Prostate cancer screening: Role of digital rectal examination and prostate-specific antigen

Background: This study was designed to determine the efficacy of digital rectal examination (DRE) and serum prostate-specific antigen (PSA) for early detection of prostate cancer in men ≥50 years of age. Methods: A prospective single-center clinical trial was conducted to screen 644 asymptomatic men, who were elicited by newspaper and radio advertisements, with DRE and PSA. Quadrant biopsy examinations of the prostate were performed if PSA >4 ng/ml or if DRE was suspicious. Results: Thirty-seven percent of the men (n=241) had an abnormality of DRE or elevated PSA. Of the 163 patients who underwent transrectal ultrasound and quadrant biopsies of the prostate, 77% had normal biopsies, 14 (8%) had prostatic intraepithelial neoplasia, and 24 (15%) had carcinoma of the prostate. PSAs ranged from 0.3 to 65.5 ng/ml, with a mean of 2.35 and a median of 1.6. Ninety-five patients had a PSA >4 ng/ml, of whom 17 had a PSA >10 ng/ml. Sensitivity of PSA was 75% and specificity 87%; for DRE the sensitivity was 75% and the specificity 69%. Clinical stage of patients who underwent radical prostatectomy was B1 in 15 and B2 in five. Fifteen of 20 patients (75%) had organ-confined disease; the other five had specimen-confined disease. No patient was found to have nodal involvement. Conclusion: The combination of PSA and DRE seems to improve the stage of diagnosis of patients with prostate cancer. Larger, randomized studies will be necessary to evaluate the effect of screening on overall survival. The results of this study were presented at the 46th annual cancer symposium of the Society of Surgical Oncology, Los Angeles, California, March 18–20, 1993.     

Prostate cancer: correlation of digital rectal examination, transrectal ultrasound and prostate specific antigen levels with tumor volumes in radical prostatectomy specimens.

Volume and distribution of prostatic carcinoma were measured in 30 radical prostatectomy specimens. Obtaining these data was facilitated by the use of whole tissue mounts. Similar measurements were obtained from preoperative transrectal ultrasound studies. With this information the ability of digital rectal examination and transrectal ultrasound to predict tumor burden was analyzed. It was concluded that both of these examinations are poor predictors of tumor volume, distribution and pathological stage. Preoperative prostate specific antigen levels were correlated with the pathological data. It appeared that prostate specific antigen levels of greater than 10 presage [corrected] tumor volumes of greater than 3 cc, and that levels of more than 50 are suggestive of stages C and D disease.     

Prostate cancer and transrectal ultrasound

We describe the ultrasonographic changes prostate cancer can produce, and analyze the usefulness of ultrasonography in the study of this disease. Transrectal ultrasound does not have enough sensitivity and specificity for the diagnosis, metastasic study, and diagnosis of recurrences after radical prostatectomy. Nevertheless the ultrasound study of the morphology of the prostatic apex may be useful for the planning and performance of the apex dissection during radical prostatectomy.     

Screening for prostate cancer. Comparison of transrectal ultrasound, prostate specific antigen and rectal examination.

In seeking to define the relative value of transrectal ultrasound (TRUS), prostate specific antigen (PSA) and digital rectal examination (DRE) in the diagnosis of prostatic cancer, 863 patients were studied and the findings compared. DRE detected malignancy in 0.3% of the population of asymptomatic "normal" men undergoing routine health screening, and in 1.6% of patients who consulted their General Practitioner for one reason or another. In patients who attended our out-patient department with a variety of urological symptoms (not necessarily prostatic), TRUS suggested malignancy in 2% of those glands which were pronounced normal on DRE. Significantly elevated PSA detected malignancy in 0.3% of the patients undergoing routine health screening. (Although this figure equals the pick-up rate by DRE in this group, they were not necessarily the same patients). When these 3 investigations are summated, the pick-up rate is twice as high as when a single parameter is used.     

