Search PubMed⌕ Search

Biomedical subjects

B Djavan

Publications and source records attributed to B Djavan.

66 records · Page 4Linked to original sources
PubMed1998

Prostate specific antigen density of the transition zone for early detection of prostate cancer.

PURPOSE: We compare the ability of several prostate specific antigen (PSA) parameters, including PSA density of the whole prostate and of the transition zone, percent free PSA and PSA velocity, to enhance the specificity for prostate cancer detection and to reduce unnecessary biopsies in men with serum PSA levels of 4 to 10.0 ng./ml. MATERIALS AND METHODS: This prospective study included 559 consecutive men referred for early prostate detection or lower urinary tract symptoms who had a serum PSA of 4.0 to 10.0 ng./ml. All men underwent prostatic ultrasonography and sextant biopsy with 2 additional transition zone biopsies. Specific biopsies of abnormal findings on digital rectal examination were also performed. In all cases if first biopsies were negative an additional set of biopsies was performed within 6 weeks. The ability of PSA density, PSA transition zone, PSA velocity and percent free PSA to improve the power of PSA in the detection of prostate cancer was evaluated with univariate and multivariate analyses as well as receiver operating characteristics (ROC) curves. RESULTS: Of 559 patients 342 had histologically confirmed benign prostatic hyperplasia and 217 had prostate cancer. Mean serum PSA, PSA velocity, PSA density and PSA transition zone were statistically higher (p <0.018, p <0.037, p <0.0001 and p <0.0001, respectively) and percent free PSA was statistically lower (p <0.0001) in patients with prostate cancer than in those with benign disease. Multivariate analysis and ROC curves showed that PSA transition zone and percent free PSA were the most powerful and highly significant predictors of prostate cancer. Areas under the ROC curve for PSA transition zone and percent free PSA were 0.827 and 0.778, respectively (p=0.01 McNemar test). Combination of free-to-total PSA with PSA transition zone significantly increased the area under the ROC curve compared to PSA transition zone alone (p=0.020). With a 95% sensitivity for prostate cancer detection a PSA transition zone cutoff of 0.25 ng./ml./cc would result in the lowest number of unnecessary biopsies (47% PSA transition zone specificity) compared to all other PSA parameters. However, total prostate volume (greater than 30 cc in 422 men or less than 30 cc in 137) was an important factor in predicting the statistical performance of PSA transition zone. In fact, PSA transition zone did not outperform free percent PSA in sensitivity and specificity when the entire prostate gland volume was less than 30 cc (p=0.094 McNemar test). CONCLUSIONS: PSA density of the transition zone enhances the specificity of serum PSA for prostate cancer detection in referred patients with a serum PSA of 4.0 to 10.0 ng./ml. compared to other PSA parameters currently available. While PSA transition zone was more effective in prostates greater than 30 cc and percent free PSA was more effective in prostates less than 30 cc, the combination of percent free PSA with PSA transition zone further increased prostate cancer prediction.

Aged↗
PubMed1998

Decreased elastin gene expression in noncompliant human bladder tissue: a competitive reverse transcriptase-polymerase chain reaction analysis.

PURPOSE: In low capacity noncompliant fibrotic bladders, as seen in patients with myelomeningocele, elevated storage pressures ultimately can lead to renal damage. Earlier studies have described an increased deposition of extracellular matrix protein, especially type III collagen, in the detrusor muscle. We analyzed elastin gene expression and quantified elastin gene alteration in the obstructed bladder, correlating urodynamically measured compliance with elastin messenger ribonucleic acid (mRNA) concentration. MATERIALS AND METHODS: Using a reverse transcriptase-polymerase chain reaction quantitative technique elastin mRNA can be reliably measured in 5 to 8 mg. samples of bladder tissue. We compared tissue samples from patients with urodynamically demonstrated noncompliant bladders (less than 10 cc/cm. water) to a control group with normal bladder compliance (greater than 20 cc/cm. water). Tissue samples were homogenized and sonicated, and complementary deoxyribonucleic acid (cDNA) was synthetized from mRNA using reverse transcriptase. Wild type and mutant elastin cDNA were synthetized, and target elastin cDNA with unknown concentration was competitively co-amplified with known serial dilutions of the mutant template (competitive polymerase chain reaction). Computerized densitometry allowing cDNA concentration measurement was performed and competitive reverse transcriptase-polymerase chain reaction was repeated at least twice for every sample. RESULTS: Elastin mRNA concentration ranged from 27.6 to 63.2 attomole per mg. in noncompliant bladders compared to 62 to 190 attomole per mg. in controls. The variation within the same sample was less than 10%. There was a statistically significant difference between mean plus or minus standard deviation elastin cDNA concentration in noncompliant bladders (37.48 attomole per mg. +/- 12.06) and controls (119.63+/-41.01 attomole per mg.). CONCLUSIONS: A significant decrease in elastin mRNA matches the decreased deposition of elastic fibers noted in previous immunohistochemical studies. Our data suggest that this decrease is mainly due to a transcriptional down regulation of the elastin gene in noncompliant bladders.

