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At least 433 records · Page 24Linked to original sources
PubMed2001

Prostate-specific antigen (PSA) value change after antibacterial therapy of prostate inflammation, as a diagnostic method for prostate cancer screening in cases of PSA value within 4-10 ng/ml and nonsuspicious results of digital rectal examination.

OBJECTIVES: Investigation of the possibilities of improving the accuracy of prostate cancer (PC) screening among patients with a PSA value of 4-10 ng/ml and nonsuspicious results of digital rectal examination (DRE), using as diagnostic method the PSA value change (PSA-VCh) after antibacterial treatment of prostate inflammation. METHODS: The study included 61 patients with PSA 4-10 ng/ml, nonsuspicious DRE and inflammation in expressed prostate secretion (EPS). All these patients underwent antibacterial therapy with the following repeated PSA determination and PSA-VCh assessment. RESULTS: Antibacterial therapy led to PSA decrease in 80% of cases. Effectiveness of PSA-VCh in PC screening was estimated. Sensitivity of PSA-VCh (with cut-off point -0.1.100%) equaled 85%, specificity 96%, positive predictive value 85% and negative predictive value 96%. CONCLUSIONS: Prostate inflammation proves to be a significant factor contributing to serum PSA elevation up to 10 ng/ml among patients with nonsuspicious DRE. Assessment of PSA-VCh after antibacterial treatment can improve PC screening accuracy in cases of PSA 4-10 ng/ml, nonsuspicious DRE and inflammation in EPS.

Aged↗
PubMed1992

Prediction of pelvic lymph node metastases by a prostate-specific antigen and prostatic acid phosphatase in clinical T3/T4M0 prostatic cancer.

Prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP) were determined in the serum of 69 patients with clinical T3/T4M0 prostatic cancer before staging lymphadenectomy. In principle, high-dose radiotherapy was given only to patients of pathological N0 category. Seventeen patients had a prelymphadenectomy PSA level below the normal upper reference limit (10 micrograms/l) and only 3 of them had pelvic lymph node metastases. Fifteen of 52 patients with a preoperative PSA level > or = 10 micrograms/l were of N0 category. Only 8 of the 41 evaluable patients had PAP values above the normal range, and 6 of these 8 patients had pelvic lymph node metastases. Preoperative PSA values, but not preoperative PAP levels, assist the clinician in predicting regional lymph node metastases in patients with clinical T3/T4M0 prostatic cancer. Two-thirds of the patients with T3/T4 tumours and PSA values between 10 and 50 micrograms/l have regional lymph node metastases. About 80% of the patients with PSA levels < 10 micrograms/l belong to the N0 category. About 75% of the patients with PSA > 50 micrograms/l have N+ disease. Taking into account the individual preoperative PSA values, the indication for preradiotherapy staging lymphadenectomy should be balanced between the chance of demonstrating N+ disease, the expected postoperative morbidity and the benefit for the patient found to be of N0 category.

Acid Phosphatase↗
PubMed1995

Prostate-specific antigen as a unique routine test in monitoring therapy for inoperable prostate cancer: comparison with radionuclide bone scan and prostatic acid phosphatase.

The aim of the present investigation was the evaluation of cost-effectiveness of variables used in monitoring patients with inoperable prostate cancer. Prostate-specific antigen (PSA), prostatic acid phosphatase (PAP), and radionuclide bone scan were considered. The tumor marker positivity was assessed according to dynamic criteria (> 50% increase between consecutive samples). 108 patients entered the study; 72 patients treated with a luteinizing hormone-releasing hormone analogue were followed up for periods ranging from 12 to 64 months. PSA and PAP levels were measured using immunometric assays. Both cutoff-based and dynamic, serial sample-based decision criteria were employed. With respect to a positive bone scan, PSA showed negative predictive values of 82 and 77%, respectively, using 4 and 10 ng/ml as cutoff points. Progression of the disease to the bone occurred in 20 patients: in 17 PSA was the first indicator of progression, in the other 3 PAP anticipated PSA for a very short time (3-4 months), which was not of relevance to clinical decisions. PAP is less specific and sensitive than PSA; PAP may eventually provide information on disease status in a limited percentage of patients with advanced prostate cancer treated with androgen ablation, being differently regulated with respect to PSA. No increasing PSA profile was detected in patients who responded to the therapy. From the results of the present investigation, we draw the following conclusions: (1) PSA can be used reliably as a unique tool in the follow-up of patients for the early detection of progressive disease, and (2) dynamic criteria of evaluation of serial PSA determinations probably provide more effective and earlier clinical information.

