Managing metastatic castration-resistant prostate cancer (mCRPC) in men aged ≥ 75 is challenging due to limited data. Regardless of age, in real-world clinical practice, most mCRPC still derive from failure of androgen deprivation therapy (ADT) with or without docetaxel (D) for metastatic castration-sensitive prostate cancer (mCSPC). As abiraterone acetate plus prednisone (AA) and enzalutamide (Enza) are common first-line treatments for mCRPC. The impact of prior use of D for mCSPC on the efficacy and safety of AA or Enza in this older population remains unclear.
A cohort of patients aged ≥ 75 years starting AA or Enza as first-line therapy for mCRPC from January 2015 to April 2019 was identified from the registries of 10 institutions. Patients were categorized into 2 groups based on previous use of D for mCSPC. Primary endpoints were cancer-specific survival (CSS) from AA or Enza start, CSS from ADT onset, and safety. We used Kaplan-Meier method to estimate the endpoints distribution, including median values with 95% confidence intervals (95% CI).
Of the 337 patients identified, 24 (7.1%) received ADT+D and 313 (92.9%) received ADT alone for mCSPC. Median follow-up from AA/Enza start was 18.8 months. Median CSS from ADT or AA/Enza was not significantly different between ADT+D and ADT alone cohorts (71.9 vs. 52.7 months, P = .97; 25.4 vs. 27.2 months, P = .89, respectively). No statistically significant difference in adverse events (AEs) of any grade rate (58.3% vs. 52.1%, respectively; P = .67) or grade ≥ 3 (12.5% vs. 15.7%, respectively; P = 1.0) was found between ADT+D and ADT alone cohorts.
Despite the innate limitations of a retrospective design and relatively small size of the ADT+D cohort, this analysis suggests that elderly men receiving AA or Enza as first-line therapy for mCRPC have similar survival outcomes and tolerability, regardless of previous D for mCSPC.
Clinical genitourinary cancer. 2024 Aug 09 [Epub ahead of print]
Giuseppe Fotia, Calogero Saieva, Richard Lee-Ying, Anna Patrikidou, Pier Vitale Nuzzo, Elisa Zanardi, Sabrina Rossetti, Matthew Davidsohn, Marc Eid, Talal El Zarif, Heather McClure, Gian Paolo Spinelli, Alessandra Damassi, Veronica Murianni, Charles Vauchier, Thiago Martins Oliveira, Andrea Malgeri, Mikol Modesti, Ricardo Pereira Mestre, Loana Valenca, Praful Ravi, Daniele Santini, Sandro Pignata, Ugo De Giorgi, Christopher Sweeney, Daniel Heng, Giuseppe Procopio, Antonio Russo, Edoardo Francini, Spartacuss Group
Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy., Cancer Risk Factors and Lifestyle Epidemiology Unit - ISPRO, Florence, Italy., Department of Oncology, University of Calgary Tom Baker Cancer Centre, Tom Baker Cancer Centre, Calgary, Alberta, Canada., Department of Medical Oncology, Gustave Roussy Institute, Villejuif, France., Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY., Medical Oncology Unit 1, IRCCS Ospedale Policlinico San Martino, Genova, Italy., IRCCS Istituto Nazionale dei Tumori Fondazione G. Pascale, Naples, Italy., Lank Center for Genitourinary Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA., Division of Medical Oncology, Casa della Salute di Aprilia, Latina, Sapienza University of Rome, Italy., Instituto D'Or de Pesquisa e Ensino, Salvador, Brazil., Fondazione Policlinico Campus Bio-Medico di Roma, Rome, Italy., Oncology Institute of Southern Switzerland, Bellinzona, Switzerland., Oncology Unit, Umberto I hospital, Rome, Italy., IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) Dino Amadori, Meldola, Italy., South Australian Immunogenomics Cancer Institute, University of Adelaide, Adelaide, Australia., Department of Surgical, Oncological and Oral Sciences, Section of Medical Oncology, University of Palermo, Palermo, Italy., Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy. Electronic address: .