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Mesut Remzi

Publications and source records attributed to Mesut Remzi.

28 records · Page 2Linked to original sources
PubMed2003

Comparison of open versus laparoscopic pyeloplasty techniques in treatment of uretero-pelvic junction obstruction.

PURPOSE: Open dismembering pyeloplasty has high success rates but is associated with significant morbidity and moderate cosmetic results. Aim of this study was to evaluate laparoscopic dismembering pyeloplasty compared with other laparoscopic techniques and open surgery in this respect. MATERIAL AND METHODS: Between September 1999 and September 2002 we performed 25 laparoscopic dismembering (LDP), 15 laparoscopic non-dismembering (LNDP) and 15 open pyeloplasties (ODP) in 55 patients. For laparoscopy two 12 mm and two 5mm ports were used, a ureteric stent remained in place for 4 weeks. ODP was performed via a flank incision, a percutaneous ureteric stent and a nephrostomy remained for 10 days. Postoperative morbidity was assessed by visual analogue scale (VAS). Mean follow-up was 23.4+/-9.1 months (range 7-42) for laparoscopy vs. 21.9+/-8.8 (range 9-41) months for open surgery. Success was evaluated with postoperative i.v. pyelogram or diuretic nephrography. RESULTS: A crossing vessel could be identified in 82.5% (33/40) with laparoscopy vs. 47.0% (7/15) in ODP. Postoperative VAS score was lower in the laparoscopic group (day 1 3.5+/-1.6 vs. 5.4+/-3.1, day 5 0.9+/-1.2 vs. 3.1+/-1.8, p=0.001). Length of skin incision was 4.1+/-0.7 vs. 23.8+/-9.1 cm and hospital stay was 5.9+/-2.1 vs. 13.4+/-3.8 days for laparoscopy and ODP respectively. Success rate was 96.0% (24/25) for LDP, 73.3% (11/15) for LNDP and 93.4% (14/15) for ODP. Two patients with LNDP and one with ODP required re-operation. Clot retention was observed in two with LDP and one with ODP. Two abdominal wall herniations and one thromboembolism occurred with ODP. CONCLUSION: Short-term results demonstrate that dismembering laparoscopic pyeloplasty has the same success rates as open surgery but morbidity and complications are significantly decreased. Non-dismembering techniques have the least favourable results. This finding may suggest that LDP has the potential to replace open surgery as the gold standard for treatment of uretero-pelvic junction obstruction.

Adult↗
PubMed2003

An artificial neural network for prostate cancer staging when serum prostate specific antigen is 10 ng./ml. or less.

PURPOSE: An artificial neural network was developed to improve the prediction of pathological stage before radical prostatectomy based on variables available at biopsy and clinical parameters. MATERIALS AND METHODS: We used the prospectively accrued European prostate cancer detection data base to train an artificial neural network to predict pathological stage in 200 men with serum prostate specific antigen (PSA) 10 ng./ml. or less who underwent radical prostatectomy. Variables included in the artificial neural network were patient age, serum PSA, free-to-total PSA ratio, PSA velocity, transrectal ultrasound calculated total and transition zone volumes with their associated PSA parameters (transition zone PSA density and PSA density), digital rectal examination and Gleason score on biopsy. Two multilayer perceptron neural networks were trained on the remaining variables. Data on the 200 patients were divided randomly into a training set, a test set and a validation or prospective set. RESULTS: Overall classification accuracy of the artificial neural network was 92.7% and 84.2% for organ confined and advanced prostate cancer staging, respectively. For preoperatively predicting local versus advanced stage the area under the ROC curve for the artificial neural network was significantly larger (0.91) compared with logistic regression analysis (0.83), Gleason score (0.69), PSA density (0.68), prostate transition zone volume (0.63) and serum PSA (0.62) (all p <0.01). CONCLUSIONS: The artificial neural network outperformed logistic regression analysis and correctly predicted pathological stage in more than 90% of the validation patients with serum PSA 10 ng./ml. or less based on clinical, biochemical and biopsy data. In the future artificial neural networks may represent a significant step for improved staging of prostate cancer when counseling patients referred for radical prostatectomy or other curative treatments.

Adult↗
PubMed2003

Artificial neural networks for decision-making in urologic oncology.

