Age-specific PSA reference ranges in a group of non-urologic patients

A Primary Care Provider's Guide to Preventive Health After Spinal Cord Injury

Objective: Provide guidance for preventive health and health maintenance after spinal cord injury (SCI) for primary care providers (PCPs). Main message: Individuals with SCI may not receive the same preventive health care as the general population. Additionally, SCI-related secondary conditions may put their health at risk. SCI is considered a complex condition associated with many barriers to receiving quality primary care. Attention to routine preventive care and the unique health considerations of persons with SCI can improve health and quality of life and may prevent unnecessary health care utilization. Conclusion: PCPs are experts in preventive care and continuity of care, however individuals with SCI may not receive the same preventive care due to numerous barriers. This article serves as a quick reference for PCPs.

Age-specific reference ranges for prostate-specific antigen among healthy Syrian men

Prostate-specific antigen (PSA) has become the most useful serum tumor marker in adjunct to digital rectal examination (DRE) for the management of prostate cancer (PC). The currently cited reference range of normal PSA levels (between 0 and 4.0 ng/mL) is deficient in terms of both sensitivity and specificity. Age-adjusted PSA have been proposed as an alternative to serum PSA. The primary objective of the present study is to determine the age-specific PSA and the percentage of free PSA (%FPSA) in healthy Syrian men. A total of 3,000 healthy Syrian men over 40 years old participated in this study. All men were asked to have total serum (TPSA) and free PSA (FPSA) tested, a DRE, and, when recommended, a prostate biopsy. Serum TPSA levels correlated with age (r=0.30, p<0.001). The 95th percentile TPSA values ranged from 1.7 ng/mL in the age group 40–49 years to 5.8 ng/mL in the group 70–80 years. The general pattern for medians and the percentile values for FPSA across age groups were similar to those seen for TPSA concentrations (r=0.37, p<0.001). However, the %FPSA was fairly constant across age groups except for the higher ratios in the youngest age group. These findings confirm that the serum TPSA and FPSA levels correlate with age. Interestingly, however, Syrian men have lower PSA values compared with other races. Racial differences of PSA concentrations were observed. Our results may help increasing the sensitivity and specificity of PSA measurements in the diagnosis of prostate cancer in Syria and probably in the surrounding regions.

Very low PSA concentrations and deletions of the KLK3 gene

BACKGROUND

Prostate-specific antigen (PSA), a widely used biomarker for prostate cancer (PCa), is encoded by a kallikrein gene (KLK3, kallikrein-related peptidase 3). Serum PSA concentrations vary in the population, with PCa patients generally showing higher PSA concentrations than control individuals, although a small proportion of individuals in the population display very low PSA concentrations. We hypothesized that very low PSA concentrations might reflect gene-inactivating mutations in KLK3 that lead to abnormally reduced gene expression.

METHODS

We have sequenced all KLK3 exons and the promoter and searched for gross deletions or duplications in KLK3 in the 30 individuals with the lowest observed PSA concentrations in a sample of approximately 85 000 men from the Prostate Testing for Cancer and Treatment (ProtecT) study. The ProtecT study examines a community-based population of men from across the UK with little prior PSA testing.

RESULTS

We observed no stop codons or frameshift mutations, but we did find 30 single-base genetic variants, including 3 variants not described previously. These variants included missense variants that could be functionally inactivating and splicing variants. At this stage, however, we cannot confidently conclude whether these variants markedly lower PSA concentration or activity. More importantly, we identified 3 individuals with different large heterozygous deletions that encompass all KLK3 exons. The absence of a functional copy of KLK3 in these individuals is consistent with their reduced serum PSA concentrations.

CONCLUSIONS

The clinical interpretation of the PSA test for individuals with KLK3 gene inactivation could lead to false-negative PSA findings used for screening, diagnosis, or monitoring of PCa.

Racial and ethnic variation of PSA in global population: Age specific reference intervals for serum prostate specific antigen in healthy South Indian males

The serum PSA is universally accepted as the useful and clinically relevant tumor marker for monitoring therapy and identifying early recurrence in patients of carcinoma prostate throughout the world. However, application of serum PSA is limited to screening for early adenocarcinoma prostate among males above fifty years of age.Serum PSA concentration varies from one population to another in different parts of the world. Many groups of workers have selected 4 ng/ml of serum PSA as upper limit of normal range without giving due consideration for age specific increase in serum PSA. There is no single report available on normal decade wise age specific reference intervals for serum PSA in Indian males.The present study is undertaken to establish age specific reference intervals in healthy Indian males from 20-89 years belonging to subpopulation of Andhra Pradesh from South India. Our results revealed lowest concentration of 95 percentile serum PSA in Indian males compared to other populations globally. Contrary to this, healthy Afro Americans were found to have highest concentration of serum PSA compared to all other populations.