Adolescent↗
PubMed1997

Urodynamic assessment of patients with acute urinary retention: is treatment failure after prostatectomy predictable?

PURPOSE: Some patients with acute urinary retention due to benign prostatic hyperplasia do not have successful outcome after prostatectomy and require either a chronic indwelling urethral catheter or clean intermittent catheterization. Urodynamic and clinical parameters were examined preoperatively in 81 men 56 to 93 years old (mean age 72 years) in search of an outcome predictor after prostatectomy. MATERIALS AND METHODS: International Prostate Symptom Score, prostate volume, retention episodes, retention volume and urodynamic parameters from a multichannel pressure-flow study were analyzed preoperatively and postoperatively. All patients underwent transurethral prostatectomy and were reexamined 2, 4, 12 and 24 weeks after surgery. A multichannel pressure-flow study was performed preoperatively and 12 weeks postoperatively. RESULTS: At 24 weeks postoperatively 11 patients (13%) were unable to void and therefore classified as treatment failures while the remaining patients voided spontaneously and were classified as treatment successes. There were statistically significant differences (p < 0.005) between treatment failure and treatment success regarding age (83.5 +/- 7 versus 70.1 +/- 8 years), preoperative volume of retention (1,780 versus 1,080 ml.), and maximal detrusor pressure (24.4 versus 73.5 cm. water), but not to International Prostate Symptom Score, episodes of retention and prostate volume. The ability to void during preoperative pressure flow study and the presence of detrusor instability predicted good outcome. In treatment success patients postoperative urodynamic data showed significant decrease in detrusor pressure at maximum flow rate (from 80.8 +/- 33 to 34.6 +/- 10 cm. water). Those with treatment failure had an increase in maximal detrusor pressure (from 26 +/- 12 to 42.6 +/- 13 cm. water), suggesting detrusor recovery. CONCLUSIONS: Patients with acute urinary retention, age 80 years or older, with retention volume greater than 1,500 ml., no evidence of instability and maximal detrusor pressure less than 28 cm. water are at high risk of treatment failure. However, despite treatment failure the detrusor may recover in patients younger than 80. Therefore, prostatectomy should still be performed in this group (less than 80 years old) even if preoperative urodynamics suggest an unfavorable outcome.

Acute Disease↗
PubMed1997

Transperineal radiofrequency interstitial tumor ablation of the prostate: correlation of magnetic resonance imaging with histopathologic examination.

OBJECTIVES: Radiofrequency (RF) energy has recently been employed to destroy human tissue in vivo. The purpose of this study was to investigate the safety of this approach in localized carcinoma of the prostate (CaP) and specifically, the predictability of lesions obtained with radiofrequency interstitial tumor ablation (RITA). METHODS: Using RITA, a total of 21 lesions were induced in 10 patients with localized CaP (mean age 70.4 years). RF was delivered transperineally under transrectal ultrasound (TRUS) guidance. All patients underwent endorectal magnetic resonance imaging (MRI) before and after treatment. Radical prostatectomy was performed in all patients 1 to 7 days after RITA. Three of the patients were treated with local anesthesia only. The predictability of the thermal lesion was assessed by correlating the findings of intraoperative TRUS, pre- and post-RITA endorectal MRI, and the histologic examination of the specimen. RESULTS: Postoperatively, patients were catheterized for an average of 1.8 days (1 to 3 days). Lesions of 2 x 2 x 2 cm were targeted. Average lesion diameters obtained on MRI were 2.08 +/- 0.23 x 2.09 +/- 0.36 x 2.28 +/- 0.21 cm. Average lesion diameters defined by coagulative necrosis at histologic examination were 2.20 +/- 0.23 x 2.10 +/- 0.31 x 2.38 +/- 0.14 cm. There were no statistically significant differences (P = 0.377) between average lesion volume on MRI (5.37 +/- 1.83 cm3) and average lesion volume at histology (5.86 +/- 1.63 cm3). No complications or adverse events were noted. CONCLUSIONS: In this Phase I study, RITA was shown to be safe and feasible, and to result in lesions that were predictable in size and location. MRI accurately visualized and verified the area of coagulative necrosis as documented at histology. The procedure is technically simple and can even be performed under local anesthesia.