Prostate cancer detection with digital rectal examination, prostate-specific antigen, transrectal ultrasonography and biopsy in clinical urological practice

OBJECTIVE: To evaluate the utility of digital rectal examination (DRE), prostate specific antigen (PSA) and transrectal ultrasonography and biopsy (TRUSB) in detecting prostate cancer in one teaching-hospital urological practice. PATIENTS AND METHODS: In all, 2800 consecutive patients had TRUSB as outpatients by one urologist, the indications for which were a raised or rising PSA level or an abnormal DRE. In addition, the indications for repeat TRUSB included previous abnormal histology, e.g. suspicious areas or atypia or high-grade prostatic intraepithelial neoplasia. All data were collected prospectively. RESULTS: Of 2800 TRUSB, 223 were known cases of prostate cancer (previously diagnosed from transurethral prostatectomy chips or after radical prostatectomy) and were excluded from the analysis. There were 2194 initial and 383 repeat TRUSB; of the former patients, 1129 were found to have prostate cancer, giving a cancer-detection rate of 52%. The positive predictive values (PPVs) for patients with a normal DRE and PSA of < 4, 4-10 and > 10 ng/mL were 9%, 31% and 48%, respectively; the corresponding PPVs for patients with an abnormal DRE and the same PSA levels were 27%, 67% and 85%, respectively. Of the 383 repeat TRUSB, the cancer-detection rate was 31% for the first repeat and 28% for the second. CONCLUSIONS: The present values are higher than those reported previously, because these patients were within a clinical urological practice, and the indications for and methods of TRUSB have changed in recent years, such that more lateral areas were biopsied. These values are useful in helping clinicians to counsel patients about the probability of detecting cancer.     

Assessment of screening for prostate cancer using the digital rectal examination

An early detection study for prostate cancer was initiated to determine the effect of routine digital rectal examinations on the stage of prostate cancer at diagnosis. A prostate biopsy was recommended if induration, asymmetry or nodules were detected on the digital examination. During a 6-year period 4,160 examinations were performed on 2,131 men more than 45 years old. A prostate biopsy was performed on 144 men and 36 malignant tumors were detected, of which 68 per cent were clinically localized. Pelvic lymph node metastases were found in 6 per cent of the surgically staged cancer patients and in 10 per cent of the patients who had a high grade tumor. Surgical staging revealed that 50 per cent of the patients with clinical stage B disease were upstaged to stage C or D1 disease. These results suggest that mass screening programs using digital examination may not add sufficient benefit over conventional medical care to warrant the expense. Definitive proof that screening can lower the mortality rate from prostate cancer can be obtained only by a prospective randomized clinical trial.     

Screening for prostate cancer without digital rectal examination and transrectal ultrasound: results after four years in the European Randomized Study of Screening for Prostate Cancer (ERSPC), Rotterdam

BACKGROUND: Omission of DRE/TRUS as biopsy indication results in fewer unnecessary biopsies, but may increase the risk of missing potentially aggressive prostate cancers (PCs). In 1997, the biopsy indication within the ERSPC was changed from a PSA cut-off of 4.0 ng/ml and/or abnormal DRE/TRUS (group-1) to solely a PSA cut-off of 3.0 ng/ml (group-2). We estimated the effect of omitting DRE/TRUS by comparing the results of a re-screening 4 years after initial screening to the original policy. METHODS: We compared rate and characteristics of detected PCs in the second round in men initially screened in group-1 (N=5,957) or group-2 (N=8,044). Additionally, we compared the rate of interval cancers (ICs) after screening with and without DRE/TRUS. RESULTS: There was no significant difference in second round cancer-detection-rates (group-1, 3.0%; group-2, 2.7%), positive-predictive-values (group-1, 23.9%; group-2, 26.3%), and number of poorly-differentiated tumors (group-1, 2.6%; group-2, 3.8%). Most PCs were clinically confined to the prostate. Eleven ICs were detected in each group (0.18 and 0.14%). CONCLUSIONS: Omitting DRE/TRUS did not result in an increased IC- or PC-detection. However, considering the natural history of PC, the 4-year follow-up may be too short to draw a definitive conclusion.     

Prostate specific antigen testing and digital rectal examination before and during a randomized trial of screening for prostate cancer: European randomized study of screening for prostate cancer, Rotterdam

PURPOSE: Worldwide 2 large-scale randomized screening trials for prostate cancer have been initiated. Determining prostate specific antigen (PSA) involves a simple test that may influence the outcome of these trials if frequently done in the control arm or before study enrollment. We quantified PSA and digital rectal examination before and during the screening trial in Rotterdam, The Netherlands and in the general population. MATERIALS AND METHODS: Trial participants were administered study intake questionnaires on tests done before study participation. Data on PSA from the regional general practice laboratory were correlated with participant data. Various sources were used to quantify PSA tests and digital rectal examinations in the general population. RESULTS: Of men 55 to 74 years old 45% underwent digital rectal examination at 1 time and 13% reported that PSA was tested before trial participation. Each rate increased with age. No statistically significant effect of former PSA testing or digital rectal examination on the cancer detection rate was identified. The rate of PSA determination after initial screening and/or randomization in the control arm was 2-fold that in the screening arm (76 versus 33/1,000 person-years). PSA determination initially decreased in the screening arm but increased rapidly after some time. The number of PSA determinations in the general population was estimated to be 45/1,000 person-years at ages 55 to 69 years. CONCLUSIONS: PSA testing was moderate in the control arm but if different men undergo this test each year, the contamination rate may become rather high. In the final analysis of mortality PSA testing should be considered.     