Acid Phosphatase↗
PubMed1997

Diagnosis of prostate cancer: optimal number of prostate biopsies related to serum prostate-specific antigen and findings on digital rectal examination.

The optimal number of core biopsies of the prostate that are needed for the detection of prostate cancer is unknown. A retrospective review of protocols and charts concerning 1149 transrectal ultrasound examinations with biopsy performed in 1013 patients was undertaken. Cancer detection rate was correlated to findings on digital rectal examination (DRE), serum levels of prostate-specific antigen (PSA) and number of biopsies taken. The cancer detection rate was significantly higher in patients who had five or more cores taken compared to those who had four or less (49% versus 35%, p < 0.05) in patients with serum PSA less than 10 ng/ml and a DRE suspicious of malignancy. The same trend was seen in patients with normal DRE and PSA less than 10 ng/ml (14% versus 8%, p = 0.057), while the detection rate for prostate cancer was unaffected by the number of cores taken if serum PSA was above 10 ng/ml.

Adult↗
PubMed2000

Ratio of free or complexed prostate-specific antigen (PSA) to total PSA: which ratio improves differentiation between benign prostatic hyperplasia and prostate cancer?

BACKGROUND: The aim of this study was to compare the diagnostic utility of a new assay that measures all forms of prostate-specific antigen complexed (cPSA) to serum proteins except alpha(2)-macroglobulin with the assay of free PSA (fPSA) and the corresponding ratios to total PSA (tPSA) to improve the differentiation between benign prostatic hyperplasia (BPH) and prostate cancer (PCa). METHODS: Serum samples were collected from 91 men without prostate disease and with normal digital rectal examination (controls), 144 untreated patients with PCa, and 89 patients with BPH. tPSA and cPSA were measured using the Bayer Immuno 1 system; fPSA and the additional tPSA were measured with the Roche Elecsys system. RESULTS: The median cPSA/tPSA, fPSA/tPSA, and fPSA/cPSA ratios were significantly different between patients with BPH and PCa (78.7% vs 90.7%, 25.5% vs 12.1%, and 36.8% vs 14.3%, respectively; P <0.001). No correlations of cPSA and its ratios to tumor stage and grade were found. ROC analysis showed that cPSA was not different from tPSA (areas under the curve, 0.632 vs 0.568), whereas the cPSA/tPSA ratio was similar to the fPSA/tPSA ratio in increasing discrimination between BPH and PCa patients with tPSA concentrations in the tPSA gray zone between 2 and 10 microg/L (areas under the curve, 0.851 vs 0.838). CONCLUSIONS: Compared with tPSA, the fPSA/tPSA and cPSA/tPSA ratios both improve the differentiation between BPH and PCa comparably and are similarly effective in reducing the rate of unnecessary biopsies, whereas cPSA alone does not have any effect.

Adult↗
PubMedDate not supplied

Serum-to-urinary prostate-specific antigen ratio in patients with benign prostatic hyperplasia and prostate cancer.

BACKGROUND: Prostate-specific antigen (PSA) is the single most important tumor marker in early detection and monitoring of prostate cancer (CaP). However, routine analysis of serum PSA concentrations does not allow differentiation between CaP and prostatic diseases. The aim of the present study was to evaluate the usefulness of the serum-to-urinary PSA ratio in a clinical setting. MATERIALS AND METHODS: In a retrospective clinical study, we determined serum and urine PSA concentrations in 48 patients with benign prostatic hyperplasia (BPH) and 57 patients with histologically confirmed CaP. RESULTS: The serum-to-urinary PSA ratio is able to discriminate BPH from CaP. CONCLUSIONS: Determination of the serum-to-urinary PSA ratio enhances the specificity of PSA in screening for CaP and monitoring of patients with CaP under androgen deprivation therapy.

Aged↗
PubMed2002

The proportion of prostate-specific antigen (PSA) complexed to alpha(1)-antichymotrypsin improves the discrimination between prostate cancer and benign prostatic hyperplasia in men with a total PSA of 10 to 30 microg/L.