Aged↗
PubMed1997

Is obstruction predictable by clinical evaluation in patients with lower urinary tract symptoms?

OBJECTIVE: To determine whether it is possible to predict the presence of bladder outlet obstruction (BOO) by non-invasive clinical variables in patients with lower urinary tract symptoms (LUTS) suggestive of BOO. PATIENTS AND METHODS: Patients with LUTS suggestive of BOO were entered into a prospective protocol evaluating the International Prostate Symptom Score (IPSS), prostate size, non-invasive uroflow, post-void residual urine volume (PVR) and a pressure flow study. Only patients with a maximum flow rate (Qmax) of < or = 15 mL/s and an IPSS > or = 7 were included. The study comprised 253 patients; the degree of obstruction was correlated to several non-invasive clinical variables. Subsequently nomograms were developed by multiple logistic regression analysis to obtain the probability of BOO in patients with LUTS. RESULTS: Prostate volume, Qmax, PVR and voided volume correlated significantly with the degree of BOO rated according to the linear passive urethral resistance relation (linPURR). In contrast, there was no such correlation for the IPSS and the quality-of-life question of the IPSS. The percentage of patients with BOO defined by a linPURR of 3-6 decreased from 85% in those with a Qmax of 0-5 mL/s to 60% (Qmax 6-10 mL/s) and 44% (Qmax 11-15 mL/s). In parallel, the percentage of patients with BOO increased from 53% of those with a prostate volume of < or = 50 mL, to 79% of those with prostates of 51-100 mL and 75% of those > 100 mL. Based on Qmax, PVR and prostate volume, nomograms were established by multiple logistic regression analysis for the probability of BOO in patients with LUTS. CONCLUSION: The nomograms presented herein should help the clinician to identify patients with LUTS who should undergo pressure flow studies before surgical intervention to detect the presence of obstruction and in whom these studies can be safely spared.

Adolescent↗
PubMed1997

Prostate specific antigen density of the transition zone: a new effective parameter for prostate cancer prediction.

PURPOSE: Use of prostate specific antigen (PSA) density to enhance the predictive value of detecting prostate cancer at intermediate PSA levels has been limited due to contradictory results in large scale studies. Most PSA leakage from the benign prostate into the serum comes from the transition zone. Therefore, in patients with benign prostatic hyperplasia (BPH) and prostate cancer with a serum PSA of less than 10 ng/ml. we studied and compared the values of PSA density of the total prostate and the transition zone. We examined the ability of PSA density of the transition zone to enhance prostate cancer detection in patients with intermediate PSA levels. MATERIALS AND METHODS: The volumes of the entire prostate and of the transition zone were determined by transrectal ultrasound. PSA density for both regions was calculated in 88 patients with histologically confirmed prostate cancer (radical prostatectomy), and 74 with BPH and histologically proved benign disease. RESULTS: Average total prostate PSA density plus or minus standard deviation was 0.12 +/- 0.07 and 0.22 +/- 0.12 ng./ml./cc in patients with BPH and prostate cancer, respectively, while average PSA density of the transition zone was 0.21 +/- 0.13 and 1.02 +/- 0.70 ng./ml./cc, respectively (p < 0.0001). If a total prostate PSA density of 0.15 had been chosen, the cancer would have been missed in 34% of the patients compared to 10% if a cutoff value of 0.35 for PSA density of the transition zone had been chosen (p < 0.001). Overall, in patients with a PSA of 0.25 to 10.0 ng./ml. the sensitivity and specificity of PSA density of the transition zone for predicting prostate cancer at a 0.35 cutoff value were 90 and 93%, respectively, compared to 94 and 89%, respectively, for those with a PSA of 4 to 10 ng./ml. CONCLUSIONS: In our study PSA density of the transition zone was much more accurate in predicting prostate cancer than was total prostate PSA density for PSA levels of less than 10 ng./ml. With respect to the high sensitivity and specificity, if confirmed in large prospective studies, including patients seen for early diagnosis, PSA density of the transition zone could become a routine tool for urologists in the prediction of prostate cancer in men with a PSA of 4 to 10 ng./ml.

Aged↗
PubMed1996

[The effect of 5-alpha-reductase inhibitors on benign prostatic hyperplasia].