Elevated prostate-specific antigen, abnormal prostate evaluation on digital rectal examination, and transrectal ultrasound and prostate biopsy

Prostate cancer screening for the early diagnosis of organ-confined, potentially curable prostate cancer has dramatically changed the practice of urology over the past 15 years. The introduction of prostate-specific antigen (PSA) testing, increased medical and public awareness for digital rectal examination (DRE), and transrectal ultrasound-assisted needle biopsy of the prostate (TRUS/PNBX) has been instrumental in these dramatic changes.     

Prostate-specific antigen coordinated with digital rectal examination and transrectal ultrasonography in the detection of prostate cancer

Summary In a aptient population, coordinated use of digital rectal examination and prostate-specific antigen can alert the physician as to the possible existence of prostate cancer. If both are used as first-line studies, abnormality of either can then direct the need for further study by transrectal ultrasonography and, in selected instances, prostatic biopsy. Such sequential use of these tests in a programmed manner results in an increased level of cancer detection as compated with use of the digital rectal examination alone.     

Evaluation of prostatic specific antigen and digital rectal examination as screening tests for prostate cancer

BACKGROUND: The 11,811 first visits and 46,751 annual follow-up visits performed since 1988 were analyzed in order to assess the efficacy of serum prostatic specific antigen (PSA) and digital rectal examination (DRE) for diagnosis of prostate cancer. METHODS: At first visit, screening included DRE and measurement of PSA using 3.0 ng/ml as upper limit of normal, demonstrated as optimal value in the course of the study. Transrectal echography of the prostate (TRUS) was performed only if PSA and/or DRE was abnormal. For elevated PSA, biopsy was performed only if PSA was above the value predicted from prostatic volume measured by TRUS. At follow-up visits, it was decided during the course of the study to use PSA alone. RESULTS: PSA was above 3.0 ng/ml in 16.6% and 15.6% of men at first and follow-up visits, respectively. Prostate cancer was found in 2.9% of men invited for screening at first visit and in only 0.4% of men at follow-up visits for a 7.1-fold decrease at follow-up visits done up to 11 years. PSA alone allowed to find 90.5% and 90. 0% of cancers at first and follow-up visits, respectively, compared to 41.1% and 25.0% by DRE alone. In the presence of normal PSA, 344 and 1,919 DREs are needed to find one prostate cancer at first and follow-up visits, respectively. A significant improvement in stage of the disease is found at follow-up (215 cancers) compared to first visits (337 cancers). Comparison made between men invited for screening and those who were not invited but screened showed no significant difference in terms of incidence and prevalence of prostate cancer as well as diagnosis of cancer as a function of age or as a function of PSA, DRE, and TRUS data. The cost for finding one case of prostate cancer is estimated at Can $2,420 and Can $7, 105 (first and follow-up visits, respectively, when PSA is used as prescreening). CONCLUSIONS: PSA used as prescreening and followed by DRE and TRUS when PSA is abnormal is highly efficient in detecting prostate cancer at a localized (potentially curable) stage since 99% of the cancers diagnosed were at such a localized stage, thus practically eliminating the diagnosis of metastatic and noncurable prostate cancer. The approach used is highly reliable, sensitive, efficient, and acceptable by the general population. The detection of clinically nonsignificant cancer is an exception.     

Preoperative prediction of pathological tumor volume and stage in clinically localized prostate cancer: comparison of digital rectal examination, transrectal ultrasonography and magnetic resonance imaging.

Accurate preoperative staging is important for proper selection of patients for radical retropubic prostatectomy. Preoperative staging by digital rectal examination, transrectal ultrasound, magnetic resonance imaging (MRI), Gleason grade and prostate specific antigen was compared to pathological stage for 25 patients who underwent radical retropubic prostatectomy. The predictive value for tumor confinement was 36% by rectal examination, 37% by ultrasound and 30% by MRI. The predictive value for extracapsular disease was 100% by rectal examination, 83% by ultrasound and 66% by MRI. Preoperative determinations of tumor volume by any modality did not correlate with pathological tumor volume. Digital rectal examination, ultrasound and MRI clinically understage the disease in most patients but they may be reliable to predict extracapsular disease.     

