Screening for carcinoma of the prostate: a GP based study

Comparing the Performance of Digital Rectal Examination and Prostate-specific Antigen as a Screening Test for Prostate Cancer: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVE

Although digital rectal examination (DRE) is recommended in combination with prostate-specific antigen (PSA) for detection of prostate cancer (PCa), there are limited data to support its use as a screening/early detection test. Our objective was to assess the diagnostic value of DRE in screening for early detection of PCa.

METHODS

In August 2023, we queried the PubMed, Scopus, and Web of Science databases to identify prospective studies simultaneously investigating the diagnostic performance of DRE and PSA for PCa screening. The primary endpoints were the positive predictive value (PPV) and cancer detection rate (CDR) of DRE. Secondary endpoints included the PPV and CDR of both PSA alone and in combination with DRE. We conducted meta-regression analysis to compare the CDR and PPV of different screening strategies. This meta-analysis is registered on PROSPERO (CRD42023446940).

KEY FINDINGS AND LIMITATIONS

We identified eight studies involving 85 738 participants, of which three were randomized controlled trials and five were prospective diagnostic studies, that reported the PPV and CDR of both DRE and PSA for the same cohort. Our analysis revealed a pooled PPV of 0.21 (95% confidence interval [CI] 0.13-0.33) for DRE, which is similar to the PPV of PSA (0.22, 95% CI 0.15-0.30; p = 0.9), with no benefit from combining DRE and PSA (PPV 0.19, 95% CI 0.13-0.26; p = 0.5). However, the CDR of DRE (0.01, 95% CI: 0.01-0.02) was significantly lower than that of PSA (0.03, 95% CI 0.02-0.03; p < 0.05) and the combination of DRE and PSA (0.03, 95% CI 0.02-0.04; p < 0.05). The screening strategy combining DRE and PSA was not different to that of PSA alone in terms of CDR (p = 0.5) and PPV (p = 0.5).

CONCLUSIONS AND CLINICAL IMPLICATIONS

Our comprehensive review and meta-analysis indicates that both as an independent test and as a supplementary measure to PSA for PCa detection, DRE exhibits a notably low diagnostic value. The collective findings from the included studies suggest that, in the absence of clinical symptoms and signs, DRE could be potentially omitted from PCa screening and early detection strategies.

PATIENT SUMMARY

Our review shows that the screening performance of digital rectal examination for detection of prostate cancer is not particularly impressive, suggesting that it might not be necessary to conduct this examination routinely.

A discussion on controversies and ethical dilemmas in prostate cancer screening

Prostate cancer (PCa) is one of the the most common cancers in men. A blood test called prostate-specific antigen (PSA) has a potential to pick up this cancer very early and is used for screening of this disease. However, screening for prostate cancer is a matter of debate. Level 1 evidence from randomised controlled trials suggests a reduction in cancer-specific mortality from PCa screening. However, there could be an associated impact on quality of life due to a high proportion of overdiagnosis and overtreatment as part of the screening. The US Preventive Services Task Force (USPSTF) in 2012 recommended that PSA-based PCa screening should not to be offered at any age. However, considering the current evidence, USPSTF recently revised its recommendation to offer the PSA test to men aged 55-69 years with shared decision-making, in line with earlier guidelines from the American Cancer Society and the American Urological Association. A shared decision making is necessary since the PSA test could potentially harm an individual. However, the literature suggests that clinicians often neglect a discussion on this issue before ordering the test. This narrative discusses the main controversies regarding PCa screening including the PSA threshold for biopsy, the concept of overdiagnosis and overtreatment, the practical difficulties of active surveillance, the current level 1 evidence on the mortality benefit of screening, and the associated pitfalls. It offers a detailed discussion on the ethics involved in the PSA test and highlights the barriers to shared decision-making and possible solutions.

Digital Rectal Examination for Prostate Cancer Screening in Primary Care: A Systematic Review and Meta-Analysis

PURPOSE

Although the digital rectal examination (DRE) is commonly performed to screen for prostate cancer, there is limited data to support its use in primary care. This review and meta-analysis aims to evaluate the diagnostic accuracy of DRE in screening for prostate cancer in primary care settings.