The prevalence of BPH is high in elderly men with more than 60% of patients over the age of 60 experiencing some form of prostatism. Balancing the superior benefit of TUR/P are the small but significant risks and complications of surgery and the high cost of the procedure. The WHO guidelines recommend finasteride or alpha-blockers as treatment options for men with bothersome symptoms. Finasteride therapy reduces the volume of the hyperplastic prostate gland by more than 20%, improves the urinary flow rate and the symptoms associated with bladder outlet obstruction. Although statistically significant, results obtained with finasteride are just slightly better than placebo and TUR/P still offers the greatest improvement of symptoms. Finasteride is well tolerated and adverse events are rare. However, it decreases serum PSA (prostate specific antigen) by 50%, suggesting careful monitoring and exclusion of prostate cancer before initiation and during therapy. Current research is focusing on developing new 5-alpha-reductase inhibitors (type I and II) using polyunsaturated fatty acids and nonsteroidal inhibitors. Given the multifactorial nature of BPH, further clinical trials combining 5-alpha-reductors inhibitors and 5-alpha-receptor blockers are still needed.

5-alpha Reductase Inhibitors↗
PubMed1995

Radical retropubic prostatectomy for localized carcinoma of the prostate in a large metropolitan hospital: changing trends over a 10-year period (1984-1994). Dallas Outcomes Research Group for Urological Disorders.

OBJECTIVES: To analyze changing trends in the surgical treatment for localized carcinoma of the prostate in a large metropolitan community hospital over a 10-year period from 1984 to 1994. METHODS: The records of all 428 patients who underwent radical prostatectomy for localized carcinoma of the prostate from January 1, 1984, to January 1, 1994, at a large metropolitan community hospital (Baylor University Medical Center, Dallas, Tex) were retrieved and data abstracted in a predefined computerized database by a urology resident who was not part of the patient's surgical team. The abstracted data included attending surgeon, date of surgery, patient's age, clinical stage at presentation and pathologic stage, prostate-specific antigen (PSA), perioperative events, such as duration of surgery, blood loss, transfusion, duration of hospital stay, comorbidities according to the Charlson comorbidity index, and others. The data were analyzed in regard to changes over the 10-year period and stratified by a variety of parameters. RESULTS: The number of radical prostatectomies performed increased by fourfold from 1984 to 1993. The distribution of clinical stage and the incidence of pathologic upstaging noted in the 428 cases were similar to other series reported in the literature. The average age of patients decreased from 67 to 63 years over the 10 years (average calculated in increments of 15 cases in ascending order). Similarly, over time the average duration of surgery, average blood loss, average use of transfusion, and the average duration of hospital stay decreased. When the cases were grouped by individual attending surgeon, whose numerical surgical experience during that time period ranged from 1 to 76 cases, no correlation was noted between the numerical experience and these outcomes. CONCLUSIONS: As opposed to the national Medicare experience recently reported by the Prostate Patients Outcome Research Team, the increase in the number of cases performed was mostly due to patients under the age of 70 years, considered reasonable candidates for radical prostatectomy. Independent of numerical experience of individual attending surgeons, duration of surgery, blood loss, transfusion rates, and duration of hospital stay decreased during this period. This might indicate a learning effect due to continuing education, exchange of ideas, published technical improvements in the surgical procedure, and other factors, ultimately benefiting the patient by improving outcomes.

Adult↗
PubMed1995

False-positive serum prostate-specific antigen values in a patient with non-Hodgkin lymphoma of the kidney.

Prostate-specific antigen (PSA) is the clinically most useful tumor marker for prostate cancer. Although false-positive elevations have been reported due to disease processes outside the prostate gland with the use of the polyclonal assay, such false-positive test results have been exceedingly rare with the use of the monoclonal assay. We report the case of a patient diagnosed with a B-cell lymphoma of the kidney and a significant elevation of serum PSA levels by monoclonal assay in the absence of either inflammatory or malignant prostate disease. PSA returned to normal during lymphoma-specific chemotherapy with a cyclophosphamide, mechlorethamine, vincristine, procarbazine, prednisone regimen. Possible explanations and clinical implications are discussed.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1995

Mucinous adenocarcinoma in defunctionalized bladders.

Primary adenocarcinoma of the bladder accounts for less than 2% of all bladder cancers. There is no report of such a case in a defunctionalized bladder. All reported cases of carcinoma in defunctionalized bladders were either squamous cell, signet ring cell, or transitional cell carcinoma, detected within an average of 5 years after urinary diversion, and all have been associated with chronic inflammation of the bladder. We report on 2 cases of adenocarcinoma that developed in defunctionalized bladders 30 and 8 years after ileal loop diversion for prune belly syndrome and neurogenic bladder, respectively.

Adenocarcinoma, Mucinous↗