Prostate cancer diagnosed in spinal cord-injured patients is more commonly advanced stage than in able-bodied patients

OBJECTIVES

To determine the incidence and characteristics of prostate cancer in men with spinal cord injury (SCI). Little is known about the characteristics of prostate cancer in men with SCI, because prostate cancer screening is not aggressively performed in this population.

METHODS

In one fiscal year, 648 men with SCI older than age 50 years were actively enrolled with the SCI service, 20,949 able-bodied men older than age 50 years were actively enrolled in the outpatient clinic database, and 945 patients with prostate cancer were in the cancer registry at our facility. These three databases were cross-referenced for prostate cancer diagnosis and stage and compared with the presence of SCI.

RESULTS

Of the 648 patients with SCI, 12 patients with a prostate cancer diagnosis that preceded their injury were excluded. Of the remaining 636 patients, 11 (1.7%) had been diagnosed with prostate cancer since their injury. In contrast, of the 20,949 able-bodied men older than age 50 years seen at our facility in fiscal year 1999, 919 (4.4%) had prostate cancer. Of the patients with SCI and prostate cancer, 7 (63.6%) had locally advanced (Stage T3) or metastatic prostate cancer compared with 267 (29.1%) in the able-bodied population (P = 0.012).

CONCLUSIONS

Although the proportion of patients with a prostate cancer diagnosis was greater in the able-bodied patients, the prostate cancer detected in the patients with SCI tended to be of a more advanced stage and grade. The difference was likely a result of the decreased use of prostate cancer screening in this population.

Age-related reference ranges for complexed prostate-specific antigen and complexed/total prostate-specific antigen ratio: results from East Texas Medical Center Cancer Institute screening campaign

The East Texas Medical Center Cancer Institute conducted a regional prostate cancer screening campaign over a 3-year period from 1998 through 2000. Total prostate-specific antigen (tPSA), complexed PSA (cPSA), and cPSA/tPSA ratio (c/tPSA) values were determined. To better define prostate cancer in the population, we chose to determine age-based reference ranges for these PSA isoforms in apparently healthy men. Participants (N = 12,902) between the ages of 20 and 94 were screened and demographic information and serum tPSA and cPSA values were collected across 41 centers throughout East Texas. Men with an abnormal digital rectal examination, a follow-up biopsy indicating prostatic disease, or any clinical signs and symptoms of prostatic disease were excluded. Sera from 7541 evaluable men were tested with the Bayer Immuno 1 PSA and cPSA methods at East Texas Medical Center. The resulting PSA data were then stratified by decade of age to determine age-related reference ranges for each PSA species. The cPSA values increased across all age decades: 40 to 49 years, 1.45 ng/mL; 50 to 59, 1.92 ng/mL; 60 to 69, 2.49 ng/mL; and 70 to 79, 2.77 ng/mL (95th percentile). tPSA levels also increased with age: 1.81 ng/mL, 2.45 ng/mL, 3.17 ng/mL, and 3.57, respectively. Comparatively, the c/tPSA levels remained constant (0.87), regardless of age. The upper limits of tPSA and cPSA values reported here suggest that men should be screened using lower cutoff values than are currently in use. These limits may more accurately identify prostate cancer among otherwise healthy men.

Early response of prostate carcinoma xenografts to docetaxel chemotherapy monitored with diffusion MRI

For many anticancer therapies, it would be desirable to accurately monitor and quantify tumor response early in the treatment regimen. This would allow oncologists to continue effective therapies or discontinue ineffective therapies early in the course of treatment, and hence, reduce morbidity. This is especially true for second-line therapies, which have reduced response rates and increased toxicities. Previous works by others and ourselves have shown that water mobility, measured by diffusion-weighted magnetic resonance imaging (DW-MRI), increases early in tumors destined to respond to therapies. In the current communication, we further characterize the utility of DW-MRI to predict response of prostate cancer xenografts to docetaxel in SCID mice in a preclinical setting. The current data illustrate that tumor volumes and secreted prostate-specific antigen both respond strongly to docetaxel in a dose-responsive manner, and the apparent diffusion coefficient of water (ADC(w)) increases significantly by 2 days even at the lowest doses (10 mg/kg). The ADCw data were parsed by histogram analyses. Our results indicate that DW-MRI can be used for early detection of prostate carcinoma xenograft response to docetaxel chemotherapy.