ABSTRACT Objective: We aimed to investigate the prognostic significance of intraductal carcinoma in radical prostatectomy (RP) specimens and predictive value of IDC-P for biochemical recurrence and adjuvant therapy decision. Method: Patients who underwent RP between 2000-2014 with final pathological stage pT3a and negative surgical margins (Group 1, n=35) and pT2 with positive surgical margins (Group 2, n=32) were included. RP specimens were re-evaluated for the presence of IDC-P component and other prognostic factors. In both groups, prognostic factors were compared according to the presence of IDC-P and biochemical recurrence status. Results: In group 1, IDC-P was detected in 5 cases and biochemical recurrence was detected in 3 cases. Patients with IDC-P showed significantly higher biochemical recurrence than those without IDC-P (p=0.002). In univariate analysis, IDC-P was found to be significantly associated with worse progression free survival (p<0.001). In group 2, IDC-P was detected in 4 cases and biochemical recurrence was detected in 10 cases. Also, tumor volume was significantly higher in patients with IDC-P than those without IDC-P (p=0.02). IDC-P was also significantly associated with worse progression free survival in group 2 (p=0.033). Conclusions: In both groups, IDC-P is a prognostic factor for progression free survival and / or biochemical recurrence. Especially in these patients, presence of IDC-P might be helpful for postoperative adjuvant therapy management decision. Keywords: radical prostatectomy, intraductal carcinoma of prostate (IDC-P), prostate cancer, biochemical recurrence, progression free survival.