METHODS

We searched MEDLINE, Embase, DARE (Database of Abstracts of Reviews of Effects), Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and CINAHL (Cumulative Index to Nursing and Allied Health Literature) from their inception to June 2016. Six reviewers, in pairs, independently screened citations for eligibility and extracted data. Pooled estimates were calculated for sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of DRE in primary care settings using an inverse-variance meta-analysis. We used QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies 2) and GRADE (Grades of Recommendation Assessment, Development, and Evaluation) guidelines to assess study risk of bias and quality.

RESULTS

Our search yielded 8,217 studies, of which 7 studies with 9,241 patients were included after the screening process. All patients analyzed underwent both DRE and biopsy. Pooled sensitivity of DRE performed by primary care clinicians was 0.51 (95% CI, 0.36-0.67; I² = 98.4%) and pooled specificity was 0.59 (95% CI, 0.41-0.76; I² = 99.4%). Pooled PPV was 0.41 (95% CI, 0.31-0.52; I² = 97.2%), and pooled NPV was 0.64 (95% CI, 0.58-0.70; I² = 95.0%). The quality of evidence as assessed with GRADE was very low.

CONCLUSION

Given the considerable lack of evidence supporting its efficacy, we recommend against routine performance of DRE to screen for prostate cancer in the primary care setting.

Acceptability of digital anal cancer screening examinations in HIV-positive homosexual men

OBJECTIVES

Anal cancer is more common in HIV-positive homosexual men than in HIV-negative homosexual men and the general population. Earlier diagnosis leads to improved prognosis. We aimed to determine if regular anal inspection and digital examination of asymptomatic homosexual men attending for routine HIV care were acceptable and to record the rate of referral for diagnosis of potentially malignant anal lesions.

METHODS

We offered anal examinations to consecutive homosexual men with HIV infection aged ≥ 35 years during their routine HIV clinic visits, aiming to complete three examinations over a 12-month period. Acceptability questionnaires were completed at baseline and after each examination and doctors recorded examination findings and all resulting interventions. Hospital referral outcomes were collected and interventions were costed using the Australian Medical Benefits Schedule.

RESULTS

Of 142 men who were offered enrolment in the study, 102 [72%; 95% confidence interval (CI) 64-79%] participated. Following the initial anal examinations, four men were referred to surgeons. Cancer was excluded in three men (3%; 95% CI 1-8%) and one was diagnosed with anal squamous cell carcinoma (SCC). Three men had anoscopy performed at the time and two were referred for colonoscopy. Ninety-eight per cent (95% CI 93-100%) of respondents said that they would probably have the examination next time. The intervention was estimated to cost approximately Australian $16 per examination.

CONCLUSIONS

Regular anal digital examinations are an acceptable and inexpensive addition to the routine care of homosexual men with HIV infection.

Is Routine Digital Rectal Examination Required for the Followup of Prostate Cancer?

PURPOSE

With more men being diagnosed and radically treated for prostate cancer there is an increasing number of patients requiring followup. A proportion of radically treated patients have recurrence and require early salvage treatment. Traditionally followup involved physical examination, urinalysis, imaging and biopsy. Since the development of the prostate specific antigen assay, followup has largely consisted of digital rectal examination and prostate specific antigen determination. Although digital rectal examination is routinely used, its efficacy for detecting recurrent cancer in the absence of biochemical evidence of disease progression was questioned in recent studies.

MATERIALS AND METHODS

We performed a literature search using the key words digital rectal examination, per rectal examination, radical prostatectomy and radical radiotherapy, and cross-referenced all results.

RESULTS

The literature that supports digital rectal examination as part of patient followup after radical prostatectomy is based on case studies and it is less applicable with more sensitive prostate specific antigen assays. In almost 5,000 patients after prostatectomy a prostate specific antigen increase reliably preceded disease recurrence, making digital rectal examination superfluous to requirements. No published literature supports repeat digital rectal examination after radical radiotherapy.

