Cancer de la prostate localisé à haut risque: Définition, pronostic et traitement

According to d'Amico's criteria, high-risk localized prostate cancer are defined either by an extracapsular extension (T3 or T4), either by a high Gleason score (> 7) or a PSA rate higher than 20 ng/ml. Pelvic lymph node involvment also corresponds to locally advanced prostate cancer. Statistical models called nomograms have been developed to predict the probability of prostate cancer recurrence and are also used to define locally advanced patients. Prostate MRI may help to detect an extracapsular extension or a seminal vesicles involvment but remains still discussed. A bone scan, an abdominal and pelvic CT scan have to be performed in order to detect metastases. A pelvic lymph node dissection is recommended in order to adapt the treatment of these patients. Standard treatment for high-risk localized prostate cancer without lymph node involvment is now well defined. The association of both local radiation and a long androgen deprivation (GnHR agonist) showed an overall survival benefit (more than 10 %). The radiation dose of 74 Gy is recommended. Other questions are still debating : the optimal duration of the hormonotherapy , the use of the bicalutamide 150 mg instaead of GnRH agonists, the optimal radiation dose. Radical prostatectomy is no more considered as a standard treatment for these patients. Since the use of chemotherapy for metastatic patients showed a benefit in overall survival, the place of chemotherapy as adjuvant or neo-adjuvant treatment is questionned in several randomized phase III studies. Sometimes high-risk disease is diagnosed after performance of a radical prostatectomy. A postoperative radiation may be performed in order to decrease clinical and biochemical progression. The use of bicalutamide 150 mg in this situation may have a positive impact too on progression free survival. In case of lymph node involvment, androgen deprivation is the standard treatment with an overall survival benefit. The place of local radiation therapy is still debating.