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Query: UMLS:C0376358 (prostate cancer)
 59,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Prostate specific antigen (PSA), neutral serine protease secreted exclusively by prostatic epithelial cells, has a number of applications in the management of men with prostatic carcinoma. While it is widely recognized that elevated PSA correlates with the presence of carcinoma, little data exist regarding the use of PSA as the initial test in the early detection of prostatic cancer. We measured serum PSA levels in men older than 50 years and performed digital rectal examination and ultrasound guided prostate biopsy of those who had a PSA level of greater than 4.0 ng./ml. A total of 1,249 men entered the protocol, of whom 187 (15.0%) had PSA levels above 4.0 ng./ml. Digital rectal examination and ultrasound guided biopsy were performed at our facility in 105 patients (56.2%). A total of 32 carcinomas (30.5%) was detected, including 23 in men with PSA between 4.1 and 10.0 ng./ml. and 9 in men with a PSA of greater than 10.0 ng./ml. Of the 32 carcinomas 12 (37.5%) occurred in men with normal prostates or glands demonstrating only asymmetry on digital rectal examination, and 3 men had carcinoma despite normal digital rectal examination and no hypoechoic peripheral zone lesion detected on ultrasound. Of the 32 patients 30 had clinically localized carcinoma but 7 of the 16 undergoing radical prostatectomy had pathological upstaging. We conclude that PSA represents an important adjunct to digital rectal examination for the early detection of prostatic carcinoma. The efficacy of this or any other early detection test to decrease prostate cancer mortality necessitates the results of prospectively randomized clinical trials.
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PMID:Screening for prostatic carcinoma with prostate specific antigen. 137 59

Prostate specific antigen (PSA) has become a mainstay in the diagnosis and management of patients with prostate cancer. We have found, as have others, that it may be elevated in patients with prostatic inflammation. Ten patients had clinical evidence of prostatitis and elevated PSA levels. Six of these had persistently elevated levels after antibiotic treatment. After transrectal ultrasonography and biopsy, two had findings of adenocarcinoma, and the rest had a pathologic diagnosis of acute or chronic prostatitis. We studied this process in an experimental model of prostatitis using a nonhuman primate. We infected six cynomolgus monkeys and followed their PSA levels until resolution of the infection. The PSA peaked between 5 and 7 days after inoculation and gradually returned to baseline in 8 weeks. The dramatically elevated serum PSA levels in bacterial prostatitis can cause confusion in the diagnosis of prostatic carcinoma.
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PMID:Prostate specific antigen and prostatitis. I. Effect of prostatitis on serum PSA in the human and nonhuman primate. 137 26

Prostate specific antigen (PSA) is the most useful serum marker for following the disease status of prostate cancer patients after therapy. While PSA is felt to be an organ specific marker, lack of PSA expression in the seminal vesicles has not been adequately established. MHS-5 is a monoclonal antibody which recognizes an epitope on seminal vesicle specific antigen. Our objectives were to define PSA expression by the seminal vesicles, to determine whether MHS-5 could serve as an adjunct in the diagnosis of seminal vesicles invasion by carcinoma of the prostate, and to determine whether carcinoma, having invaded seminal vesicles would retain its expression of PSA and other prostate markers. Using an immunoperoxidase procedure, we studied thirteen seminal vesicles without histologic evidence of prostate cancer invasion and five seminal vesicles with locally invasive cancer. No seminal vesicles expressed PSA, whereas prostate cancer invading the seminal vesicles expressed PSA in all cases. MHS-5 expression was more variable. Only two of five cases of locally invasive tumor demonstrated seminal vesicles expression for MHS-5. Our findings further support the specificity of PSA. While MHS-5 may be helpful in delineating seminal vesicles in some instances, it is not a consistently reliable marker.
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PMID:The detection of prostate specific antigen, MHS-5, and other markers in invasive prostate cancer and seminal vesicle. 137 81

