Nontraumatic elevation of prostate specific antigen following cardiac surgery and extracorporeal cardiopulmonary bypass

Factors influencing blood tumor marker concentrations in the absence of neoplasia

BACKGROUND

Tumor markers (TMs) are a heterogeneous group of molecules used in the diagnosis, prognosis and follow-up of cancer patients. During neoplastic differentiation, cells can either directly synthesize or induce the synthesis of TMs, and the release of these molecules into the bloodstream allows their quantification in biological fluids. Although very small concentrations of TMs are usually present in the serum or plasma of healthy subjects, increased concentrations may also be found in the presence of benign diseases or due to technical interference, producing false positive results.

MATERIAL AND METHODS AND RESULTS

Our review analyses the causes of false positives described between January 1970 to February 2023 for the TMs most frequently used in clinical practice: α-fetoprotein (AFP), β2-microglobulin (β2-M), cancer antigen 15-3 (CA 15-3), cancer antigen CA 19-9 (CA 19-9), cancer antigen CA 72-4 (CA 72-4), cancer antigen 125 (CA 125), carcinoembryonic antigen (CEA), chromogranin A (CgA), choriogonadotropin (hCG), cytokeratin 19 fragment (CYFRA 21-1), neuron-specific enolase (NSE), human epididymis protein 4 (HE4), serum HER2 (sHER2), squamous cell carcinoma antigen (SCCA), protein induced by vitamin K absence-II (PIVKA-II), Pro-gastrin-releasing peptide (Pro-GRP), prostate-specific antigen (PSA), Protein S-100 (S-100) and thyroglobulin (Tg). A total of 247 references were included.

CONCLUSIONS

A better understanding of pathophysiological processes and other conditions that affect the concentration of TMs might improve the interpretation of results and their clinical application.

Perioperative prostate specific antigen levels among coronary artery bypass grafting patients: Does extracorporeal circulation and body temperature induce prostate specific antigen levels alterations?

Purpose:

The purpose of this study is to compare the perioperative total prostate specific antigen (tPSA) levels among coronary artery bypass grafting (CABG) patients with and without extracorporeal circulation (ECC), to investigate the changes overtime of tPSA in each group separately and to determine the effect of body core temperature on tPSA levels.

Materials and Methods:

A prospective study was conducted. Our sample was allocated to: (a) Seven patients who underwent off pump CABG (Group I) and (b) 16 CABG patients with ECC (Group II). The levels of tPSA were measured preoperatively (baseline), intra-operatively and at the 4^th postoperative day. We compared the two groups on their tPSA levels and we investigated the changes of tPSA overtime in each group separately.

Results:

Intra-operative serum samples were obtained in significantly lower body temperature in patients of Group II than in those of Group I (31°C vs. 36.9°C, P < 0.001). In each group separately, postoperative tPSA levels were increased significantly compared to the baseline values (2.55 ng/ml vs. 0.39 ng/ml for Group I, P = 0.005 and 4.36 ng/ml vs. 0.77 for Group II, P < 0.001). CABG patients with ECC had significantly lower intra-operative tPSA levels than the baseline values (0.67 ng/ml vs. 0.77 ng/ml, P = 0.008). We did not observe significant differences of tPSA levels between the two groups.

Conclusions:

CABG surgery affects similarly the perioperative tPSA independently the involvement of ECC. Although all patients had significantly higher early postoperative tPSA levels, only those who underwent CABG with ECC had exceeded normal values and significantly decreased intra-operative tPSA. Hypothermia seems to be the causal factor of tPSA reduction.

Effect of constipation on serum total prostate-specific antigen levels in men

OBJECTIVES

Many factors affecting serum prostate-specific antigen (PSA) levels have been described. The aim of this study was to examine the effect of constipation on serum PSA levels in men.

METHODS

Serum total PSA values were measured in 136 constipated patients before and after treatment for constipation. Moreover, they were compared with 45 control patients.

RESULTS

Serum total PSA values in the constipated patients before treatment were significantly higher than those in the control group (2.29 ± 1.29 ng/mL vs 1.28 ± 0.86 ng/mL, P < 0.0001). After the treatment of constipation, serum total PSA values in the constipated patients were still higher than those in the control group, but this difference was not statistically significant (P = 0.0871). After the treatment of constipation, prostate biopsy rates were 6.6% and 2.2% in the study and control group, respectively (P = 0.2769). No prostate cancer was found in both groups.

