The aim of this study was to evaluate CT imaging in the post-operative follow-up and in the detection of recurrence after radical prostatectomy in cases of prostatic carcinoma. In over 500 patients undergoing radical prostatectomy for prostatic carcinoma, 22 cases with local recurrence were found. CT examinations of the pelvis were retrospectively evaluated in these patients. Local recurrence was detected by PSA uptake and confirmed by transrectal ultrasound (TRUS) in combination with guided biopsy. In 22 cases of confirmed local recurrence, positive results on CT were found in eight patients (36%) and negative results in nine patients (41%). In the remaining five cases (23%), no distinction could be made between scar and local recurrence. All cases definitively classified as recurrent tumour disease showed a soft tissue mass of 2 cm or more. CT sensitivity in local recurrence of prostatic carcinoma after surgery is low. Even in a very careful follow-up, the understaging would be up to 41%. In comparison, PSA, TRUS and needle biopsy are the methods of choice and are superior to CT imaging. Based on these results, there would be no reason for including pelvic CT examinations in the follow-up of prostatic carcinoma after radical prostatectomy.

Stereology and stochastic geometry can be used as auxiliary tools for diagnostic purposes in tumour pathology. Whether first-order parameters or stochastic-geometric functions are more important for the classification of the texture of biological tissues is not known. In the present study, volume and surface area per unit reference volume, the pair correlation function and the centred quadratic contact density function of epithelium were estimated in three case series of benign and malignant lesions of glandular tissues. The information provided by the latter functions was summarized by the total absolute areas between the estimated curves and their horizontal reference lines. These areas are considered as indicators of deviation of the tissue texture from a completely uncorrelated volume process and from the Boolean model with convex grains, respectively. We used both areas and the first-order parameters for the classification of cases using artificial neural networks (ANNs). Learning vector quantization and multilayer feedforward networks with backpropagation were applied as neural paradigms. Applications included distinction between mastopathy and mammary cancer (40 cases), between benign prostatic hyperplasia and prostatic cancer (70 cases) and between chronic pancreatitis and pancreatic cancer (60 cases). The same data sets were also classified with linear discriminant analysis. The stereological estimates in combination with ANNs or discriminant analysis provided high accuracy in the classification of individual cases. The question of which category of estimator is the most informative cannot be answered globally, but must be explored empirically for each specific data set. Using learning vector quantization, better results could often be obtained than by multilayer feedforward networks with backpropagation.

The purpose of the study was to simulate cystoscopy based on three-dimensional helical CT scan datasets in real-time in patients with tumours of the urinary bladder. A helical CT scan with double detector technology was carried out pre-operatively in 11 patients with histologically confirmed carcinoma of the urinary bladder and one patient with chronic cystitis. A non-enhanced scan was first performed, followed by an examination in the early phase of contrast medium enhancement. Further images were acquired after adequate filling of the bladder with contrast medium, approximately 30 min after injection. These data were transferred to a separate graphic computer workstation and reconstructed. The results were then compared with the cystoscopic and histopathological findings. All tumours of the urinary bladder identified at fibreoptic cystoscopy were shown on virtual cystoscopy. The best reconstruction results were obtained from data acquired 30 min after injection of contrast medium. The ureteric orifices were not visualized at virtual cystoscopy. These data lead us to conclude that, at present, virtual cystoscopy has not reached the quality of fibreoptic examination and remains restricted to use in specific cases, for example patients with urethral strictures.

Objective To identify chromosomal regions important for progression in clinically organ-con®ned prostate cancer, as the genetic changes underlying the development and progression of prostate cancer are poorly understood. Materials and methods Comparative genomic hybridization (CGH) was used to search for DNA sequence copy-number changes in a series of 50 primary organcon®ned prostate adenocarcinomas (pT2N0) removed by radical prostatectomy. Results CGH analysis indicated that 23 (46%) of the primary prostate adenocarcinomas showed chromosome alterations. The percentage of tumours with losses (38%) was higher than with gains (28%). Losses of 13q (24%), 8p (18%), 6q (10%), 16q (8%), 18q (6%) and 5q (6%) and gains of 17q (12%), 20q (12%), 9q (10%), 17p (8%) and 8q (6%) were the most frequent alterations. Ampli®cations were found at 8q24-qter. Minimal overlapping regions of loss, indicative of the presence of tumour-suppressor genes, were mapped to 13q21.1-q21.3 and 8p21.2, and minimal overlapping regions of gain, indicative of the presence of oncogenes, were found at 9q34.4-qter, 17q25-qter and 20q13.3-qter. There was a signi®cant association between Gleason score and losses and gains (P=0.003), and an association between chromosomal imbalance and high histological grade (P=0.008). Conclusion These results suggest that losses or gains of DNA in these regions are important for prostate cancer progression, and document the spectrum of chromosomal alterations in stage pT2N0 of clinically organ-con®ned prostate cancer.

Objective To determine the risk of post-operative group of non-irradiated patients, and no patients died. The mean follow-up was 22 months (range 10-37) complications in patients receiving high-dose pelvic irradiation before radical cystectomy and urinary and revealed satisfactory results in seven of 11 patients. A neovesicoperitoneal fistula developed in diversion. Patients and methods Of 300 patients who underwent one woman 10 months after surgery and was repaired by laparotomy. A neovesicovaginal fistula led to sup-orthotopic bladder replacement at our institution from 1986 to 1994, 11 patients (mean age 63 years, range ravesical urinary diversion in the second woman. Conclusions High-dose pelvic irradiation should not be 53-74) did so after receiving high-dose pelvic irradiation. The indication for cystectomy and urinary a primary contra-indication for orthotopic urinary diversion using segments of small intestine. For reconstruction was bladder cancer in seven men, prostate cancer in two men and a contracted bladder patients who undergo combined external and afterloading radiotherapy, the indication for orthotopic due to combined external pelvic irradiation and afterloading radiotherapy in two women.bladder replacement should be considered critically. Keywords Pelvic irradiation, ileal neobladder, compli-Results The post-operative course, including the duration of hospital stay, peri-operative complications and cations, results early functional results, did not differ from a control rates of anastomotic leakage, upper urinary tract