BACKGROUND: A prostate-specific antigen (PSA) flare occurs in about 15% of metastatic castration-resistant prostate cancer (mCRPC) patients receiving docetaxel.
This flare has no standard definition. Its impact on treatment efficacy is unclear. We sought to evaluate the incidence and characteristics of PSA flare on cabazitaxel, and its impact on survival.
METHODS: Multicentre retrospective review of consecutive patients treated with cabazitaxel second-line chemotherapy for mCRPC. Collection of baseline characteristics, disease history and PSA levels before and during cabazitaxel therapy. Overall survival (OS) and radiological/clinical progression-free survival (PFS) for patient groups corresponding to different definitions of PSA flare estimated by the Kaplan-Meier method and compared using the log-rank test.
RESULTS: Overall, 125 patients were included. Median PFS and OS were 6.5 and 13.3months, respectively. Depending upon the definition used, flare incidence ranged from 8.3% to 30.6%. The flare lasted < 2.6months. A PSA flare followed by a ⩾50% decrease was associated with a median PFS and OS of 11.2 and 25.2months, respectively. Median PFS and OS for a ⩾30% rather than ⩾50% decrease were 10.4 and 16.5months. These outcomes were not significantly different from those in patients with immediate PSA decreases of ⩾50% or ⩾30% from baseline, but were significantly better than in patients experiencing no PSA decrease (p=0.006 and 0.015, respectively, for OS).
CONCLUSION: The PSA response to cabazitaxel, with or without initial flare, was associated with a strong survival benefit. The taxane-induced flare during the first 12weeks of therapy can be ignored when evaluating PSA response.
Written by:
Angelergues A, Maillet D, Fléchon A, Ozgüroglu M, Mercier F, Guillot A, Le Moulec S, Gravis G, Beuzeboc P, Massard C, Fizazi K, de La Motte Rouge T, Delanoy N, Elaidi RT, Oudard S. Are you the author?
Department of Medical Oncology, Georges Pompidou European Hospital, Paris, France; Department of Medicine, Centre Léon Bérard, Lyon, France; Department of Internal Medicine, Istanbul University Hospitals, Istanbul, Turkey; Stat Process, Port-Mort, France; Department of Medicine, Institut de Cancérologie de la Loire, Saint-Etienne, France; Department of Medical Oncology, Val de Grace Hospital, Paris, France; Department of Medicine, Institut Paoli Calmettes, Marseille, France; Department of Medicine, Institut Curie, Paris, France; Department of Cancer Medicine, Institut Gustave Roussy, University of Paris Sud, Villejuif, France; Department of Medical Oncology, Pitié-Salpêtrière Hospital, Paris, France.
Reference: Eur J Cancer. 2014 Apr 8. pii: S0959-8049(14)00270-6.
doi: 10.1016/j.ejca.2014.03.015
PubMed Abstract
PMID: 24725337
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