CONCLUSIONS

Constipation increases serum PSA levels in men. The presence of constipation must be considered in patients whose PSA is examined, especially in those with PSA levels that are borderline high or in the range of 2-10 ng/mL. Constipated patients must be first treated and then re-evaluated.

Prostate-specific antigen levels are associated with arterial stiffness in essential hypertensive patients

INTRODUCTION

Prostate-specific antigen (PSA) has been recently related to cardiovascular system in a multifactorial way. Arterial stiffness is a independent predictor of cardiovascular events and is involved in the pathogenesis of hypertension. The aim of the present study was to investigate whether PSA values, are associated with arterial stiffness indices in patients with essential arterial hypertension.

METHODS

The study comprised 150 consecutive male patients (mean age 60 years) with uncomplicated never-treated essential hypertension. All patients underwent a complete clinical and laboratory evaluation, including measurement of PSA levels. Aortic stiffness and arterial wave reflection assessment was made by using carotid-femoral (PWVc-f) pulse wave velocity and aortic augmentation index corrected for heart rate (AIx75). Patients with prostate cancer or benign prostate hyperplasia (PSA > 4 ng/mL) were excluded from the study.

RESULTS

PSA was positively associated with waist-to-hip ratio (r = 0.235, P = 0.04), PWVc-f (r = 0.426, P < 0.001), AIx75 (r = 0.264, P = 0.001), and high sensitivity C-reactive protein (hsCRP; r = 0.376, P < 0.001). In categorization to PSA quartiles, patients in the higher quartile presented with higher waist-to hip ratio (P = 0.009), PWVc-f (P < 0.00001), AIx75 (P < 0.001) and hsCRP (P < 0.001) values. In multivariate analysis after adjustment for various confounders PSA remained a significant determinant of PWVc-f values (beta [SE] = 0.477 [0.13], R(2) = 0.405, P < 0.001).

CONCLUSION

The present study points towards an association between PSA levels and aortic stiffness in untreated essential hypertensive males. Potential causal relationships between PSA and arterial stiffness remain to be further explored.

Prostate-specific antigen kallikrein and the heart

Currently, there is growing interest regarding prostate-specific antigen (PSA) and the cardiovascular system. Increased PSA serum levels have been reported after prolonged cardiopulmonary resuscitation, cardiac surgery, extracorporeal cardiopulmonary bypass, acute myocardial infarction (AMI) and coronary artery stenting. The possible role of PSA in cardiac events has been questioned due to the finding of PSA decrease during AMI and by the correlation of variation in PSA levels with coronary lesions and occurrence of major adverse cardiac events. Complexed PSA forms and uncomplexed PSA forms are observed in the bloodstream but the increasing formation of irreversible bound PSA seems to be a crucial finding during AMI. Large studies need to be carried out to confirm these preliminary results and to elucidate unclear aspects. These findings present many potential directions for future research including the role of uncomplexed forms of PSA, the possible distribution of PSA in the heart, the relative expression levels in heart disease states, the mode of expression regulation and other potential specific substrates. The journey of PSA investigation could be longer than initially expected.

Prostate-specific antigen kallikrein complexes and acute myocardial infarction

Recently, attention has focused on prostate-specific antigen kallikrein and the cardiovascular system. The finding of diminished PSA during acute myocardial infarction and the correlation of variation of PSA with coronary lesions and occurrence of major adverse cardiac events have opened a possible new intriguing scenario. As with many stories in biology, the tale of PSA can be more complex than was first appreciated. In the bloodstream, the proteolytic activity of PSA is inhibited by the formation of irreversible complexes with serum protease inhibitors and other acute-phase proteins. We noticed that the formation of irreversible PSA complexes (reflected by the increased bound PSA) has significant correlation with high-sensitivity C-reactive protein (hsCRP) and that seems to play a crucial role in the adverse event prevention.

Prostate-specific antigen kallikrein: from prostate cancer to cardiovascular system

Prostate-specific antigen (PSA), considered only an established marker for the detection of prostate cancer, has been identified as a member (hK3) of the human kallikrein family of serine proteases and now, it is known that PSA is not specific to prostate, semen, and gender. Increased PSA serum levels have been reported also in cardiovascular patients and both elevated as well as diminished PSA have been reported during acute myocardial infarction (AMI). Preliminary observations have concluded that when elevation of prostate-specific antigen occurs during AMI, it seems to relate to a higher occurrence of major adverse cardiac events and that coronary lesions are frequent and often more severe than when a diminution of PSA occurs. Large studies need to be done to confirm these preliminary results but the journey of PSA could be longer than expected.