Artificial neural networks (ANNs) are computational methodologies that perform multifactorial analyses, inspired by networks of biological neurons. Like neural networks, ANNs contain layers of simple points (nodes) of data that interract through carefully weighted connection lines. ANNs are "trained" and balanced by having been previously fed data, which the ANN uses as the means for adjusting its interconnections. Studies have shown that novel and highly accurate ANNs significantly enhance the ability to detect prostate cancer early (high sensitivity) while avoiding a greater number of unnecessary tissue samplings (high specificity). The use of ANNs in prostate cancer is ideal because of 1) multiple predicting factors that influence outcome; 2) the desire to offer individual consulting based on various tests; 3) the fact that prior logistic regression analysis results have had serious limitations in application; and 4) the need for an up-to-date tool that can apply easily to everyone. An ANN should be seen as an important tool that is complementary to the physician's personal knowledge and judgment in making decisions.

Journal Article↗
PubMed2002

Novel artificial neural network for early detection of prostate cancer.

PURPOSE: Two artificial neural networks (ANN) for the early detection of prostate cancer in men with total prostate-specific antigen (PSA) levels from 2.5 to 4 ng/mL and from 4 to 10 ng/mL were prospectively developed. The predictive accuracy of the ANN was compared with that obtained by use of conventional statistical analysis of standard PSA parameters. PATIENTS AND METHODS: Consecutive men with a serum total PSA level between 4 and 10 ng/mL (n = 974) and between 2.5 and 4 ng/mL (n = 272) were analyzed. A separate ANN model was developed for each group of patients. Analyses were performed to determine the presence of prostate cancer. RESULTS: The area under the receiver operator characteristic (ROC) curve (AUC) was 87.6% and 91.3% for the 2.5 to 4 ng/mL and 4 to 10 ng/mL ANN models, respectively. For the latter model, the AUC generated by the ANN was significantly higher than that produced by the single variables of total PSA, percentage of free PSA, PSA density of the transition zone (TZ), and TZ volume (P <.01), but not significantly higher compared with multivariate analysis. For the 2.5 to 4 ng/mL model, the AUC of the ANN ROC curve was significantly higher than the AUCs for percentage of free PSA (P =.0239), PSA-TZ (P =.0204), and PSA density and total prostate volume (P <.01 for both). CONCLUSION: The predictive accuracy of the ANN was superior to that of conventional PSA parameters. ANN models might change the way patients referred for early prostate cancer detection are counseled regarding the need for prostate biopsy.

Adult↗
PubMed2002

Complexed prostate-specific antigen, complexed prostate-specific antigen density of total and transition zone, complexed/total prostate-specific antigen ratio, free-to-total prostate-specific antigen ratio, density of total and transition zone prostate-specific antigen: results of the prospective multicenter European trial.

This prospective, multicenter European Prostate Cancer Detection study evaluated the value and performance of the molecular forms of prostate-specific antigen (PSA) and their derivatives in combination with prostate gland and transition zone volumes in early detection of prostate cancer in patients with PSA levels between 4 and 10 ng/mL. Of 750 men enrolled at 7 different European urology centers into the study between November 2001 and March 2002, 340 (45.3%) had a total PSA (tPSA) between 4 and 10 ng/mL (age range, 46 to 87 years). In all patients, the ratio of complexed PSA (cPSA) to tPSA (c/tPSA), cPSA density (cPSAD), cPSAD of the transition zone, PSA, free PSA (fPSA), ratio of fPSA to tPSA (f/tPSA), tPSA density (PSAD), and PSAD of the transition zone were measured and collected 5 to 10 minutes before the sextant biopsy with 2 additional transition zone cores. Measurements of tPSA and fPSA were done with the AxSYM test, whereas cPSA was measured with the ACS 180 cPSA assay. All patients had a transrectal ultrasound-guided sextant prostate biopsy, and 2 additional transition zone biopsies and total and transition zone volumes were measured at the time of biopsy. Histopathologic findings revealed benign histology in 237 patients and prostate cancer in 103 patients (69.7% and 30.3%, respectively). Statistically significant differences included larger total volumes, larger transition zone volumes, and f/tPSA in patients with benign disease (P = 0.0009, P <0.0001, P <0.0001, respectively). At 90% and 95% sensitivity, specificity of cPSA was significantly greater than that for PSA (P <0.0001). At sensitivity levels of 90% and 95%, the specificity of the cPSA assay using cutoff values of 3.06 and 2.52 ng/mL was 20.3% and 9.1%, respectively. A cPSA cutoff value of 6.95 ng/mL and 7.57 ng/mL afforded 90% and 95% specificity for detecting prostate cancer. The area under the curve (AUC) in the receiver operating characteristics curve of cPSA was statistically significantly higher compared with tPSA (60.8 vs 56.9, P = 0.032). AUC for volume-related parameters PSAD, cPSAD, PSAD of the transition zone, and cPSAD of the transition zone were 62.8%, 63.1%, 63.0%, and 63.6%, respectively. cPSA performs better than tPSA in the differentiation between benign disease and prostate cancer and provides similar information to the f/tPSA ratio. In addition, cPSA and cPSA volume-related parameters (cPSAD, cPSAD of the transition zone) further improved the specificity of PSA in early detection of prostate cancer.

