Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0376358 (prostate cancer)
 59,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Noninvasive methods for the diagnosis of prostatic cancer, its staging and evaluation of response to therapy are often not sufficiently sensitive or specific. Prostate-specific antigen (PSA) was identified in 1979 and has been evaluated since then as a marker, both at the serum and the tissue level. A review is presented in this article. PSA is an organ-specific glycoprotein presented in most prostatic carcinomas, but also in normal prostatic tissue and in benign prostatic hypertrophy (BPH). The monitoring of serum PSA concentrations by serial measurement can be used for the detection of residual or recurrent tumor after primary treatment and for the evaluation of response to systemic treatment of advanced disease. At the tissue level immunohistochemical detection of PSA may help to identify metastatic tumor of unknown origin. PSA serum assays have not been sufficiently sensitive and specific for staging of the primary tumor or for screening purposes. PSA is an equally specific, but more sensitive marker of prostatic carcinoma compared to prostatic acid phosphatase.
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PMID:Prostate-specific antigen (PSA). A tissue-specific and sensitive tumor marker. 168 77

We studied 103 patients seen in our Prostate Cancer Detection Clinic to determine whether a correlation exists between serum prostate-specific antigen (PSA) values and ultrasound-calculated prostate gland volume. Seventy men (68%) had a PSA value less than or equal to 4 ng/ml (our upper limit of normal). The men were subclassified by prostate gland volume at arbitrary break points. Twenty-five men (24%) had a prostate gland volume less than or equal to 25 cm3; in 96%, the PSA value was less than or equal to 4 mg/ml. Further analysis revealed that the percentage of men with a normal serum PSA value decreased as the prostate gland volume increased; 65.6% of the group with a gland volume between 25 and 50 cm3 (40 of 61) and 35.5% of the group whose prostate volume exceeded 50 cm3 (6 of 17) had PSA values less than or equal to 4 ng/ml. Four men had PSA values greater than 20 ng/ml; all had prostate cancer. Cancer was diagnosed in four additional patients, three with PSA values between 5 and 10 ng/ml and one with a PSA value less than 4 ng/ml. There appears to be a direct relationship between prostate gland volume and PSA value, as well as a cancer value threshold. The clinical implications of these findings are discussed.
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PMID:Prostate-specific antigen and prostate gland volume: correlation and clinical application. 170 82

A study was performed on 175 men to compare the level of prostate-specific antigen (PSA) in patients with benign prostatic hyperplasia (n = 83) and prostatic carcinoma (n = 92). There was a good correlation between T stage and increasing values of PSA. Using 2.5 ng/ml as the upper normal limit of PSA, the test sensitivity of PSA was 94%, but the specificity only 44%. Receiver-operator characteristic curve (ROC) analysis demonstrates that PSA is superior to prostatic acid phosphatase (PAP); this is particularly true in the higher T stages. Although ROC analysis shows that PSA is more discriminating than PAP, the sensitivity of PSA is dependent upon the choice of an appropriate cut-off point of the test. It was shown that PSA is not sufficient for detecting the presence or absence of prostatic cancer in a general population. However, PSA is the most sensitive marker in the detection of prostatic cancer.
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PMID:Efficacy and discriminative ability of prostate-specific antigen as a tumor marker. 169 Jun 53

Recent advances in the diagnosis and treatment of patients with prostate cancer have altered clinical management of the disease. Although direct rectal examination remains the standard clinical tool for staging prostate cancer, transrectal ultrasound appears to be about twice as sensitive for detection. Prostate-specific antigen (PSA) has replaced prostate-specific acid phosphatase as a serum tumor marker for prostate cancer. When used in conjunction with measurement of prostate volume by transrectal ultrasound, PSA values may identify patients at increased risk for occult cancer. Use of transrectal ultrasound and PSA values has also improved the accuracy of clinical staging. Modifications in the technique of radical prostatectomy have minimized the morbidity associated with this procedure, making it a more attractive therapeutic option in patients with localized prostate cancer. In patients with metastatic disease, total androgen blockade is an option that appears superior to standard hormonal therapy.
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PMID:Prostate cancer. Promising advances that may alter survival rates. 169 Aug 83

The effect of external beam radiation on serum prostate-specific antigen (PSA) was determined in 20 patients with nonmetastatic carcinoma of the prostate. An abnormal PSA was measured in 91 percent and 93 percent, respectively, of the samples collected prior to or during radiation therapy. By seven months, 8/15 men still had an abnormal PSA level. Four of 5 men with an elevated PSA at least twenty-three months after radiation therapy had a positive prostatic biopsy, and 3/3 patients with a normal PSA had a negative ultrasonically guided biopsy. The rate of decline of serum PSA after radiation therapy is variable. These preliminary data suggest that serum PSA may be useful for assessing the local response of prostate cancer to radiation therapy.
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PMID:Effect of external beam radiation therapy on serum prostate-specific antigen. 169 Sep 36