Prostate-specific antigen kallikrein and acute myocardial infarction: where we are. Where are we going?

Prostate-specific antigen (PSA) is an established marker for the detection of prostate cancer. Both elevated and diminished PSA have been reported during acute myocardial infarction. It seems that when elevation of PSA occurs during acute myocardial infarction (AMI), coronary lesions are frequent and often more severe than when a diminution of PSA occurs. PSA has been identified as a member of the human kallikrein family of serine proteases. In recent years, numerous observations have suggested that the activity of the kallikrein-kinin system is related to inflammation and to cardiovascular diseases. PSA kallikrein, however, does not seem to have kinin-generating activity. The inactive precursor form of PSA, proPSA, is converted rapidly to active PSA by Human kallikrein 2 (hK2), suggesting an important in vivo regulatory function byhK2 on PSA activity. However, it has been reported that hK2 might not alone be able to activate proPSA in vivo, but there are also other protease/proteases involved in this event. Moreover, it seems that when elevation of prostate-specific antigen occurs during AMI, it seems to relate to a higher occurrence of major adverse cardiac events in the first 8 days after AMI than when a diminution of PSA occurs. It confirms a possible new intriguing scenario of the role of the PSA in AMI. Although these preliminary observations are suggestive, large studies need to be done to confirm these preliminary results.

Influence of cardiopulmonary resuscitation on levels of tumour markers

Tumour markers (TM), including alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), cancer antigen (CA) 15-3 and prostate-specific antigen (PSA), are serum markers for malignant diseases. Previous studies investigating the effect of acute and chronic inflammation, cardiopulmonary bypass surgery and cardiopulmonary resuscitation (CPR) on levels of TM showed conflicting results. Cardiopulmonary resuscitation (CPR) may result in a profound inflammatory response, and is frequently associated with severe tissue hypoperfusion. The present study investigated whether AFP, CEA, CA 15-3 and PSA are influenced by CPR. Alpha-fetoprotein (AFP), CEA, CA 15-3 and PSA (only in male patients) were assessed immediately after hospital admission, 6 h, 12 h and 2 days after prolonged CPR in eight male and 12 female patients. Serum levels of AFP, CEA, CA 15-3 did not change significantly after CPR. Prostate-specific antigen (PSA) levels increased significantly with a highest level in the study period 48 h after CPR (3.3 +/- 3.1 and 28.3 +/- 30.5 ng/mL for baseline and 48 h levels, respectively; P < 0.001). Alpha-fetoprotein (AFP), CEA, CA 15-3 and PSA (in men) values above the normal range were observed in 0%, 13.8%, 3.8% and 46.9% of all measurements respectively. At least one value above the normal range were observed in 0%, 20%, 5% and 75% of all patients for AFP, CEA, CA 15-3 and PSA (in men) respectively. Baseline values of AFP, CEA, CA 15-3 and PSA (in men) were above the normal range in 0%, 15%, 5% and 10% of all patients respectively. Levels for all markers did not differ significantly between survivors and non-survivors. In conclusion, prolonged CPR does not influence AFP, CEA, CA 15-3 serum levels, but is frequently associated with increases of PSA. Thus, in contrast to PSA, interpretation of AFP, CEA, CA 15-3 serum levels is not influenced by recent CPR.

Comparison of the effects of on-pump versus off-pump coronary artery bypass surgery on serum prostate-specific antigen levels

AIM

To compare the effects of coronary artery bypass operation with or without extracorporeal circulation on serum total prostate-specific antigen levels.

METHODS

Seventy-six men with a mean age of 57.04+/-9.27 years (range 44-77 years), who underwent coronary artery bypass surgery were enrolled to the study. In 50 patients (Group I), coronary revascularization was performed using extracorporeal circulation, and in 26 patients (Group II) coronary bypass grafting was performed on the beating heart without using extracorporeal circulation. All the patients had serum total prostate-specific antigen levels measured preoperatively and twice postoperatively in the first and fifth postoperative days. Differences in mean total prostate-specific antigen levels between the two groups in the postoperative period were analysed.

RESULTS

The mean preoperative total prostate-specific antigen levels in Group I and Group II were 1.28+/-1.13 ng/mL and 1.11+/-0.93 ng/mL, respectively, and there was no significant difference in the preoperative total prostate-specific antigen values between the two groups (P=0.519). In Group I, postoperative means were 4.96+/-6.29 ng/mL and 5.86+/-9.09 ng/mL in the first and fifth days, respectively (P=0.0001, P=0.0001). Total prostate-specific antigen means in the same postoperative period for Group II were 2.13+/-2.72 ng/mL and 2.00+/-2.20 ng/mL, respectively (P=0.014, P=0.024). The comparison of total postoperative prostate-specific antigen levels between the groups showed significantly higher elevation in Group I (postoperative day 1: P=0.013; day 5: P=0.05).