BACKGROUND: The aim of this study was to assess the diagnostic accuracy of the proportion of prostate-specific antigen (PSA) complexed to alpha(1)-antichymotrypsin (PSA-alpha(1)ACT:PSA ratio) in the differential diagnosis of prostate cancer (CaP) and benign prostatic hyperplasia (BPH) in men with total PSA of 10-30 microg/L. METHODS: We used our immunoassays (ELISAs) for total PSA and PSA-alpha(1)ACT complex to study 146 men. In 123, total PSA was between 10 and 20 microg/L; 66 of these had CaP and 57 BPH. In 23 men, total PSA was between 20 and 30 microg/L; 14 of these had CaP and 9 BPH. We calculated the area under the ROC curves (AUC) for total PSA, PSA-alpha(1)ACT complex, and PSA-alpha(1)ACT:PSA ratio, and determined the cutoff points that gave sensitivities approaching 100%. RESULTS: In the total PSA range between 10 and 20 microg/L, the AUC was significantly higher for the PSA-alpha(1)ACT:PSA ratio (0.850) than for total PSA (0.507) and PSA-alpha(1)ACT complex (0.710; P <0.0001). A cutoff ratio of 0.62 would have permitted diagnosis of all 66 patients with CaP (100% sensitivity) and avoided 19% of unnecessary biopsies (11 of 57 patients). In the total PSA range between 20 and 30 microg/L, the AUC for the PSA-alpha(1)ACT:PSA ratio (0.980; 95% confidence interval, 0.82-0.99) was greater than the AUC for total PSA (0.750; 95% confidence interval, 0.51-0.89; P = 0.042). In this range, a cutoff point of 0.64 would have permitted the correct diagnosis of all 14 patients with CaP and 6 of the 9 with BPH. CONCLUSIONS: The diagnostic accuracy of the PSA-alpha(1)ACT:PSA ratio persists at high total PSA concentrations, increasing the specificity of total PSA. Prospective studies with large numbers of patients are needed to assess whether the ratio of PSA-alpha(1)ACT to total PSA is a useful tool to avoid unnecessary prostatic biopsy in patients with a total PSA >10 microg/L.

Aged↗
PubMed2002

Comparative analysis of prostatic acid phosphatase and prostate-specific antigen mRNA levels in hyperplastic prostate stimulated with steroid hormones and growth factors.

Prostatic acid phosphatase (PAP) and prostate-specific antigen (PSA) are the markers of human prostatic gland. However, it is still not completely understood if and how, steroid hormones and growth factors affect their expression and metabolism in the respect to the major pathologies of the gland. Appropriate studies were carried out on histopathologically diagnosed benign prostatic hyperplasia--BPH (n = 42) using tissue slices and cells derived from them. They were incubated with steroid hormones: 5-alpha-dihydrotestosterone (DHT), estradiol (E) and growth factors: epidermal growth factor (EGF), basic fibroblastic growth factor (bFGF) under culture conditions for up to 24 hours. P-labelled specific oligonucleotide probes were used to analyze total RNA isolated from each sample for the presence of PAP and PSA mRNAs. DHT, E, bFGF, EGF or both DHT + bFGF and DHT + EGF increased PAP and PSA mRNA levels in a time- and dose-dependent manner. The highest and statistically significant increase (P < 0.001) for PAP mRNA was observed when DHT + bFGF were present in the medium while for PSA mRNA if DHT + EGF were added to the medium. Slow but constant decrease of PAP and PSA mRNA levels was observed in the absence of each of these factors in the incubation medium. The results suggest that early expression of PSA and PAP genes and/or their mRNA stability strongly depend on DHT while differ in their response to EGF and bFGF.

Acid Phosphatase↗
PubMed1990

[Changes in prostatic acid phosphatase, gamma-seminoprotein and prostate specific antigen after endocrine therapy for stage D2 prostate cancer].

Prostatic acid phosphatase (PAP), gamma-seminoprotein (gamma-Sm) and prostate specific antigen (PSA) were examined on 120 cases of stage D2 prostate cancer between 1979 and 1989. All patients received endocrine therapy as the first treatment; castration and immediate administration of estrogen or antiandrogen (101), LH-RH analogs (13), estrogen (3) and antiandrogen (3). The actuarial survival rates were calculated by the cause-specific survival method. Pretreatment levels of PAP, gamma-Sm and PSA did not influence prognosis. After start of treatment, the relationship between the changes of the markers and prognosis were examined. At 1 month after the start of the treatment, normalization of PAP or gamma-Sm was not reflected in the following course. On the contrary, at 3 and 6 months, groups with normalization of PAP or gamma-Sm showed better prognosis than those with elevated levels. The same tendency of PSA was obtained at 6 months after start of treatment. In patients with normalized PAP at 3 months, abnormal gamma-Sm showed worse prognosis than normalized gamma-Sm. Therefore, the significance of determination on the two markers was manifested. As histological grade influenced the following course, poorly differentiated adenocarcinoma with normalized PAP at 3 months showed better prognosis than those with elevated levels. In conclusion, it is worthwhile to measure multiple markers for predicting the prognosis of stage D2 prostate cancer treated with endocrine therapy.

