Does prostate specific antigen density correlates with aggressiveness of the prostate cancer?

Abstract

Background: As already documented, a high prostate specific antigen in men with normal size of prostate gland is more likely to be associated with an aggressive cancer as compared to others with the same prostate specific antigen and a large gland size. In this retrospective study we tested the association between Prostate Specific Antigen Density (PSAD) and tumor aggressiveness in patients with clinically localized Prostate Cancer (PCa) surgically treated by radical prostatectomy.

Methods: We evaluated data from patients records in a cohort of 72 patients who underwent radical prostatectomy between January 2000 and June 2007. PSAD was calculated as ratio between the preoperative total prostatic specific antigen (PSA) in nanograms per milliliter with the prostate weight (PW) of prostatectomized specimen in grams or prostate volume measured with ultrasound (US). The patients were stratified into four PSAD categories: 0.1-0.15, 0.16- 0.20, 0.21-0.5 and greater than 0.51 ng/ml/gr. Parameters that were included into analysis were: PSA, measurement of the prostate volume by ultrasound (preoperatively) and prostate weight, pathological tumor stage, Gleason sum, Gleason grade, metastatic lymph nodes, seminal vesicle involvement and organ confine disease (postoperatively). Worsening of the clinicopathological properties was defined as aggressiveness.

Results: There was a significant correlation between US-PSAD and PW-PSAD (p<0.001). In US-PSAD categories the statistic tests found significant correlation with the primary tumor (R=0.303, p<0.01), metastatic lymph nodes (R=0.331, p<0.01), and the organ confine disease (R=0.296, p<0.05). The PW-PSAD categories correlated significantly with the pathologic findings from other parameters. Hence, a statistically significant correlation was found with Gleason sum (R=0.246, p<0.05), Gleason grade (R=0.234, p<0.05), primary tumor (R=0.285, p<0.05), metastatic lymph node (R=0.287, p<0.05) and organ confine disease (R=0.303, p<0.01).

Conclusions: Prostate specific antigen density measurement is useful tool for the assessment of the degree of aggressiveness in clinically localized prostate cancer, and further investigation regarding its possible use as a prediction marker is justified.

Keywords: aggressiveness of prostate cancer; prostate-specific antigen; prostatic cancer.