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Bob Djavan

Publications and source records attributed to Bob Djavan.

49 records · Page 3Linked to original sources
PubMed2003

A prospective randomized study of combined visual laser ablation and transurethral resection of the prostate versus transurethral prostatectomy alone.

INTRODUCTION: Visual laser ablation of the prostate (VLAP) has a clinical failure rate of up to 18% which is 3 times higher than transurethral resection of the prostate (TURP) alone. Prolonged spontaneous passage of necrotic debris is the major shortcoming of this method. Therefore combined visual laser-assisted and transurethral prostatectomy was compared to TURP alone. MATERIALS AND METHODS: 105 patients were evaluated in a prospective randomized study comparing TURP alone and VLAP combined with TURP. The patients were evaluated 1, 3 and 12 months after surgery. First VLAP was performed using a neodymium:yttrium-aluminum-garnet laser with the prolase fiber followed by standard resection of the necrotic and remaining prostatic tissue. Treatment efficacy was assessed by the American Urological Association (AUA) symptom score, measurements of peak urinary flow, residual urine volume, intraoperative bleeding, and by the occurrence of intra- and postoperative complications. RESULTS: The use of VLAP and consecutive TURP improved the AUA symptom score, urinary flow and residual volume and was comparable in all patients treated. Intraoperative bleeding was significantly reduced from 522 +/- 45 ml by TURP to 214 +/- 33 ml by VLAP+TURP (p < 0.05). There was a significant improvement in the postoperative values of the parameters observed in both groups. CONCLUSIONS: It appears that the combined method for treatment of benign prostatic hyperplasia reduced the specific intraoperative morbidity of TURP while achieving the same clinical effect as TURP alone.

Aged↗
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

Minimally invasive therapies for benign prostatic hyperplasia in the new millennium: long-term data.

Over the last decade, a number of minimally invasive therapies have been investigated for the treatment of symptomatic benign prostatic hyperplasia. Most of these therapies use thermal energy to ablate prostatic tissue. The major common problem with all these new minimally invasive therapies has been the lack of long-term data concerning efficacy, re-intervention rates and side-effects. We present here the available long-term data on these alternative minimally invasive therapies for benign prostatic hyperplasia and their current place in the urologist's armamentarium.

Catheter Ablation↗
PubMed2002

Morphological and biological predictors for treatment outcome of transurethral microwave thermotherapy.

The proliferation of prostatic tissue as a result of ageing typically leads to prostatic enlargement, which often causes obstruction of urine outflow from the bladder, clinically lower urinary tract symptoms, detrusor instability, incomplete bladder emptying, urinary infection, and finally acute urinary retention. The first approach to therapy depending on the severity of the symptoms is usually medical management (phytotherapy, alpha-blockers, 5 alpha-reductase inhibitors) before surgical procedures are performed. The reference standard for treatment of benign prostatic hyperplasia is transurethral resection of the prostate, although the introduction of minimally invasive alternatives such as transurethral microwave thermotherapy has led to a new era in surgical management. Suitable patients must be selected carefully on the basis of individual parameters that predict a favourable result.

Humans↗
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↗
PubMed2002

The picture of the prostatic lymphokine network is becoming increasingly complex.

The immunology of the prostate has recently developed into a new field of research in urology. Although we do not yet understand why the leukocyte population increases, we know that most resected prostate tissue shows signs of an inflammatory reaction. Different types of inflammation exist, and must be distinguished carefully according to distribution and location of leukocytes and histology of the surrounding tissue. This article reviews recent findings and discusses the complex mechanisms involved in the prostatic inflammatory response. The roles of estrogen, interleukin (IL)-6, IL-8, IL-15, and IL-17 are examined.

Journal Article↗