Comparison of the efficacy of digital rectal examination and transrectal ultrasonography in the diagnosis of prostatic cancer

167 patients with a mean age of 64 years underwent digital rectal examination (DRE), transrectal ultrasonography with a 7-MHz transverse and/or longitudinal transducer, followed by prostatic biopsy under ultrasound guidance. 231 biopsies were performed. 74 peripheral hypoechogenic zones were demonstrated. The sensitivity of DRE was 82% and the specificity 91%. The sensitivity and the specificity of ultrasound were respectively 69 and 83%. On 123 patients with normal DRE, 19 hypoechoic zones were detected and 2 patients had a positive biopsy (11%). On 104 patients without hypoechoic zone, 5 biopsies were positive (5%). The use of transrectal ultrasound scanning is able to multiply the number of impalpable cancer by 2, but in only 3 lobes, a hypoechogenic zone associated with a normal rectal examination was confirmed to be a cancer on biopsy. These cases represent 5.5 of the 56 positive biopsies, 4% of the hypoechogenic zones and 1.6% of the investigated patients with normal rectal examination. No impalpable cancer of 5 mm or less was detected by high resolution ultrasonography. DRE is still the most reliable examination for the diagnosis of prostatic cancer. Ultrasonography is a useful complement, particularly by allowing collection of tissue interpretable by the histologist in 100% of cases.     

Accuracy of prostate weight estimation by digital rectal examination versus transrectal ultrasonography

PURPOSE: The ability to estimate prostate weight is useful. Two commonly used methods for estimating prostate weight are digital rectal examination (DRE) and transrectal ultrasonography (TRUS). We evaluated the relative accuracy of these weight estimates by comparing them to prostate weight following radical retropubic prostatectomy (RRP). MATERIALS AND METHODS: Between 1989 and 2001 more than 36,000 community men participated in a large prostate cancer screening study. Of these men 2,238 underwent RRP. In this subset we examined the correlation between documented preoperative DRE and TRUS estimates of prostate weight with actual gland weight. RESULTS: DRE estimates of prostate weight by multiple examiners correlated poorly with RRP specimen weight (r = 0.2743). However, TRUS estimates correlated moderately well (r = 0.6493). TRUS provided more accurate estimates of prostate weight for smaller glands, although it generally underestimated gland weight compared to the weight of the surgical specimen. CONCLUSIONS: In a large, community based prostate cancer screening study prostate weight estimated by DRE was shown to correlate poorly with actual prostate weight. Compared with DRE, TRUS provides a better estimate of prostate weight. In addition, TRUS measurements were more accurate in smaller prostate glands.     

Comparison of digital examination and transrectal ultrasonography for the diagnosis of prostatic cancer

The ability to detect prostatic cancer by transrectal ultrasonography was evaluated in a prospective blind study of 216 men. The sensitivity of transrectal ultrasonography was 86 per cent but the specificity was only 41 per cent. Tumors less than 1 cm. in diameter were most difficult to detect by transrectal ultrasonography. The positive and negative predictive values of transrectal ultrasonography were 36 and 89 per cent, respectively. Abnormal scans that strongly suggested carcinoma were present in 10 per cent of the men who had a normal digital examination but no biopsy was performed. Transrectal ultrasound is a sensitive method to detect all but small prostatic tumors and it can detect tumors that are not evident by digital examination. To date, however, transrectal ultrasonography may be difficult to use for routine screening in the United States because of the low positive predictive value. Nevertheless, further investigation of this technique is warranted to define its role in improving the diagnosis of prostatic cancer.     

Prostate cancer detection in a clinical urological practice by ultrasonography, digital rectal examination and prostate specific antigen.

The prostate cancer detection rate from screening by digital rectal examination and tactilely guided prostate biopsy is approximately 1.7%. Among 1,807 men a detection rate of 14.6% was achieved in a clinical urological practice by physician-conducted prostate ultrasonography, digital rectal examination and determination of serum prostate specific antigen. Results are presented in 5-year increments as well as for the group as a whole. The possible benefit to be derived from an improved detection rate is undetermined. Recommendations are made regarding the clinical use of these diagnostic modalities.