CONCLUSIONS

Coronary revascularization can cause a statistically significant rise in serum total prostate-specific antigen levels. This rise is more marked in patients undergoing conventional coronary revascularization.

Does ischemia-induced prostate damage during cardiac surgery involving cardiopulmonary bypass cause bladder outlet obstruction?

OBJECTIVE

This study sought to investigate whether ischemia-induced prostate damage during cardiac surgery involving cardiopulmonary bypass causes bladder outlet obstruction.

MATERIALS AND METHODS

The study involved 37 men who underwent elective cardiac surgery involving cardiopulmonary bypass. Prostate-specific antigen (PSA) levels were determined preoperatively (baseline) and on postoperative days 1, 5, and 30. In 4 cases, the PSA level after the operation was unchanged from the preoperative level, so these 4 men were excluded from the study. In the remaining 33 patients, symptoms of bladder outlet obstruction were assessed using the International Prostate Symptom Score. Each subject completed this test preoperatively and 3, 6 and 9 months postoperatively, and the means scores at these time points were compared. The effects of patient age, operative time, CPB time, and aortic clamping time on postoperative increases in PSA levels were investigated.

RESULTS

Thirty-three (89.2%) of the 37 men exhibited increased postoperative PSA levels compared to baseline. The mean PSA level for the 33 cases on day 5 was significantly higher than the baseline mean, but the mean levels on postoperative days 1 and 30 were comparable to baseline. Nine (24.3%) of the 33 men had postoperative PSA levels greater than 4.0 ng/dl (the upper normal limit). There was no significant difference between preoperative and postoperative International Prostate Symptom Scores.

CONCLUSION

The study indicates that men's PSA levels are, indeed, increased after cardiac surgery with cardiopulmonary bypass. However, in 9 months of follow-up, there was no association between this PSA rise and development of BOO, according to International Prostate Symptom Scores.

Validity of PSA, free/total PSA ratio and complexed/total PSA ratio measurements in men with acute urinary retention

The reliability of serum prostate specific antigen (PSA) measurements in men with acute urinary retention is unclear. Total PSA, free and complexed PSA were measured, and the free/total (f/t) PSA and complexed/total (c/t) PSA ratios calculated, prior to catheterisation and at 48 and 72 h post-catheterisation in 39 men with acute retention. Subsequent histology showed 12 patients had prostate cancer and 27 benign prostatic hypertrophy. Serum free and total PSA fell following catheterisation, while complexed PSA rose during the first 48 h then subsequently fell. The f/t PSA and c/t PSA ratios provided the best discrimination at 48-72 h with 100% sensitivity and 75-82% specificity.Prostate Cancer and Prostatic Diseases (2001) 4, 167-172.

Elevation of prostate-specific markers after cardiopulmonary resuscitation

BACKGROUND-Prostate-specific antigen (PSA), acid phosphatase (AP), and prostatic acid phosphatase (PAP) are serum markers for adenocarcinoma of the prostate gland. Previous studies indicated that prostatic ischemia may also produce elevations of PSA. Cardiopulmonary resuscitation (CPR) is frequently associated with profound tissue hypoperfusion. The present study investigated whether PSA, AP, and PAP are influenced by prolonged CPR. METHODS AND RESULTS-PSA, AP, and PAP were assessed immediately, 12 hours, 24 hours, 2 days, 3 days, 5 days, and 7 days after prolonged CPR (>5 minutes) in 14 male and 5 female patients. No changes were noted in women. In men, serum levels increased significantly after CPR and gradually decreased to near baseline values after 7 days. PSA, AP, and PAP values above the normal range were observed in 63%, 71%, and 64% of all patients, respectively. Compared with survivors, nonsurvivors exhibited higher peak serum levels of PSA (98.6+/-14.3 versus 1.1+/-2.2 mcg/L; P<0.03), AP (57.0+/-71 versus 8.6+/-8.8 U/L; P<0.05), and PAP (47.0+/-62 versus 5.7+/-8.0 U/L; P=NS). Patients with poor neurological outcome exhibited higher peak serum levels of PSA (86.4+/-135.5 versus 12.0+/-23.8 mcg/L; P<0.05), AP (50.9+/-68.1 versus 8.7+/-9.6 U/L; P=NS), and PAP (41.6+/-59.5 versus 5.8+/-8.8 U/L; P=NS) than patients with good neurological outcome. CONCLUSIONS-Prolonged CPR is frequently associated with increases of PSA, AP, and PAP serum levels. Therefore, PSA cannot be used for diagnosis of adenocarcinoma of the prostate during the first weeks after CPR. Further evaluation of these parameters as additional prognostic markers after CPR is warranted.

