Collectively, these findings allow us to draw the following conclusions: i) neobladders obtained by culturing urothelial cells on collagen matrix reproduce normal bladder mucosa and could be utilized in pharmacological studies; and ii) platelet-fibrin gels, that specifically inhibit neoplastic urothelial cell growth, could be used as scaffolds in surgical bladder reconstitution.

[Prostatic tumor: how many biopsies?]. / Tumore prostatico: quante biopsie?

INTRODUCTION: Ultrasound-guided prostatic biopsy is usually performed by sextants according to Hodge, but the authors feel that 6 biopsies are insufficient. It has been suggested that the number of prostatic biopsies be increased and the mapped areas extended, but this causes discomfort to patients and increases effective costs. The authors suggest repetition of biopsies in "risk" cases, routinely selecting patients taking into account the best cost-benefit ratio. MATERIALS AND METHODS: From January 2000 to December 2001, 682 first series biopsies were performed on as many patients. A Stamey modified sextant technique was used: 6 biopsies, 3 on each side carried out more posterolaterally than the original technique. The biopsy procedure was repeated within 4 months in 11 patients with high risk clinical parameters (PSA > 10 or high PSA and prostatic nodule). During the period of observation, 25 patients had over 0.75 ng/year increase in their PSA and so biopsies were repeated. RESULTS: After the first biopsy series, 277 were positive. Of the 11 repeated biopsies, 3 were positive. Of the 25 patients with altered PSA velocity, 9 were positive. DISCUSSION AND CONCLUSIONS: It has been shown that only 10-12% of biopsies are false negative in the sextant biopsy series when taken posterolaterally. The techniques that increase the number of biopsies have around 3-5% false negatives, but this involves more discomfort for the patient, local anaesthesia and a possible increase in complications. The procedure whereby biopsies were only repeated in patients with high risk clinical elements, saved 3852 biopsies from being carried out, with an economic saving (just on the histological exam that was not carried out) assessed at 59.681,80 Euro (115,560,000 Lire) for our Local Health Service.