Abstracts
Résumé
La découverte la plus conséquente de la deuxième moitié du xxe siècle dans le domaine du traitement du cancer de la prostate est probablement la mise en évidence que la prostate humaine, de même que de nombreux autres tissus périphériques, fabriquent localement une quantité importante d’androgènes à partir de précurseurs surrénaliens inactifs, essentiellement la déhydroépiandrostérone (DHEA) et son sulfate DHEA-S. Parallèlement à ces observations, deux autres découvertes importantes de notre groupe sont maintenant appliquées en clinique à travers le monde. Ainsi, les agonistes de la LH-RH (luteinizing hormone-releasing hormone) sont utilisés pour obtenir un blocage complet des androgènes d’origine testiculaire alors que, simultanément, les androgènes produits au niveau de la prostate à partir de la DHEA sont bloqués dans leur accès au récepteur des androgènes par un antiandrogène pur de la classe du flutamide. Ce traitement, appelé blocage androgénique combiné, est d’ailleurs le premier traitement démontré comme prolongeant la vie dans le cancer de la prostate. Alors que les premières études ont été effectuées chez des patients ayant un cancer avancé, nos données récentes indiquent un niveau d’efficacité remarquable de ce même traitement appliqué au stade localisé du cancer, avec une possibilité de guérison de l’ordre de 90%. Toutefois, afin de pouvoir traiter le cancer de la prostate au stade localisé, un diagnostic précoce est un prérequis. La première étude randomisée effectuée à grande échelle sur le dépistage du cancer de la prostate a démontré que 99% des cancers de la prostate peuvent être diagnostiqués au stade localisé ou potentiellement guérissable, grâce à la simple mesure annuelle de l’APS (antigène prostatique spécifique). Ainsi, la simple application des moyens diagnostiques et thérapeutiques actuellement disponibles peut faire en sorte que le décès dû au cancer de la prostate devienne une exception.
Summary
The most significant discovery of the second half of the xxth century in the field of prostate cancer therapy is probably the observation that the human prostate, as well as many other peripheral human tissues, synthesize locally an important amount of androgens from the inactive steroid precursors dehydroepiandrosterone (DHEA) and its sulfate DHEA-S. In parallel with these observations, two important discoveries also made by our group are applied in the clinic worlwide, namely the use of LHRH (luteininizing hormone-releasing hormone) agonists to completely block testicular androgens, while, simultaneously, the androgens made locally in the prostate from DHEA are blocked in their access to the androgen receptor by a pure antiandrogen of the class of flutamide. This treatment, called combined androgen blockade, has been the first treatment demonstrated to prolong life in prostate cancer. While the first studies were performed in patients with advanced and metastatic disease, our recent data indicate a remarkable level of efficacy of the same treatment applied to localized prostate cancer, namely a 90% possibility of cure. However, in order to be able to treat localized prostate cancer, early diagnosis must be achieved. In the first large-scale randomized study of prostate cancer screening, we have demonstrated that 99% of prostate cancers can be diagnosed at the localized or potentially curable stage, using simple annual measurement of PSA (prostatic specific antigen). Today’s data show that with the simple application of the available diagnostic and therapeutic tools, death from prostate cancer should be an exception.
Appendices
Références
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