Evaluation of [−2] proPSA and Prostate Health Index (phi) for the detection of prostate cancer: a systematic review and meta-analysis

Abstract

The usefulness of %[ − 2] proPSA and Prostate Health Index (phi) in the detection of prostate cancer are currently unknown. It has been suggested that these tests can distinguish prostate cancer from benign prostatic diseases better than PSA or %fPSA. We performed a systematic review and meta-analysis of the available scientific evidence to evaluate the clinical usefulness of %[ − 2] proPSA and phi. Relevant published papers were identified by searching computerized bibliographic systems. Data on sensitivity and specificity were extracted from 12 studies: 10 studies about %[ − 2] proPSA (3928 patients in total, including 1762 with confirmed prostate cancer) and eight studies about phi (2919 patients in total, including 1515 with confirmed prostate cancer). The sensitivity for the detection of prostate cancer was 90% for %[ − 2] proPSA and phi, while the pooled specificity was 32.5% (95% CI 30.6 -34.5) and 31.6% (95% CI 29.2 -34.0) for %[ − 2] proPSA and phi, respectively. The measurement of %[ − 2] proPSA improves the accuracy of prostate cancer detection in comparison with PSA or %fPSA, particularly in the group of patients with PSA between 2 μ g/L and 10 μ g/L. Similar results were obtained measuring phi. Using these tests, it is possible to reduce the number of unnecessary biopsies, maintaining a high cancer detection rate. Published results also showed that %[ − 2] proPSA and phi are related to the aggressiveness of the tumor.

PSA, PSA derivatives, proPSA and prostate health index in the diagnosis of prostate cancer

“…Whereas, p2PSA was the most stable form in serum. [14] In many studies related to proPSA, rates for tPSA/pPSA, pPSA/ sPSA, pPSA/sPSA/tPSA, and pPSA/BPSA have been determined. For example, Khan et al [32] indicated that in cases with tPSA values ranging between 4, and 10 ng/mL, pPSA levels measured in order to refrain from unnecessary biopsies had 90% sensitivity, and 44% specificity.…”

“…In a few studies performed in patients with tPSA levels of 2.5-10 ng/mL, in the discrimination between PCa, and BPH, p2PSA/fPSA ratio was reportedly more meaningful as for detection of PCa relative to tPSA or % fPSA. [14] Naya et al [37] , indicated lack of any significant difference between patients with or without PCa as for pPSA values, and % pPSA within a tPSA interval 4.4-8.5 ng/mL. Catalona et al [38] observed increases in % pPSA values in PCa patients with tPSA values varying between 2, and 10 ng/mL, and stated that % pPSA has higher diagnostic sensitivity, and specificity for PCa when compared with % fPSA without any correlation between histopathological stage, and % pPSA.…”

“…BPSA, and iPSA have been associated with benign tissue, while proPSA was found in prostate cancer tissue. [14] Especially in men with PSA levels ranging between 4, and 10 ng/mL, f/tPSA is more sensitivity in discriminating PCa from benign tissues. [15] In a prospective multicentered study % f/tPSA values of <10%, and >25% could detect PCa in 56, and 8% of the patients, respectively.…”

PSA, PCA3 and thephilosophy of prostate cancer management

“…Although the term derivative may evoke some distrust, in laboratory medicine, in contrast to the financial world, derivative tests are based on solid scientific foundations and are useful in aiding diagnosis. [18]. It has been demonstrated that despite costs associated with the procedure, the utilization of %[-2] proPSA or phi is cost-effective and reduces the global costs.…”

“…In addition to the review on [-2] proPSA and phi by Filella and Gimenez [ 18 ], other papers in the current issue of Clinical Chemistry and Laboratory Medicine illustrate the philosophy behind tumor marker utilization in the management of prostate cancer as well as other tumors. Two papers address different methodological issues of PSA determination.…”