Evaluation of the effect of spinal cord injury on serum PSA levels

OBJECTIVES

Prostatic structure and secretory activity are thought to be influenced by autonomic innervation of the prostate. Prostatic denervation is especially likely in patients with spinal cord injury (SCI) at the level of the cauda equina or the conus medullaris, where the peripheral nerve supply to the prostate may be specifically damaged. This may result in changes in serum prostate-specific antigen (PSA) levels, either directly or indirectly. Therefore, we measured serum PSA levels and also studied the influence of factors such as age, catheterization, duration of SCI, urinary tract infection, and history of cystitis on serum PSA values in men with SCI.

METHODS

Serum PSA levels were determined in 79 men with SCI (age older than 40 years) using banked sera by the Abbott MEIA PSA assay. Variables such as age, catheterization, duration of SCI, urine culture results, and history of cystitis were obtained from a review of patient records. Comparisons were made with a randomly selected, non-SCI control population of 501 men, 40 to 89 years old, who underwent serum PSA determination at our institution. Statistical comparisons were performed using the Mann-Whitney U test (nonparametric), since the populations were not normally distributed. Multivariate logistic regression analysis was used to assess the correlation between the various factors and the serum PSA levels in men with SCI.

RESULTS

No statistically significant differences were found in the median serum PSA values between the SCI group and the non-SCI control population. The age-specific PSA values obtained in the SCI group were also comparable to those reported for the general population at large. Age (P <0.03) and the presence of a catheter (P <0.0002) were the only two factors that were correlated with higher serum PSA values in the SCI group by regression analysis.

CONCLUSIONS

Men with SCI tended to have serum PSA value distributions that were similar to those of the general population. However, those in the SCI group who had indwelling catheters were more likely to have higher PSA values at baseline, as were older men with SCI.

Prostate specific antigen: a decade of discovery--what we have learned and where we are going

PURPOSE

Many advances have occurred during the last decade in the clinical use of prostate specific antigen (PSA) for detecting, staging and monitoring prostate cancer. We review the clinical usefulness and limitations of serum PSA as a tumor marker of prostate cancer.

MATERIALS AND METHODS

The English language literature was reviewed with respect to the major contributions and limitations of PSA in present clinical practice.

RESULTS

Although controversial, age specific PSA reference ranges can improve the sensitivity for prostate cancer detection in young men and the specificity in older men. Percent free PSA improves the specificity for prostate cancer detection in men with PSA values between 4 and 10 ng./ml., and a PSA density of greater than 0.15 may better distinguish benign prostatic hyperplasia from prostate cancer. PSA velocity can improve the ability to detect prostate cancer when 3 serial PSA values are measured during a 2-year period. For prostate cancer staging PSA is most useful combined with clinical stage and Gleason score in multivariate analysis. Percent free PSA may prove useful for staging prostate cancer but further clinical trials are needed to determine its clinical usefulness. PSA is the most clinically useful means to monitor disease recurrence after treatment of prostate cancer. With ultrasensitive PSA assays it is now possible to increase the lead time for detection of disease recurrence by several months.

CONCLUSIONS

During the last decade much of the focus has been on improving the ability of this tumor marker to detect prostate cancer. PSA remains the best and most widely used tumor marker in urology today.

Ischemic damage to the prostate during cardiac surgery: a clinical model

BACKGROUND

To determine if altered tissue perfusion during cardiac surgery results in ischemic tissue damage to the prostate, as suggested by a rise in prostatic-specific antigen (PSA).

METHODS

Twenty-nine male patients undergoing elective coronary artery bypass grafting were studied. Ten male patients undergoing elective gastrointestinal surgery served as controls. PSA levels were determined preoperatively and six hourly intervals postoperatively for 48 hr. All patients underwent urethral catheterization at induction of anesthesia.

