Presentation Authors: Youness AHALLAL*, Nice, France, Nicole Benfante, New York, NY, Matthieu Durand, Nice, France, Luis Felipe Snel Zanettini, Christiane Strauss, Alexandre Colau, Paris, France, Karim Touijer, New York, NY, Bertrand Guillonneau, Paris, France
Introduction: Patients with intermediate-risk prostate cancer (IR-PC) belong to a heterogeneous group with highly variable prognoses. The objective was to determine the pre-operative predictors of unfavorable oncological outcomes in IR-PC patients treated with radical prostatectomy and extended pelvic lymphadenectomy (RP-eLND) and compare oncological outcomes of unfavorable IR-PC to high-risk prostate cancer (HR-PC) patients.
Methods: Between 01/2012 and 02/2017, 2262 IR-PC and 981 HR-PC patients were consecutively included. Data were prospectively collected and extracted from our two institutional databases.Multivariate logistic regression analysis (MLRA) was used with forward stepwise variable selection to assess predictors of biochemical recurrence (BCR) and to define an unfavorable subgroup. Primary endpoint was BCR-free survival.
Results: 11% of IR-PC patients experienced BCR after 18.1 (8.2-62.1) months median follow-up. On MLRA assessing biopsy Gleason Score, number of positive biopsy cores (PBC) out of 12, bilaterality of lesions and extraprostatic extension on prostate MRI, only PBC â‰¥4 predicted disease recurrence (p=0.0002). In unfavorable IR-PC and HR-PC group respectively, 81% and 62% were disease-free after 18 (7.4-33.6) and 17.2 (5.3-31.7) months median (IQR) follow-up. When adjusted for pre-operative PSA, the unfavorable IR-PC group had still better oncological outcomes when compared to the HR-PC group in terms of BCR-free survival: HR: 3.40 (95% CI 2.90, 3.98; p < 0.0001)
Conclusions: According to our model, among patients with IR-PC, a number of PBC â‰¥4 out of 12 had a statistically significant correlation to adverse oncological outcomes. This subgroup of unfavorable IR-PC demonstrated worst oncological outcomes when compared to those of favorable IR-PC patients and still had better ones when compared to those of HR-PC patients treated with RP-ePLND. To our knowledge, this is the first study to stratify the IR-PC group into favorable and unfavorable subgroups according to BCR-free survival. These results are important to consider when counselling such patients for their disease management.