Prostate specific antigen (PSA) has replaced prostatic acid phosphatase as the preeminent clinical tumor marker in the management of patients with prostate cancer. Serum PSA levels have been shown to be proportional to clinical and pathologic stage of prostate cancer and in particular to correlate closely with prostate cancer volume. Serum levels of PSA thus serve as a useful adjunct in the initial clinical staging of men with prostate cancer. Serum PSA values provide a unique and valuable tool in monitoring prostate cancer progression over time and its response to surgical, radiation, and/or hormonal therapies. Unfortunately, its lack of specificity for prostate cancer leaves many questions unanswered as to the efficacy and advisability of using PSA as a screening test for this cancer.
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PMID:Prostate specific antigen: clinical use in the diagnosis and management of prostate cancer. 138 Sep 41

With the increasing incidence of carcinoma of the prostate, the interest in early diagnosis through screening has dramatically increased. Several organizations, including the American Urological Association (AUA) and the American Cancer Society, have promulgated recommendations on suggested early detection methods. To determine the current practice patterns of United States urologists, a survey was sent to a random sample of 10% of all urologist members of the AUA. The survey was designed to determine what are current recommendations for an annual urological checkup for older men, what tests should be included in screening for carcinoma of the prostate and what age groups of men should undergo prostate cancer screening. A total of 562 surveys was returned, constituting a 4.7% sample of all urologist members of the AUA. The use of digital rectal examination was unanimously recommended for the urological examination as well as for prostate cancer detection. Prostate specific antigen was recommended by a majority of respondents for both situations. Screening was recommended for men ages 50 to 80 years. Demographic factors had a significant role in clinical recommendations by urologists.
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PMID:Current urological practice: routine urological examination and early detection of carcinoma of the prostate. 163 28

Prostate specific antigen (PSA) levels were determined in 78 patients judged clinically to be free of disease at intervals of 36 or more months (range 38 to 186 months, median 87 months) after completion of irradiation therapy by 125iodine implantation or external beam radiation. Of this select group of patients 38% had undetectable serum PSA levels (0.5 ng./ml. or less) and 38% had PSA levels that were within normal limits (4.0 ng./ml. or less). All stages and grades were represented. Undetectable PSA levels were only rarely found (3%) in patients with carcinoma of the prostate before treatment. In 24 of these 78 patients a negative biopsy of the irradiated prostate had been obtained 18 to 42 months after treatment. When the PSA level was drawn, which ranged from 7 to 16 years after treatment, an equal percentage of these biopsied patients had either an undetectable, normal or elevated level. Irradiation is able to decrease PSA to undetectable levels in some patients with prostatic carcinoma. Whether this reflects suppression of marker production alone or, more importantly, ablation of prostate cancer producing that marker remains to be determined.
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PMID:Prostate specific antigen levels after definitive irradiation for carcinoma of the prostate. 170 87

Prostate specific antigen levels were measured in 118 patients with prostatic cancer and 138 control individuals. Prostate specific antigen was sensitive in detecting prostatic cancer. The levels of prostate specific antigen were elevated in 10 per cent of the patients with stage A, 24 per cent with stage B, 53 per cent with stage C and 92 per cent with stage D disease. However, prostate specific antigen levels also were elevated in 9 per cent of the patients with benign prostatic hypertrophy. This lack of specificity in the presence of benign prostatic hypertrophy probably precludes prostate specific antigen from being recommended as a screening test for prostatic cancer. The ultimate role of prostate specific antigen might be as the marker of choice to monitor therapy for prostatic carcinoma.
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PMID:An evaluation of prostate specific antigen in prostatic cancer. 243 27

