前立腺生検適応患者を選択する上で,PSA densityとFree-to total PSA ratioの併用の有用性

Abstract

著者らが前立腺生検を行った428例を対象に, PSA density(PSAD)とFree-to total PSA ratio(F/T ratio)併用の有用性について検討した.その結果, PSADのカットオフを0.15, F/T ratioのカットオフを0.25に設定した場合, 両者の併用で1例の癌の見逃しもなく, 24例の不要な生検を除外できた可能性が示唆された.また, それぞれを単独で用いるよりも, 両者を併用したほうが, 良好な感度, 特異度が得られた

Prostate specific antigen (PSA) has been used an excellent diagnostic indicator, but its low cancer specificity has been pointed out. In this study, we investigated whether or not the use of Prostate specific antigen density (PSAD) in combination with free/total (F/T) ratio could improve biopsy indication in patients with abnormal PSA levels. Investigated were 428 patients undergoing prostate biopsy in our institution between January 2001 and September 2004, in which PSA levels were 4-20 ng/ml, and F/T ratio and prostate volume (hereinafter 'PV') could also be measured. At the cut-off values of 0.15 for PSAD and 0.25 for F/T ratio, the specificity and sensitivity were 37.7% and 85.5%, respectively, with PSAD alone; 20.1% and 91.8%, respectively, with F/T ratio alone; and 46.5% and 100%, respectively, with PSAD and F/T ratio. These results indicated that PSAD in combination with F/T ratio could also be an excellent biopsy indicator.