CONCLUSIONS

Prostate specific antigen allows the early detection of disease recurrence. Although digital rectal examination is widely used to follow patients, contemporary studies consistently show that disease progression does not occur in the absence of increasing prostate specific antigen. This suggests that remote followup of patients with prostate specific antigen alone is a safe practice, although caution should be exercised in those with higher grade tumors, which may not produce significant amounts of prostate specific antigen.

Adjusting for treatment refusal in rationing decisions

Assessments of cost effectiveness are increasingly used to get the most value from limited health resources. Could adjusting for people who wouldn't want the treatment improve the process?

Semen characteristics: Advancement in andrological assessment

Progress in diagnosis of infertility, has been dramatically increased during the past decades with changes occurring in virtually all aspects of infertility research, thus providing innovative diagnostic testing and sophisticated instrumentation for improved management and treatment of infertility. There are about 50% of infertile couples who are suffering because of male infertility. Semen examination is a basic investigation for these infertile couples. It not only reveals the quantity and quality of sperm but also the quality of the seminal plasma, which is essential for normal sperm function. In this review, the recent advancement in investigation procedures has been analyzed which are very important in clinical practice to (a) evaluate the sperm fertilizing ability (Acrosin, aniline blue, HOS), (b) characterization of male accessory sex glands secretions (Fructose, alpha-glucosidase, PSA) and (c) the management of azoospermic patients. It is believed that use of such diagnostic procedures will facilitate wide selection of patients for whom an effective therapy might be then possible.

PSA testing in general practice

A questionnaire was sent to 400 general practitioners (GPs), concerning prostate-specific antigen (PSA) screening. Regarding the indications for PSA testing, 80% of GPs test men with urinary tract symptoms, 65% test men with a positive family history, 62% test on patient request, and 21% test men with unrelated symptoms. When PSA is measured, 91% of GPs inform their patient, and 71% discuss the significance of an abnormal result. The mean age range for PSA testing was from 50 years, without an upper age limit. The mode PSA threshold for referral was 6.6 ng/ml. De facto PSA screening appears to be widely practised.

Prevalence of undiagnosed prostate cancer in men with erectile dysfunction

OBJECTIVE

To explore the prevalence of prostate cancer in men presenting with erectile dysfunction (ED).

PATIENTS AND METHODS

In a prospective study, 127 men with ED of at least 6 months duration underwent screening for prostate cancer using prostate specific antigen (PSA) and a digital rectal examination (DRE). Men with a high PSA level (> 4 ng/mL) had sextant biopsies taken under sedoanalgesia. The serum testosterone level was measured in all the men.

RESULTS

Twenty-six men were aged < 50 years and all had a normal PSA level; of 101 men aged > 50 years, 20 had an abnormal PSA. The detection rate for prostate cancer using PSA and DRE was 5%, which was not significantly higher than in the general population. All the detected cancers were clinically significant (> T2a, Gleason grade > 4). Two of the five men diagnosed with prostate cancer were Afro-Caribbean. Of the 127 men, 31% had a low serum testosterone level, but there was no association between testosterone and PSA levels.

CONCLUSIONS

Prostate cancer is no more common in men with ED than in the normal male population. Therefore, routine screening for prostate cancer in men with ED is not indicated.

Indicators of pathologic stage of prostate cancer and their use in clinical practice

Pathologic stage is the most reliable means of predicting the likelihood of curable prostate cancer at the time of definitive treatment. Its prediction is of the greatest importance to individuals with clinically localized disease, principally because of the therapeutic and prognostic implications. Multivariate models integrating variables that can be derived from clinical and pathologic assessment have been shown to be reliable and useful in urologic practice. Among these variables, the combination of clinical stage, serum PSA, and biopsy Gleason score provides reliable assessment of the risk for extraprostatic disease that can be used readily for counseling individual patients. Other biopsy-derived parameters may contribute additional information, but their value in multivariate analysis has not been validated in a multi-institutional setting. The development of new prognostic markers is a priority objective in current research to distinguish patients in whom cancer cannot be controlled by surgical treatment. For patients undergoing radical prostatectomy, definitive pathologic stage certainly will remain an important prognostic factor; therefore, clinical practice will continue to be determined by its accurate prediction.

Patient acceptance of endovaginal ultrasound

OBJECTIVE

To assess women's experiences and attitudes regarding endovaginal ultrasound.