Aged↗
PubMed2002

Efficacy of oral doxepin and piroxicam treatment for interstitial cystitis.

OBJECTIVE: To establish the efficacy of a multidrug oral treatment with the tricyclic antidepressant agent doxepin and the cyclooxygenase (COX) inhibitor piroxicam in patients with interstitial cystitis (IC), who had failed standard therapy in an open, prospective, nonrandomized study. METHODS: A total of 37 patients diagnosed with IC received 75 mg doxepin and 40 mg piroxicam daily. The treatment was termed DOXCAM. Effectiveness of therapy was assessed with frequency-volume charts, an IC symptom score and with cystometry prior to treatment, 8 weeks after the start and 4 weeks after termination of drug treatment. RESULTS: Medication was not tolerated by five patients. Twenty-six of 32 patients have experienced virtual total remission of symptoms (81%) and six patients had significant relief (19%). DOXCAM treatment resulted in a significant percent decrease in pain (65% versus 21%). Daytime frequency decreased from 17.6+/-5.7 to 11.3+/-3.6 voids while nocturia did not improve significantly. Twenty-three of the 26 patients who became symptom free and four of the six patients who showed significant improvement had a return of symptoms after cessation of therapy. CONCLUSION: It is reasonable to consider oral treatment with DOXCAM in those patients who have failed first-line therapies.

Administration, Oral↗
PubMed2002

Repeat prostate biopsy: who, how and when?. a review.

Urologists are frequently faced with the dilemma of treating a patient with a high index of suspicion of prostate cancer (PCa), but an initial set of negative biopsies. In this review, we evaluated the current knowledge on repeat prostate biopsies, focusing on when to perform them and in which patients, how many samples to take, where to direct the biopsies and what morbidity should be expected. We focussed on the available literature and the multicenter European Prostate Cancer Detection (EPCD) study. The EPCD study included 1051 men with a total PSA from 4 to 10 ng/ml who underwent a transrectal ultrasound (TRUS) guided sextant biopsy and a repeat biopsy in case of a negative initial biopsy. Most studies support that increasing the number of biopsy cores as compared to the sextant technique and improving prostate peripheral zone (PZ) sampling result in a significant improvement in the detection of prostate cancer without increase in morbidity or effects on quality of life. Re-biopsy can be performed 6 weeks later with no significant difference in pain or morbidity. At least 10% of patients with negative sextant prostatic biopsy results in the EPCD study were diagnosed with PCa on repeat biopsy, percent free PSA and PSA density of the transition zone being the most accurate predictors. Despite differences in location (more apico-dorsal) and multifocality, pathological and biochemical features of cancers detected on initial and repeat biopsy were similar, suggesting similar biological behavior and thus advocating for a repeat prostate biopsy in case of a negative finding on initial biopsy. Indications and ideal number of biopsy cores to take when repeating biopsies in patients who already underwent extensive biopsy protocols on the first biopsy remains to be determined.

Biopsy↗
PubMed2002

The pathophysiology of benign prostatic hyperplasia.

The development of human benign prostatic hyperplasia and its related signs and symptoms clearly requires a combination of testicular androgens and aging. Although the role of androgens as a causative factor for human benign prostatic hyperplasia is debated, they undoubtedly play at least a permissive role. The principle prostatic androgen is dihydrotestosterone. Two isoenzymes of 5-alpha reductase have been discovered. Type 2 is dominant in the genital issue. Testosterone is reduced by the 5-a reductase to dihydrotestosterone. Benign prostatic hyperplasia is predominantly due to stromal hyperplasia of the gland and affects more than 70% of men of 70 years or older with or without obstruction. Recent studies identified transforming growth factor-b, fibroblast growth factor and insulin-like growth factor family members as key regulators of cell proliferation and extracellular matrix turnover with interrelated activities. Furthermore, estrogens, andenergic signaling and inflammatory processes have been shown to have an impact. Without a solid understanding of the physiology and pathophysiology of benign prostatic hyperplasia it can be difficult to interpret the results of clinical trials and symptoms.

Aging↗
PubMed2002

Laparoscopic prostatectomy: where do we stand?

Laparoscopic radical prostatectomy is an effective treatment for localized prostate cancer. This cost-intensive and technically demanding operation currently takes longer than the standard open procedures, but with increasing experience, it is eventually associated with lower costs and is nearly as fast. As more urologists gain such experience, the laparoscopic approach may challenge the standard approaches.

Journal Article↗