Predicting abiraterone efficacy in advanced prostate cancer: Insights from marker of proliferation Ki-67.

• DOI: 10.1200/jco.2024.42.4_suppl.176
• Publication Date: 2024-01-29T21:06:41Z
• Authors: Fengnian Zhao; Jinge Zhao; Yifu Shi; Xinyuan Wei; Ni Chen; Pengfei Shen; Hao Zeng
• Keywords: Abiraterone; Abiraterone acetate

176 Background: The marker of proliferation Ki-67 (KI67) is a well-known biomarker reflecting cell activity and was reported to be associated with the treatment efficacy chemotherapy in different tumors. However, it unknown whether KI67 also has role predicting next-generation hormone therapies, e.g., abiraterone, for patients prostate cancer (PCa). Methods: Clinicopathological data 144 men metastatic PCa who received abiraterone therapy were retrospectively collected. positivity examined by immunohistochemistry (IHC) using biopsy specimen. predictive value other factors on therapeutic explored. Kaplan-Meier curve COX regression analysis used survival analysis. endpoints PSA progression-free (PSA-PFS) radiographic (rPFS) according PCWG3 criteria. Results: Among included patients, 82 (56.9%) 62 (43.1%), respectively, at hormone-sensitive (mHSPC) castration-resistant (mCRPC) stage. median 20% total cohort (interquartile range: 10%-30%). When taken as continuous variable, adversely related both PSA-PFS (HR, 95%CI: 1.02, 1.01-1.03, P=0.001) rPFS 1.02-1.03, therapy, while not response. results multivariate implied that, after adjusting mHSPC/mCRPC stage, ISUP grading, pain score, visceral metastasis, burden, still an independent predictor P=0.008) therapy. Moreover, when divided into two groups high low KI67, cutoffs 10%, 20%, 30%, remained significant (HR: 1.67, 1.91, 2.29; P value: 0.052, 0.004, <0.001) 1.54, 1.83, 1.88; 0.119, 0.008, 0.008) treatment. Subgroup based mHSPC or mCRPC stage suggested that 30% (median PSA-PFS: 11.4- vs. 27.6-Mo, P<0.001; rPFS: 16.6- 33.6-Mo, optimal cutoff maximize patient prognostic differentiation cohort, 6.9- 14.9-Mo, P=0.033; 10.1- 16.5-Mo, P=0.030) cohort. Conclusions: Our study revealed specimens robust advanced PCa. Further validation datasets from centers needed strengthen findings our work.