Acid Phosphatase↗
PubMed1993

Prostate-specific antigen and transrectal ultrasound of the prostate in detection of prostate cancer.

Detection of prostate cancer can be enhanced over the level historically obtained by digital rectal examination through the combined use of serum prostate-specific antigen and digital rectal examination, followed by transrectal ultrasonic examination of the prostate and ultrasonically guided biopsy if either of the initial studies is abnormal. Use of age-specific reference ranges for prostate-specific antigen results in greater sensitivity of this serum marker in patients below the age of 60 y and greater specificity in older patients.

Humans↗
PubMed1996

Serum prostate specific antigen levels after transurethral resection of prostate: a longitudinal characterization in men with benign prostatic hyperplasia.

PURPOSE: We studied the long-term effects of adenomectomy on serum levels of prostate specific antigen (PSA) in men with benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: A consecutive series of 82 men undergoing adenomectomy for BPH between 1990 and 1992 was studied. PSA levels were determined before and serially after operation for as long as 5 years. RESULTS: Mean PSA decreased from 4.6 ng/ml. preoperatively to 0.7 ng./ml. 6 months postoperatively. These low levels were maintained throughout the 5-year observation period. The PSA decrease correlated with grams of tissue removed (r = 0.54, p < 0.001) and averaged 0.11 ng./ml./gm. Postoperatively mean PSA velocity was 0.01 ng./ml. per year, that is essentially flat, and it was not influenced by patient age, race, type of operation, grams of tissue removed, baseline PSA, PSA density of T1a lesions (7). One to 5 years after adenomectomy 6 of the 82 men had invasive prostatic carcinoma, and PSA levels and velocities remained low. CONCLUSIONS: These data support the concept of transition zone primacy in determining serum PSA. Furthermore, they suggest a possible need for a modified reference range when using PSA to screen for prostatic carcinoma in the estimated 3 million men alive in the United States who previously underwent adenomectomy for BPH.

Adult↗
PubMed1996

Prospective evaluation of prostate specific antigen and prostate specific antigen density in the detection of nonpalpable and stage T1C carcinoma of the prostate.

PURPOSE: We evaluated prospectively prostate specific antigen (PSA) and prostate specific antigen density in the detection of prostate cancer in patients with normal findings on digital rectal examination with and without normal transrectal ultrasound. MATERIALS AND METHODS: Consecutive patients (184) with an elevated serum PSA and normal digital rectal examination underwent transrectal ultrasound with lesion directed and systematic biopsies (6 if prostatic volume was 50 cc or less and 12 if volume was more than 50 cc). Receiver operating characteristic curves, predictive values and likelihood ratios were calculated for PSA and PSA density. RESULTS: Of the 184 patients 50 (27%) with a normal digital rectal examination had cancer compared to 30 of 112 (27%) with a normal digital rectal examination and transrectal ultrasound. Median PSA or PSA density did not differ between the positive and negative biopsy groups among patients with a normal digital rectal examination (8.4 versus 7.1 and 0.22 versus 0.14 ng./ml., respectively) or a normal digital rectal examination and transrectal ultrasound (8.2 versus 7.5 and 0.21 versus 0.14 ng./ml., respectively). PSA density was superior to PSA by receiver operating characteristic analysis for cancer detection when all PSA values or those between 4 and 20 ng./ml. were considered. However, the significance was lost for a PSA of 4 to 10 ng./ml. Likelihood ratios demonstrated insignificant changes in the post-test probability if PSA density was used to determine the need for biopsy and many cancers would have been missed. CONCLUSIONS: PSA density should not be used to determine the need for biopsy in patients with a normal digital rectal examination and/or transrectal ultrasound.

Biopsy↗
PubMed1997

[Serum and urine prostate-specific antigen ratio: its value in the distinction between prostate cancer and adenoma when serum prostate-specific antigen level is between 4 and 10 ng/ml].