The usefulness of prostate specific antigen to predict final pathological stage was studied in 178 consecutive patients. Prostate specific antigen was determined preoperatively in all patients by a monoclonal immunoradiometric assay. All pathological specimens were examined for capsular penetration, seminal vesicle involvement and lymph node involvement. Prostate specific antigen correlated directly with capsular penetration (p less than 0.002), seminal vesicle involvement (p less than 0.02) and lymph node involvement (p less than 0.05). However the diagnostic accuracy of an elevated serum antigen level on an individual basis was only 55 per cent for capsular penetration and 50 per cent for seminal vesicle involvement and lymph node involvement. With a log-linear regression model, the half-life of prostate specific antigen was calculated to be 3.15 +/- 0.09 days. From the equation PSA (t) equals PSA (2) e[-0.2197(t-2)], prostate specific antigen can be used to detect residual cancer on day t in the immediate postoperative period. With respect to long-term followup, 127 patients have been monitored for longer than 2 months postoperatively with prostate specific antigen (mean followup 2 years, range 2 months to 8.6 years). Of the 101 patients who had favorable pathological findings at operation (organ-confined cancer or capsular penetration only) 92 (91 per cent) had a followup antigen concentration in the female range (0.0 to 0.2 ng. per ml.), whereas only 5 of 26 men (19 per cent) with either seminal vesicle involvement or lymph node involvement had an antigen value that was less than 0.2 ng. per ml. All patients with a documented clinical recurrence (8 of 127, 6 per cent) had an elevated followup serum prostate specific antigen concentration. These findings suggest that preoperative levels of prostate specific antigen are not sufficiently reliable to predict final pathological stage on an individual basis in patients with early prostatic cancer, and that the antigen is a sensitive tumor marker for the detection of residual disease after radical prostatectomy and subsequent recurrence of tumor on long-term followup.
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PMID:Prostate specific antigen in the preoperative and postoperative evaluation of localized prostatic cancer treated with radical prostatectomy. 245 Oct 37

Serum prostate specific antigen was determined (Yang polyclonal radioimmunoassay) in 102 men before hospitalization for radical prostatectomy. Prostate specimens were subjected to detailed histological and morphometric analysis. Levels of prostate specific antigen were significantly different between patients with and without a Gleason score of 7 or greater (p less than 0.001), capsular penetration greater than 1 cm. in linear extent (p less than 0.001), seminal vesicle invasion (p less than 0.001) and pelvic lymph node metastasis (p less than 0.005). Prostate specific antigen was strongly correlated with volume of prostate cancer (r equals 0.70). Bivariate and multivariate analyses indicate that cancer volume is the primary determinant of serum prostate specific antigen levels. Prostate specific antigen was elevated 3.5 ng. per ml. for every cc of cancer, a level at least 10 times that observed for benign prostatic hyperplasia. Prostate specific antigen is useful as a preoperative marker because no patient with lymph node metastasis had serum levels of less than 10 ng. per ml. (4 times the upper limit of normal range). Of the patients with greater than 50 ng. per ml. two-thirds had microscopic lymph node metastasis and 90 per cent had seminal vesicle invasion. Serum prostatic acid phosphatase levels showed a significantly weaker correlation with cancer volume (r equals 0.51) and every other pathological parameter. Of the patients 73 per cent had serum prostatic acid phosphatase levels in the normal range (0 to 2.1 ng. per ml.), including 7 per cent who had pelvic lymph node metastasis. Postoperative prostate specific antigen values were available in 97 of 102 patients, with a mean and maximum followup of 12 and 38 months. No patient with pelvic lymph node metastasis achieved an undetectable prostate specific antigen level without adjunctive therapy (hormonal or radiation). No difference in preoperative or postoperative prostate specific antigen levels, cancer volume, seminal vesicle invasion or incidence of pelvic lymph node metastasis was seen between patients with no capsular penetration and those with minimal capsular penetration (1 cm. or less total linear extent of full thickness penetration), providing the first quantitative evidence that small amounts of capsular penetration may not be of biological or prognostic significance.
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PMID:Prostate specific antigen in the diagnosis and treatment of adenocarcinoma of the prostate. II. Radical prostatectomy treated patients. 246 95

Prostate specific antigen was not detectable in 2 men with documented prostate cancer progression after radical prostatectomy. Possible explanations for prostate specific antigen remaining zero in these situations are discussed. We conclude that while monitoring prostate specific antigen is of great value in the followup of patients with prostatic cancer, it has not replaced more standard means of followup.
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PMID:Prostate specific antigen: not detectable despite tumor progression after radical prostatectomy. 247 60


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