經紫杉醇治療無效之轉移性去勢抗性攝護腺癌使用Abiraterone acetate治療成效的預測因子分析

Clinical predictor of efficacy of abiraterone acetate in metastatic castraction-resistence prostate cancer progressing after doxcetaxel treatment

張志鵬(Chin-Peng Chang)

指導教授 ： 楊順發

中山醫學大學/醫學院/醫學研究所/碩士(2016年)

摘要

研究背景
Abiraterone acetate已經證實在產生去勢抗性轉移性攝護腺癌病人，接受歐洲紫杉醇化學治療無效後，能增加整體存活率及疾病無惡化存活率。 此篇研究利用回溯性分析台灣本土病人的資料，找出臨床預測因子，藉此預測Abiraterone acetate的治療效果。
研究方法
從2012年1月年到2015年12月，利用回溯性病例分析，找出41個去勢抗性轉移性攝護腺癌病人，接受歐洲紫杉醇化學治療無效後，接著使用Abiraterone acetate的病人，我們紀錄了病人的基本資料，之前曾接受攝護腺手術或放射療法，曾接受過化學治療的種類及週期，接受Abiraterone acetat的治療時間，以及接受所有治療期間的攝護腺抗原指數的變化，然後將病人分成Abiraterone acetate治療後攝護腺抗原指數有反應組及Abiraterone acetate治療後攝護腺抗原指數無反應組，分析這兩組的相關因子，並分析與無疾病惡化存活率(progression free survival)跟整體存活率(overall survival)的關聯性，找出可預測Abiraterone aecetate治療效果的相關因子。
研究結果
在Abiraterone acetate治療後攝護腺抗原指數有反應組有24個病人(58.5%)，Abiraterone acetate治療後攝護腺抗原指數無反應組有17個病人 (41.5%)，在Abiraterone acetate治療後攝護腺抗原指數有反應組，可以發現有較好的疾病無惡化存活率(19.6 vs. 1.87個月, p<0.001)及整體存活率 (20.8 vs. 7.7 個月, p<0.002)，平均治療後攝護腺抗原指數達到最低值時間為3.7個月，與疾病無惡化存活率有關的預測因子為接受Abiraterone acetate治療前與診斷為去勢抗性攝護腺癌的攝護腺抗原指數進展比率， Abiraterone acetate治療前攝護腺抗原指數，Abiraterone acetate治療後攝護腺抗原指數最低值，及Abiraterone acetate治療前攝護腺抗原指數下降百分比，與整體存活率有關的臨床預測因子為被診斷去勢抗性轉移性攝護腺癌到接受紫杉醇化學治療的期間，及Abiraterone acetate治療前攝護腺抗原指數下降百分比。
結論
Abiraterone acetate在台灣病人中，可以達到不錯的治療效果，可以增加無疾病存活率及整體存活率，並且可以用接受Abiraterone acetate治療前與診斷為去勢抗性攝護腺癌的攝護腺抗原指數進展比率， Abiraterone acetate治療前攝護腺抗原指數，Abiraterone acetate治療後攝護腺抗原指數最低值，及Abiraterone acetate治療前攝護腺抗原指數下降百分比來預測整體存活率，以及用被診斷去勢抗性轉移性攝護腺癌到接受紫杉醇化學治療的期間，及Abiraterone acetate治療前攝護腺抗原指數下降百分比來預測整體存活率。
關鍵詞： 去勢抗性，轉移性攝護腺癌，雄性素，Abiraterone ，紫杉醇

關鍵字

去勢抗性 ； 轉移性攝護腺癌 ； 雄性素 ； Abiraterone ； 紫杉醇

並列摘要

BACKGROUND
Abiraterone acetate (AA) had been approved in the treatment of castration resistant prostate cancer (CRPC) after docetaxel. We performed a retrospective study in patients with mCRPC patients who received AA treatment after docetaxel and identify clinical predictor for the treatment outcome.

METHODS
From January 2012 to December 2015, 41 patients who received docetaxel after CRPC and followed by AA treatment were included in this chart reviewed study. The general status, including previous radical prostatectomy, radiation therapy, serum PSA level at each time-point, chemotherapy cycles, and AA treatment results were recorded. We divided patients into AA-PSA responder group and AA PSA non-responder group. Analyses of variable differences between two groups were performed and calculated into regression analysis. Analyses about progression-free survival and overall survival were also performed.

RESULTS
Twenty-four patients (58.5%) reached 50% PSA decrease and were selected into PSA responder group. The median PSA progression free survival and overall survival in total 41 patients were 6.2 and 18.9 months respectively. The AA PSA responder group had significant better median progression free survival and overall survival experienced (19.6 vs 1.87, p<0.0001; 20.8 vs 7.7, p=0.002 respectively). Median time to maximam PSA response was 3.7 months. The adverse events developed in 17 patients (41.5%) and most were grade 1/2. In univariate analysis for progression free survival, PSA at AA, PSA progression ratio, Nadir PSA after AA treatment and PSA decline percentage reached statistical significance. In overall survival, CRPC to chemotherapy duration and PSA decline percentage were significant predictors (p=0.0317 and p=0.021 respectively).

CONCLUSION
PSA at AA, and PSA progression ratio are clinical predictors for progression free survival before AA treatment. CRPC to chemotherapy duration can predict the overall survival outcome before AA treatment. PSA decline percentage can be used as a predictor after AA treatment in both progression free survival and overall survival.

並列關鍵字

abiraterone acetate ； castration resistant prostate cancer ； docetaxel ； predictor

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