e23405 Background: Prostate cancer accounts for 14% of cancers in men in Peru. Although abiraterone acetate was approved by the FDA in 2011, access through the Peruvian public health system has been available only since 2022, raising questions about its real-world effectiveness in both metastatic castration-sensitive (mCSPC) and castration-resistant prostate cancer (mCRPC). Our objective was to describe the clinicopathological characteristics and outcomes of patients treated with abiraterone across metastatic prostate cancer settings in 4 oncology centers nationwide in Peru. Methods: A retrospective cohort study of patients with metastatic prostate cancer treated with abiraterone at 4 oncology centers in Peru: Instituto Nacional de Enfermedades Neoplásicas (INEN), Instituto Regional de Enfermedades Neoplásicas del Sur (IREN SUR), Hospital Centro Médico Naval (CEMENA), and Hospital Regional Guillermo Díaz de la Vega (HRGDV), between 2022-2025. Descriptive statistics and Kaplan–Meier methods were used to assess clinicopathological characteristics, radiographic progression-free survival (rPFS), and overall survival (OS). Results: 113 patients were included. Abiraterone acetate was used in mCSPC setting in 30% (mean age 71.5 years; mean PSA 166 ng/mL) and in mCRPC setting in 70% (mean age 71.2 years; mean PSA 2,535 ng/mL). Histology was acinar adenocarcinoma in mCSPC:97.1% and mCRPC: 93.7%. Gleason score distribution in mCSPC was: 1:2.9%; 2:2.9%; 3:17.6%; 4: 44.2%; 5: 29.5%; unknown:2.9%, in mCRPC: 1:2.5%; 2:11.4%; 3: 21.5%; 4: 25.3%; 5:32.9%; unknown:6.3%. By LATITUDE risk classification, mCSPC patients were high risk 44.1% and low risk 55.9%. The main metastatic sites in mCSPC were bone 85.3%, nodal 47.1%, and visceral 14.7%; in mCRPC bone 92.4%, nodal 35.4%, and visceral 10.9%. In mCSPC, treatment comprised triplet therapy (abiraterone–docetaxel–ADT): 2.9% and doublet therapy (abiraterone–ADT): 97.1%. In mCRPC, prior treatments were bicalutamide–ADT 72.2%, docetaxel–ADT 16.5%, and ADT alone 11.3%. RECIST response in mCSPC showed partial response (PR): 88.2%, complete response (CR): 5.9%, and progressive disease (PD):5.9%. In first-line mCRPC, abiraterone: 65.8%, docetaxel:29.1% and palliative care: 5.1%. RECIST responses comparing abiraterone versus docetaxel were: abiraterone PR 41.3%, PD 16.0%, stable disease (SD) 12.0%; docetaxel PR 14.7%, PD 13.3%, SD 2.7%. With a median follow-up of 41.3 months, 3 years rPFS was mCSPC: not reached; mCRPC rPFS at 3 years was 43.4% in the pre-docetaxel setting and 4.3% post-docetaxel. 3 years OS was mCSPC: 90.7% and mCRPC 80.1%. Conclusions: In real-world practice in Peru, abiraterone demonstrated efficacy and survival comparable to pivotal trials, with superior outcomes in mCSPC. Despite 44% high-risk disease, triplet therapy was rarely used and most patients received ADT alone or with bicalutamide, limiting its population-level benefit.
Lugo et al. (Thu,) studied this question.