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- Björk, Thomas, et al.
(författare)
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Comparison of analysis of the different prostate-specific antigen forms in serum for detection of clinically localized prostate cancer
- 1996
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Ingår i: Urology. - 1527-9995. ; 48:6, s. 882-888
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: To compare different forms and ratios of serum prostate-specific antigen (PSA) to determine which form or ratio provides optimal diagnostic specificity and sensitivity in distinguishing between benign prostatic hyperplasia (BPH) and clinically localized prostate cancer. METHODS: Serum samples were obtained from 47 patients with BPH and 39 with clinically localized prostate cancer. Patients with BPH underwent either transurethral resection of the prostate or transurethral microwave thermotherapy. Patients with prostate cancer, all of whom had no metastases on radionucleotide bone scans and no pelvic lymph node involvement, underwent either radical external beam radiation therapy or radical retropubic prostatectomy. All patients had pretreatment serum PSA levels between 1 and 20 ng/mL. The different forms of serum PSA (free PSA [PSA-F], PSA complexed to alpha 1-antichymotrypsin [PSA-ACT], and total PSA [PSA-T]) were measured using different monoclonal antibodies against PSA and ACT and immunofluorometric assay techniques. Furthermore, three ratios (PSA-F/PSA-T, PSA-ACT/PSA-T, and PSA-F/PSA-ACT) were calculated. RESULTS: By receiver operating characteristic curve analysis, the performance of the different forms and ratios were compared. The PSA-F/PSA-T ratio had the greatest area under the curve (AUC, 0.776), significantly larger than that for PSA-T (0.612; P = 0.024). For PSA-ACT/PSA-T, the AUC was 0.695 (P = 0.283 versus PSA-T) and 0.773 for PSA-F/PSA-ACT (P = 0.051 versus PSA-T). At a cutoff level < 0.17, PSA-F/PSA-T had a sensitivity of 79%, a specificity of 66%, and a positive predictive value of 66% compared with 74%, 38%, and 50%, respectively, for PSA-T at a cutoff level > 4.0 ng/mL. CONCLUSIONS: The PSA-F/PSA-T ratio gives the best diagnostic performance compared with that for other forms and ratios of PSA and will reduce the number of prostatic biopsies in patients with BPH.
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| 2. |
- Björk, Thomas, et al.
(författare)
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Rapid exponential elimination of free prostate-specific antigen contrasts the slow, capacity-limited elimination of PSA complexed to alpha 1-antichymotrypsin from serum
- 1998
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Ingår i: Urology. - 1527-9995. ; 51:1, s. 57-62
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: To study the rates of elimination of total prostate-specific antigen (PSA-T), free PSA (PSA-F), and PSA complexed to alpha 1-antichymotrypsin (PSA-ACT) from blood after radical retropubic prostatectomy (RRP). METHODS: We obtained venous blood from 10 patients with prostate cancer who were undergoing RRP. We analyzed PSA-F and PSA-ACT and equimolar detection of both of these forms together (PSA-T) by using immunofluorometric assays. An attempt was made to fit the serum concentrations of PSA-F, PSA-ACT, and PSA-T for each patient to exponential curves by applying one- and two-compartment models for pharmacokinetic analysis. RESULTS: Manipulation of the prostate during RRP resulted in a 3- to 28-fold increase in PSA-F concentrations in serum. Removal of the prostate resulted in a rapid, biexponential elimination of PSA-F from serum, corresponding to a mean initial (alpha) half-life of 0.81 hours and a mean terminal (beta) half-life of 13.9 hours. Serum PSA-ACT concentrations decreased by 20% to 40% immediately after removal of the gland; the elimination after surgery was slow and nonexponential, corresponding to a mean rate of 0.8 ng/mL/day. The elimination of PSA-T reflects a combination of the elimination patterns for PSA-F and PSA-ACT. CONCLUSIONS: The main proportion of PSA-F is rapidly eliminated from serum, possibly by glomerular filtration. PSA-F released during surgery did not form complexes with ACT, as suggested by the lack of PSA-ACT elevation in serum. The size (approximately 90 kDa) and the extensive in vitro stability of the PSA-ACT complex prevents renal clearance. The nonexponential elimination of the PSA-ACT complex is evidence of a capacity-limited process (e.g., metabolic transformation).
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| 3. |
- Bratt, Ola, et al.
(författare)
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Metaphase cytogenetics and DNA flow cytometry with analysis of S-phase fraction in prostate cancer: influence on prognosis
- 1996
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Ingår i: Urology. - 1527-9995. ; 47:2, s. 218-224
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: To compare the prognostic significance of chromosome aberrations, DNA ploidy, and S-phase fraction (SPF) in prostate adenocarcinomas and to compare the sensitivity of metaphase cytogenetics with flow cytometry (FCM) in detecting abnormal tumor clones. METHODS: Prostate adenocarcinomas from 57 men were previously successfully analyzed with metaphase cytogenetics. Archival material from these tumors were further analyzed with FCM for DNA content and SPF. RESULTS: The patients were followed for 4.5 to 7.7 years. DNA ploidy was analyzed in 51, and SPF in 45 of the 57 tumors. Clonal chromosomal aberrations, DNA aneuploidy, and high SPF were all significantly associated with poor survival. Of these three variables, SPF was the best predictor of survival, but compared with tumor stage and grade in multivariate analysis, SPF was not an independent prognostic factor. Patients with locally advanced tumors or metastatic disease with SPF less than 8% had a median survival of 5.9 years, compared with only 1.3 years for those with SPF more than 8%. Twenty-eight abnormal clones were detected with FCM and 20 with cytogenetic analysis, but only for two of these clones could the results from the two different methods be regarded as concordant. CONCLUSIONS: SPF was superior to karyotype and ploidy in predicting death in prostate cancer, but it remains to be shown whether SPF analysis adds prognostic information to tumor stage and grade. The cytogenetic analyses correlated poorly with results of FCM, indicating low sensitivity of both methods.
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| 4. |
- Davidsson, Thomas, et al.
(författare)
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Long-term metabolic effects of urinary diversion on skeletal bone: histomorphometric and mineralogic analysis
- 1995
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Ingår i: Urology. - 1527-9995. ; 46:3, s. 328-333
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES. To evaluate the long-term influence of different types of intestinal urinary diversion on skeletal bone and its mineral content. METHODS. Densitometry was used to estimate bone mineral content, and bone biopsies were analyzed with histomorphometric technique. The study comprised 20 patients with conduit urinary diversion and 19 with cecal continent reservoir, all followed up for more than 5 years, with normal or near-normal renal function. RESULTS. Bone mineral content did not differ significantly between the patients with cecal continent urinary reservoir and those with conduit diversion or between these groups and a reference group. At the cellular level, the histomorphometric analysis revealed no defective bone mineralization or increased bone resorption in either group of patients. The trabecular bone volume was greater than normal in the reservoir group, but not in the conduit group. The appositional rate was significantly below normal in both groups of patients, but did not differ between conduit and reservoir patients. CONCLUSIONS. Subtle changes in electrolytes and acid-base homeostasis identified in adults with intestinal segments incorporated in the urinary tract and with largely normal renal function do not seem to influence bone mineralization in the long term. At the cellular level, a lower than normal appositional rate was found in the patients with conduit or continent urinary diversion. In the latter group, this finding, together with increased trabecular bone volume, may indicate a decrease of bone turnover.
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