背景與動機:隨著人口老化與飲食西化等因素影響,國人攝護腺癌的盛行率與死亡率逐年增加,自1980後期經直腸攝護腺超音波切片(Transrectal Ultrasonography Guilded Prostate Biopsy,TRUS Bx)已成為診斷攝護腺癌普遍使用的標準檢查流程,但隨之而來的檢查合併症與醫療花費亦不容忽視,本研究主要目的為透過血清攝護腺抗原(Prostate-Specific Antigen,PSA)所衍生出的數值,探討最有效的篩選工具,以降低病人接受不必要的攝護腺超音波切片檢查。 材料與方法:取自台中榮民總醫院2年內(自2009年2月至2011年1月)接受攝護腺切片檢查患者PSA值介於4-10ng/ml共計445檢次,分析血清攝護腺抗原密度(PSA Density,PSAD)、游離態血清攝護腺抗原比率(free to total PSA ratio,f/t PSA ratio)、肛門指診(Digital Rectal Examination,DRE)異常與否及經直腸攝護腺超音波(Transrectal Ultrasonography,TRUS)異常與否,等相關預測工具對於罹患攝護腺癌的預測。 結果:總樣本平均年齡為65.1歲±10.47(27-89歲),預測工具優劣結果依序為:f/t PSA ratio>PSAD>DRE>TRUS。統計分析比較,f/t PSA ratio≦0.17有最高的敏感度=82.9%,而其特異度=45.7%,為本研究最佳的單一攝護腺癌預測切點。若綜合二種以上預測工具以f/t PSA ratio≦0.17合併DRE可得最佳的敏感度=94.3%及可接受的特異度=35.0%。 結論:f/t PSA ratio是單一預測工具中可得最佳的癌症預測能力,我們應針對PSA為4-10ng/ml病人採集free PSA指數,並搭配肛門指診篩檢攝護腺癌。
Background:With the impact factor of aging population and the westernization of diet, the prevalence and mortality rate of people with prostate cancer increase annually. Since 1980 transrectal ultrasonography guilded prostate biopsy (TRUS Bx) has become a standard and common procedure for diagnosis of prostate cancer. However, the complications and medical costs accompanying inspection should not be ignored. The main purpose of this study is that how to use the parameter which are derived from the serum prostate-specific antigen (PSA) to explore the most effective screening tool to reduce unnecessary biopsies for prostate cancer patients. Materials and methods: Within 2 years (from February 2009 to January 2011) 445 inspection times are collected from the patients who accepted prostate biopsy and PSA values between 4-10ng/ml at Taichung Veterans General Hospital. By analyzing serum prostate-specific antigen density (PSAD)、free to total serum prostate-specific antigen ratio(f/t PSA ratio)、digital rectal examination(DRE)、transrectal ultrasonography (TRUS) for predicting prostate cancer. Results:The average age was 65.1 ± 10.47years old (range: 27-89 years). The prediction parameter from the best to the worst for prostate cancer was f/t PSA ratio> PSAD> DRE> TRUS. Statistic analysis and comparison, f/t PSA ratio≦0.17 was the best single cut-off point for prediction of prostate cancer with the best sensitivity=82.9% and specificity=45.7%. If combination of two or more prediction parameters, f/t PSA ratio≦0.17 combined with DRE, have the best sensitivity = 94.3% and acceptable specificity = 35.0%. Conclusion: f / t PSA ratio can get the best predictive ability for prostate cancer within single parameters. Free PSA of the serum should be collected for patients with PSA as 4-10ng/ml and combined DRE for screening prostate cancer.