BACKGROUND: In an earlier study, we demonstrated that benign prostatic hyperplasia (BPH) was associated with significantly higher urine levels of prostate-specific antigen (PSA) than in prostate cancer (PC). These early results led to the present study: we assessed, in patients undergoing a prostate biopsy, the clinical value of the PSA serum/urine ratio (PSA S/U) in patients for the differential diagnosis of PC, particularly when the pre-biopsy serum level of PSA lies between 4.0 and 10.0 ng/ml. METHODS: All patients without an indwelling drain who underwent transrectal echoguided biopsy were prospectively included in this study from November 1994 to December 1995. All serum and urine PSA measurements were done by the same laboratory using a Tandem R kit (Hybritech). Blood and urine samples were obtained during the 24 hour period prior to surgery during which all urethral or rectal manipulation was avoided. RESULTS: We studied 130 patients with BPH (n = 73) or PC (n = 57). The PSA serum levels and the PSA S/U were significantly different between the BPH and the PC groups. In the subgroup of 50 patients with a serum PSA level in the 4-10 ng/ml range, the difference between the BPH and PC patients was not significantly different except for the PSA S/U ratio. Receiver operating characteristic (ROC) curves showed that the diagnostic power of PSA S/U was greater than serum PSA. CONCLUSION: These results suggest that the PSA S/U ratio could be useful to distinguish between BPH and PC, particularly when diagnosis is uncertain in patients whose serum PSA is in the 4.0-10.0 ng/ml range.

Aged↗
PubMed2004

Free and total prostate specific antigen in benign prostate hyperplasia and prostate cancer.

OBJECTIVE: To record the levels of PSA in the sera of prostate cancer (CaP) and benign prostatic hyperplasia (BPH) cases. Free PSA/total PSA as percentage was also calculated in order to evaluate its utility in differentially diagnosing BPH and CaP. DESIGN: A cross-sectional, case control study. PLACE AND DURATION OF STUDY: Shaikh Zayed Hospital and Mayo Hospital, Lahore from August 2002 to March 2003. MATERIALS AND METHODS: A group of 108 male subjects, including one-third of each of biopsy-confirmed prostate cancer cases, BPH cases and asymptomatic controls of matching age were studied. PSA and Free PSA were determined by ELISA using commercially available assay kits. RESULTS: Mean PSA was found to be highest in CaP cases (41.9 +/- 38.7 ng/ml), lower in the BPH cases (13.5 +/- 10.5 ng/ml), while it was lowest in the control subjects (5.7 +/- 4.4 ng/ml). Moreover, it was observed that a majority of the CaP cases had serum PSA >20 ng/ml, 50% of BPH cases had serum PSA in the 'gray zone' (4.1-20 ng/ml), while majority of controls had serum PSA in the 'normal' range (0 - 4 ng/ml). Using a free- PSA "cut-off" of 18% to differentiate between benign and malignant prostate enlargement, it was found that 80% of the CaP cases had F/T% <18, while 75% of the BPH cases had F/T%>18. The percent free-PSA test to differentially diagnose BPH and CaP in the 'gray zone' was found to have a sensitivity of 86% and a specificity of 94%. CONCLUSION: Using a cutoff of 18%, the free-PSA test significantly improved the differential diagnosis of BPH and CaP in the 'gray zone' as compared to the use of total PSA alone in the study group.

Aged↗
PubMed1997

Comparison of serum prostate specific membrane antigen, prostate specific antigen, and free prostate specific antigen levels in radical prostatectomy patients.