METHODS

Women attending the obstetrics and gynecology clinics at the University of Florida were asked to complete an anonymous questionnaire.

RESULTS

Of respondents who had had a prior endovaginal ultrasound examination, 26% reported that 'it hurt a lot' and 50% reported that 'it hurt a little'. In contrast, only 23% of patients had experienced any pain with a prior abdominal ultrasound (P < 0.001). Multivariate analysis showed that discomfort with a prior vaginal ultrasound was related to patient age category, with less discomfort being experienced with increasing ages (P = 0.001). A history of unwanted sex, sexual or physical abuse, or dyspareunia was not associated with more painful examinations. Most patients were willing to undergo a future vaginal ultrasound investigation if it were recommended by their doctor. Multivariate analysis showed that more willingness was associated with older age category (P = 0.004), a history of dyspareunia (P = 0.03) and bleeding in a current pregnancy (P = 0.005). Of the patients (less than half) who had a preference, most preferred a female sonographer for endovaginal sonography (P < 0.001) and most preferred that a doctor, rather than a nurse or technician, perform the examination (P < 0.001).

CONCLUSIONS

The majority of women who had experienced a vaginal ultrasound examination found it somewhat uncomfortable, but almost all women who returned the questionnaire expressed a willingness to undergo endovaginal ultrasound if it were recommended.

Prostate cancer in the elderly

The incidence of prostate cancer is age related and increased longevity increases the number of elderly men with the disease. Management of prostate cancer in the elderly requires a different approach. Screening and aggressive case finding to seek out early confined disease are contraindicated in those with a life expectation below 10 years. Early confined disease in the elderly is usually managed expectantly. Hormone treatment is more appropriate for locally advanced disease, and is a valuable non-surgical treatment for bladder outflow obstruction due to prostate cancer. A significant proportion of elderly men with prostate cancer still die from other diseases. Hormone refractory disease in the elderly should be managed by palliation of symptoms rather than toxic second-line therapies. The aim always is diagnosis where appropriate, treatment which will be of benefit, and quality rather than length of life.

Early detection of prostate cancer in men with prostatism and intermediate prostate-specific antigen levels

OBJECTIVES

To determine the prevalence of prostate cancer and the diagnostic ability of prostate-specific antigen density (PSAD) in men with lower urinary tract symptoms and intermediate prostate-specific antigen (PSA) levels of 4 to 10 ng/mL (Hybritech assay) and to assess the clinical significance of prostate cancers in men who subsequently underwent radical prostatectomy.

METHODS

Six systematic transrectal ultrasonography (TRUS)-guided biopsies were performed in 153 symptomatic men (mean age, 66 years) with PSA levels between 4 and 10 ng/mL, irrespective of digital rectal examination (DRE) findings. Prostate volume was also determined by TRUS and PSAD was calculated (serum PSA divided by volume of entire prostate). The rate of positive biopsies was compared with PSAD (more than 0.2 versus less than 0.2), DRE (positive versus negative), and patient's age (more than 70 years versus 61 to 70 versus 60 or less). Eligible patients with cancer underwent radical prostatectomy, and specimens were analyzed with regard to clinical significance of tumors.

RESULTS

The overall cancer detection rate was 29.4%. PSAD and DRE, but not age, were both statistically significant in differentiating negative from positive biopsies. Independent of DRE findings, mean PSAD was significantly lower in biopsy-negative cases (0.29 +/- 0.17 and 0.25 +/- 0.16) than it was in positive cases (0.34 +/- 0.17 and 0.35 +/- 0.15). Half of the patients who underwent radical prostatectomy had pathologically nonorgan-confined disease (more than pT3), 34% had positive margins, and 47% had a Gleason score of 8 to 10. PSAD, DRE, and age could not predict outcome, probably owing to the small number of patients. However, the number of positive biopsies (1 or 2 versus 3 to 6) was able to predict pathologic stage.

CONCLUSIONS

In men with lower urinary tract symptoms and intermediate PSA levels of 4 to 10 ng/mL, PSAD may be useful in the selection of patients for prostate biopsy. Carcinomas found using these criteria are of clinical importance.