Prostate-specific Antigen Decline After 4 Weeks of Treatment with Abiraterone Acetate and Overall Survival in Patients with Metastatic Castration-resistant Prostate Cancer

详细信息    查看全文

• 作者：Pasquale Rescigno ; David Lorente ; Diletta Bianchini ; Roberta Ferraldeschi ; Michael P. Kolinsky ; Spyridon Sideris ; Zafeiris Zafeiriou ; Semini Sumanasuriya ; Alan D. Smith ; Niven Mehra ; Anuradha Jayaram ; Raquel Perez-Lopez ; Joaquin Mateo ; Chris Parker ; David P. Dearnaley ; Nina Tunariu ; Alison Reid ; Gerhardt Attard ; Johann S. de Bono ; ^{johann.de-bono@icr.ac.uk" class="auth_mail" title="E-mail the corresponding author}
• 关键词：Abiraterone acetate ; Metastatic castration-resistant prostate cancer ; Prostate-specific antigen
• 刊名：European Urology
• 出版年：2016
• 出版时间：November 2016
• 年：2016
• 卷：70
• 期：5
• 页码：724-731
• 全文大小：2222 K

文摘

The availability of multiple new treatments for metastatic castration-resistant prostate cancer (mCRPC) mandates earlier treatment switches in the absence of a response. A decline in prostate-specific antigen (PSA) is widely used to monitor treatment response, but is not validated as an intermediate endpoint for overall survival (OS).

Objective

To evaluate the association between early PSA decline and OS following abiraterone acetate (AA) treatment.

Design, setting, and participants

We identified mCRPC patients treated with AA before or after docetaxel at the Royal Marsden NHS Foundation Trust between 2006 and 2014. Early PSA decline was defined as a 30% decrease in PSA at 4 wk relative to baseline, and early PSA rise as a 25% increase.

Outcome measurements and statistical analysis

Association with OS was analyzed using multivariate Cox regression and log-rank analyses. Spearman's rho correlation coefficient (r) was calculated to evaluate the association between PSA changes at 4 wk and 12 wk.

Results and limitations

There were 274 patients eligible for this analysis. A 30% PSA decline at 4 wk was associated with longer OS (25.8 vs 15.1 mo; hazard ratio [HR] 0.47, p < 0.001), and a 25% PSA rise at 4 wk with shorter OS (15.1 vs 23.8 mo; HR 1.7, p = 0.001) in both univariate and multivariable models. The percentage PSA decline at 4 wk was significantly correlated with the percentage PSA change at 12 wk (r = 0.82; p < 0.001). Patients achieving a 30% PSA decline at 4 wk were 11.7 times more likely to achieve a 50% PSA decrease at 12 wk (sensitivity 90.9%, specificity 79.4%). Limitations include the retrospective design of this analysis.

Conclusions

Patients not achieving 30% PSA decline after 4 wk of AA have a lower likelihood of achieving PSA response at 12 wk and significantly inferior OS. Prospective multicentre validation studies are needed to confirm these findings.

Patient summary

Prostate-specific antigen (PSA) is commonly used to evaluate response to treatment in metastatic castration-resistant prostate cancer. Expert recommendations discourage reliance on PSA changes earlier than 12 wk after treatment initiation. Our data suggest that early PSA changes are associated with survival in patients receiving abiraterone acetate.