BACKGROUND: Higher preoperative prostate specific antigen (PSA) levels are associated with higher pathologic stage and grade in patients undergoing radical prostatectomy (RP). In earlier studies, serum prostate specific membrane antigen (PSMA) elevations were associated with clinical progression and hormone-refractory carcinoma. The goal of this study was to evaluate the serum markers PSMA, free PSA (FPSA), free:total PSA ratio (F:TPSA), and total PSA (PSA) in men undergoing RP. METHODS: Serum was obtained from 63 patients undergoing RP for clinically localized (T1c, T2) prostate carcinoma. Serum PSA and FPSA were determined by Hybritech Tandem-E(R) and Tandem-R(R), respectively, and PSMA was determined by Western blot analysis. Serum values for these markers were compared with the pathologic stage, surgical margin status, Gleason sum, prostate size (as calculated via reconstruction and transrectal ultrasound), tumor size based on pathologic assessment of the whole mount, and World Health Organization (WHO) grade of the prostatectomy specimen. Markers were also compared against demographic information and the patients' age and race. RESULTS: There was a weak correlation between serum PSA and positive surgical margins, higher Gleason sum, and WHO grade (P < 0.05). Receiver operating characteristic curve (ROC) analysis comparing sensitivity and specificity of the markers to positive and negative margins as well as seminal vesicle invasion demonstrated PSA and FPSA predictive ability for seminal vesicle invasion. The area under the curve for PSA and FPSA in this case was 0.7318 and 0.7432, respectively. There was also a weak correlation between the FPSA level and margins, with a low ROC area under the curve of 0.6789. The FPSA cannot distinguish the more advanced stage of disease. There was no significant correlation between F:TPSA and PSMA with regard to the study variables in predicting organ confinement. High PSMA levels only correlated with higher stage and were maximal in pT4a classified disease. CONCLUSIONS: Higher PSA and FPSA levels are likely to be associated with more locally advanced disease. Total PSA was the best marker. However, the cutoff values necessary for significant accuracy between PSA and FPSA are not of clinical usefulness due to the lack of specificity and sensitivity of the markers at those cutoffs. F:TPSA and PSMA levels as currently measured are of limited value in discriminating more aggressive disease in patients with clinically localized CaP.

Aged↗
PubMed2004

Algorithms based on prostate-specific antigen (PSA), free PSA, digital rectal examination and prostate volume reduce false-positive PSA results in prostate cancer screening.

Our objective was to determine whether multivariate algorithms based on serum total PSA, the free proportion of PSA, age, digital rectal examination and prostate volume can reduce the rate of false-positive PSA results in prostate cancer screening more effectively than the proportion of free PSA alone at 95% sensitivity. A total of 1,775 consecutive 55- to 67-year-old men with a serum PSA of 4-10 microg/l in the European Randomized Study of Screening for Prostate Cancer were included. To predict the presence of cancer, multivariate algorithms were constructed using logistic regression (LR) and a multilayer perceptron neural network with Bayesian regularization (BR-MLP). A prospective setting was simulated by dividing the data set chronologically into one set for training and validation (67%, n = 1,183) and one test set (33%, n = 592). The diagnostic models were calibrated using the training set to obtain 95% sensitivity. When applied to the test set, the LR model, the BR-MLP model and the proportion of free PSA reached 92%, 87% and 94% sensitivity and reduced 29%, 36% and 22% of the false-positive PSA results, respectively. At a fixed sensitivity of 95% in the test set, the LR model eliminated more false-positive PSA results (22%) than the proportion of free PSA alone (17%) (p < 0.001), whereas the BR-MLP model did not (19%) (p = 0.178). The area under the ROC curve was larger for the LR model (0.764, p = 0.030) and the BR-MLP model (0.760, p = 0.049) than for the proportion of free PSA (0.718). A multivariate algorithm can be used to reduce unnecessary prostate biopsies in screening more effectively than the proportion of free PSA alone, but the algorithms will require updating when clinical practice develops with time.

Aged↗
PubMed1980

Comparison of the R-3327H rat prostatic adenocarcinoma to human benign prostatic hyperplasia and metastatic carcinoma of the prostate with regard to steroid hormone receptors.

Quantitative analyses of cytosolic steroid hormone receptors were performed on nine tumors from the transplantable rat prostatic adenocarcinoma R-3327H. Androgen receptors and estrogen receptors were found in eight of nine and five of six tumors, respectively. None of the tumours analyzed contained detectable progestin or glucocorticoid receptors (four and seven tumors, respectively). The apparent equilibrium dissociation constants for the androgen and estrogen receptors were 0.7-4.3 nM and 0.6-1.8 nM, respectively. The apparent equilibrium Bmax values (maximum number of binding sites) were 1,500-25,000 fmoles/gm tissue for the androgen receptor and 640 to 5,800 fmoles/gm tissue for the estrogen receptor. A comparison between the receptor contents of the R-3327H rat tumor and human benign prostatic hyperplasia and metastatic carcinoma of the prostate showed that the rat tumor was different from the human tissues in several respects. Hence, the search for an optimal animal model for prostatic carcinoma in man must be continued.

Adenocarcinoma↗