從接受攝護腺切片病人的攝護腺特異抗原、肛門指診以及經直腸超音波研究前列腺切片之適應性

Evaluation the contribution of PSA, DRE and TRUS in prostate biopsy

鄭皓碩(Hao-Shuoh Jeng)

指導教授 ： 黃俊雄

高雄醫學大學/醫學院/醫學研究所/碩士(2004年)

摘要

在2002年攝護腺癌已經高居十大癌症的第七位，雖然發生率比起美國仍低，但卻有逐年升高的趨勢。在美國，攝護腺癌的篩檢建議是每年攝護腺特異抗原加上肛門指診，但由於族群不同，在不同國家及醫師對於切片與否一直有著不同的意見。因此我們在七年內收集了300位接受肛門指診、經直腸超音波、攝護腺特異抗原以及接受經直腸攝護腺切片的病人資料，我們分析切片病人的資料，來研究攝護腺特異抗原、肛門指診以及經直腸超音波的陽性預測值，以達到能避免不必要的切片又不會造成攝護腺癌病人遺漏的情形，而且我們也研究攝護腺特異抗原、肛門指診以及經直腸超音波都異常病人的陽性預測值。
研究樣本平均年紀為71歲，攝護腺特異抗原的平均值為9.8ng/ml，總共有263位病人攝護腺特異抗原異常、137位病人肛門指診異常、以及133位病人經直腸超音波異常。在第一次切片的樣本中，有5位攝護腺癌的病人則在第二次切片診斷出來；另外有2位攝護腺癌的病人是因為經尿道攝護腺刮除手術時診斷出來。所有攝護腺癌病人的Gleason score分佈是44位小於等於6，5位等於7，10位大於等於8，而臨床分期分佈則是20位T1cN0M0, 30位T2N0M0以及9位T3N0M0。我們的研究結果發現攝護線特異抗原介於4~10ng/ml、攝護腺特異抗原大於10ng/ml、肛門指診以及經直腸超音波的陽性預測值分別為12%、45%、17%以及11%，如果使用肛門指診異常合併攝護線特異抗原介於4~10ng/ml之間，會得到最高的陽性預測值而且遺漏最少的攝護腺癌病人。相反的在攝護腺特異抗原大於10ng/ml的病人中，合併肛門指診或是經直腸超音波都沒有辦法提高陽性預測值而不至遺漏太多攝護腺癌病人。
在第二次切片的研究樣本中，攝護腺癌臨床分期、病理分級、陽性預測值都跟第一次切片的病人臨床分布一樣。在這些病人中，當攝護腺特異抗原以及肛門指診都異常時建議病人切片，可以得到最好的陽性預測值及減少不必要的切片數。
與攝護腺癌病人最相關的是骨頭疼痛的症狀，雖然最多的攝護腺癌症狀是下泌尿道症狀，但這在攝護腺癌及非攝護腺癌的病人比例相似，只有骨頭疼痛在攝護腺癌的病人中比例高於非攝護腺癌的病人，這可能與攝護腺癌容易轉移至骨頭有關。

關鍵字

攝護腺特異抗原 ； 肛門指診 ； 經直腸超音波 ； 攝護腺切片

並列摘要

Prostate cancer has become the 7th most common malignancy in Taiwan in 2002. In American, regular prostate specific antigen (PSA) and digital rectal examination (DRE) yearly are recommended for prostate cancer screening. Because of different incidence and risks in different population, vary viewpoints to biopsy among the clinician and race. A total of 300 patients over 7-year period had prostate biopsy, whom received DRE, transrectal ultrasound (TRUS), and PSA tests, respectively. We collected our results and compared positive predictive value in PSA, DRE and TRUS separately for preventing unnecessary biopsy and delay in diagnosis. Then we also combined PSA, DRE and TRUS to evaluate the positive predictive value.
The mean age of the biopsy population is 71 years old. The mean PSA level is 9.8ng/ml. Total 263 patients had abnormal PSA level, 137 patients had abnormal DRE and 133 patients had abnormal TRUS findings. Fifty-two patients were diagnosed as prostate cancer in 1st biopsy, 5 patients in 2nd biopsy and 2 patients of prostate cancer were diagnosed after TURP. The distribution of pathologic grade and clinical stage is 44 patients grade ≦6, 5 patients grade 7 and 10 patients≧8; 20 patients T1cN0M0, 30 T2N0M0 and 9 T3N0M0. The positive predictive value in biopsy patients is 12% of PSA between 4~10ng/ml, 45% in PSA> 10ng/ml, 17% of abnormal DRE examinations, and 11% of abnormal TRUS findings. The positive predictive value increased mostly in the combination of abnormal DRE examinations with PSA between 4~10ng/ml. But the positive predictive value did not increase in combination of abnormal DRE or TRUS examinations with PSA >10ng/ml. The miss of prostate cancer occurred least in the combinations of PSA between 4~10ng/ml and abnormal DRE examinations.
In the population of 2nd biopsy, the clinical distribution of prostate cancer in patients was same as 1st biopsy population. Abnormal PSA levels combined abnormal DRE examinations produce the highest positive predictive value. By doing so, miss of prostate cancer will not occur and the biopsy numbers can be reduced.
The most correlation of clinical symptoms is bone pain. The symptoms occupy larger fraction in prostate cancer than no cancer populations. The cause may be due to easy bone metastasis by prostate caner.

並列關鍵字

DRE ； PSA ； prostate biopsy ； TRUS

參考文獻

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