RESULTS

All patients (100%) who had undergone cardiac bypass surgery showed rises in serum PSA during 48 hr of postoperative follow-up. At the 6-hr postoperative interval, the mean PSA was significantly different from the mean baseline value (paired two tailed Student's t test, P < 0.001) in 27 of the 29 (93%) patients. In contrast, the PSA values in the 10 gastroenterological controls did not change at 6 hr (P > 0.2) or during the next 48 hr. One patient in the cardiac group showed a very marked elevation in serum PSA of greater than 50 times normal preoperative levels.

CONCLUSIONS

Statistically significant rises in PSA levels are seen following coronary bypass surgery. This rise may be caused by ischemic nontrauma related damage to the prostate and suggests a possible pathophysiological mechanism for the clinically episodic symptoms of prostatism seen in elderly men.

The effect of prostatitis, urinary retention, ejaculation, and ambulation on the serum prostate-specific antigen concentration

PSA remains an immensely valuable tool in the diagnosis of prostate adenocarcinoma. Factors such as prostatitis, urinary retention, ejaculation, and inpatient versus outpatient measurement, however, may have a profound effect on the serum PSA concentration. Furthermore, prostate biopsy and TURP result in an increase in the serum PSA value that resolves in 4 to 6 weeks. It is imperative that these factors be taken into account to interpret serum PSA values, to optimize the diagnostic utility of the PSA test.

Constitutive expression of high levels of prostate-specific antigen in the absence of prostate carcinoma

OBJECTIVES

To identify distinguishing serologic features in patients with stable marked elevation in prostate-specific antigen (PSA) and multiple negative biopsies.

METHODS

The study population consisted of 7 patients with a stable PSA level of greater than 20 ng/mL (average 27.0), followed for at least 34 months (average 56), and with two or more negative prostatic biopsies including transition zone biopsies. The PSA density (PSAD), rate of change in PSA, reverse transcriptase/polymerase chain reaction (RT/PCR), and free/total PSA were obtained.

RESULTS

Rate of change in PSA level was stable (0.18 +/- 1.2 ng/mL/yr), suggesting that there was no occult cancer; PSAD was high (0.34 +/- 0.5 ng/mL/cc), indicating that prostate size was not the sole cause of the elevation. The RT/PCR was negative in 6 of 7 patients, further decreasing the likelihood of an occult malignancy. Free versus total PSA was not consistent, averaging 16.8%, but with a range of 6% to 34%.

CONCLUSIONS

Novel PSA tests were not found to be useful in this cohort of patients with multiple negative biopsies and PSA elevations greater than 20 ng/mL. Additional studies with larger sample size are required to confirm this finding.

Effect of elective prolonged urethral catheterization on serum prostate-specific antigen concentration

OBJECTIVES

To determine the effect of an indwelling catheter on prostate-specific antigen (PSA) levels. PSA is an organ (prostate)-specific marker, and its level can be elevated in various pathologies as well as following urologic manipulations. An elevated marker may indicate the presence of prostate cancer. In the presence of an indwelling catheter, our inability to decide whether an elevated PSA value represents genuine pathology or is related to the catheter itself is often of great clinical importance.

METHODS

A prospective study was conducted on 21 men with an indwelling catheter inserted electively for major nonurologic abdominal surgery to determine its influence on PSA concentration. Sera were collected before catheter insertion, 2 hours after, and then every day (average, 16 days). Catheters were left in place for an average of 5.5 days.

RESULTS

Follow-up data compared to baseline and to the previous day's PSA concentrations revealed no significant change in any of the subjects. In 2 men with elevated preinsertion PSA levels (more than 10.0 ng/mL), the change over time did not differ in magnitude from changes in the other 19 men with normal pretreatment values.

CONCLUSIONS

Inserting a urethral catheter and maintaining it for several days does not result in any clinically or statistically significant change in PSA levels. PSA values obtained in patients with an indwelling catheter are reliable and independent of its presence. An elevated level mandates prompt evaluation to exclude prostate cancer.

A guide to the interpretation of serum prostate specific antigen levels

OBJECTIVE

To review the factors that affect the concentration of prostate specific antigen (PSA) in the serum.

RESULTS

The discussion includes the structure of PSA; its distribution and metabolism; various analytical aspects of PSA measurements; the effects of clinical manipulations on PSA, including digital rectal examination, transrectal ultrasound, cystoscopy, biopsy and transurethral resection of the prostate; factors affecting PSA levels in health, in benign disease, and in prostate cancer; the effect of various treatments on PSA; and the issue of reference ranges.

CONCLUSION

Laboratory staff and physicians must take many factors into consideration when interpreting PSA results.