The isolation and purification of prostate-specific antigen (PSA) and the development of a radioimmunoassay for this antigen represent major advancements for the detection of adenocarcinoma of the prostate and the monitoring of response to therapy in patients with this disease. Both monoclonal and polyclonal assays for PSA are available. In attempts to correlate pathologic tumor stage and PSA levels, tumors of higher stage (pathologic stages C1, C2, D1, and D2) have been associated with elevated PSA levels. Increased PSA levels have also been found in patients with benign prostatic diseases (benign prostatic hypertrophy and prostatitis). PSA has been shown to be an excellent marker after radical prostatectomy and for monitoring of radiation therapy. Patients with a persistently elevated PSA level for more than 6 months postoperatively should be assessed for residual or recurrent local or systemic disease. Thus far, routine use of PSA testing as a mass screening modality for prostatic cancer has not been considered cost-effective.
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PMID:Prostate-specific antigen testing in untreated and treated prostatic adenocarcinoma. 169 14

Serum prostate-specific antigen (PSA) levels were studied in the EORTC trial of zoladex plus flutamide versus orchidectomy in metastatic prostatic cancer. Forty-four of 60 patients had a decrease of PSA to less than or equal to 10 ng/ml at 3 to 6 months after treatment. The combination of a PSA less than 10 ng/ml after 3 to 6 months treatment and less than 15 spots on the bone scintigram at entry gave the highest probability of not having progressed by 24 months. A rising PSA anticipated bone progression by 6 to 12 months in 13 of 28 patients (46%). The PSA at entry to the trial was related to survival; a discriminant of 300 ng/ml distinguished a poor and better risk group. The lowest level of PSA reached during the first 6 months of treatment was also a univariate survival factor.
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PMID:Prostatic specific antigen and the prediction of prognosis in metastatic prostatic cancer. 169 98

A total of 58 cases with prostatic diseases including benign hypertrophy (BPH) (n = 10) and adenocarcinoma (n = 48) were studied as to prostate-specific antigen (PA) with indirect enzyme immunohistochemistry. The expression of PA in the prostate, as well as the localization of PA in the tissue, was also studied in regard to cell differentiations, clinical stages, serum PA levels, with or without endocrine therapy, and prognosis of prostate cancer. Strong staining of PA was noted in epithelial cells of the gland, particularly on the ductal cavity, except for patients in the poorly differentiated carcinoma group. The overall positive rate for expression of PA was 100% in BPH and 73% (35/48) in prostate cancer. When prostate cancer was classified by cell differentiation, the positive rate was 100% (17/17) in the patients with well, 83% (10/12) moderately, and 42% (8/19) poorly differentiated carcinoma. When divided by clinical stages, the positive rate was 100% (1/1 and 9/9) in stages A and B each, 69% (9/13) in stage C, and 65% (17/26) in stage D. Of 33 cases whose serum PA values were determined, the histochemistry was positive in 67% of 12 patients with normal serum PA levels and in 86% of 21 in the elevated group. The prior to endocrine therapy group showed the presence of PA in 22 of 27 cases (82%) and a positive rate of 62% (13/21) was observed in the group during the treatment.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[The histological expression of prostate-specific antigen and its clinical significance in patients with prostate cancer]. 169 32

Acid phosphatase and prostate-specific antigen are extremely useful markers for the management of patients with prostatic carcinoma. Prostatic acid phosphatase, because of its relatively low sensitivity and specificity, as well as analyte instability and diurnal variability, is unsuitable for prostate cancer screening. Improved performance characteristics, stability, the lesser diurnal variation, and the association of elevated prostate-specific antigen with prostatic intraepithelial neoplasia make prostate-specific antigen possibly a better candidate for early detection of this common malignancy. Further investigations in this area are clearly indicated before we can recommend screening with prostate-specific antigen.
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PMID:Laboratory studies for the detection of carcinoma of the prostate. 169 41

Thirty-one patients with bidimensionally measurable hormone-refractory prostatic cancer received trimetrexate (TMTX). Serial values of prostate-specific antigen (PSA) and acid phosphatase (SAP) were correlated with response. Five patients (17%; 95% confidence interval, 3% to 30%) achieved a partial remission for a median of 3 months (range, 3 to 7.5 months). Marker levels showed large variations with no discernible patterns. Serial PSA and SAP in 19 patients with abnormal baseline values showed a correlation with measurable disease response in only 68% (13 of 19) and 47% (nine of 19) of patients, respectively. Values were then smoothed using an exploratory data analysis technique of running medians and averages. Trends in marker changes were much more apparent. Several "decision rules" were evaluated for use of markers as indices of disease progression. A 50% increase from the patient's minimum value in either PSA or SAP on two successive determinations correlated with progression in 90% of cases in this trial. TMTX has modest activity in prostatic cancer, and further trials are not warranted. Biochemical markers do not uniformly reflect disease activity in hormone-refractory disease, and changes in biochemical markers must be interpreted cautiously when used as the sole end point to assess efficacy in clinical trials.
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PMID:Trimetrexate in prostatic cancer: preliminary observations on the use of prostate-specific antigen and acid phosphatase as a marker in measurable hormone-refractory disease. 170 78


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