Incidence and Clinicopathological Characteristics of Intraductal Carcinoma of the Prostate Detected in Prostate Biopsies: A Prospective Cohort Study
Katherine E Watts, Jianbo Li, Christina Magi-Galluzzi, Ming Zhou. Cleveland Clinic, Cleveland, OH
Background: Intraductal carcinoma of the prostate (IDC-P) is a distinct clinicopathological entity characterized by expansile proliferation of cancer cells within preexisting prostatic ducts and acini. It is strongly associated with aggressive high grade and high volume prostate cancer (PCa). It is critical to recognize IDC-P, especially in prostate biopsy (PBx). We aimed to study the incidence and clinicopathological characteristics of IDC-P detected in PBx in prospectively collected cases.
Design: IDC-P was defined as a lumen-spanning proliferation of malignant cells within prostatic glands with at least partial basal cell lining. From November 2009 to September 2011, PBx with IDC-P were prospectively collected and their clinicopathological features evaluated.
Results: 33 IDC-P cases were identified out of 1176 PBx (2.8%), including 3 (9%) cases without an associated invasive PCa, 16 (48%) associated with Gleason score 7 (GS 7) PCa, 4 (12%) with GS 8 PCa, and 10 (30%) with GS 9 PCa. The mean age of IDC-P patients was 65 (range 46-79) years and mean serum PSA was 16.2 (range 0.4-105.6) ng/mL. The mean number of biopsy cores involved by PCa was 7.2 (range 1-14). Treatment information was available in 30 patients: 19 men were treated with non-surgical therapy, including radiation, androgen deprivation and chemotherapy; 9 underwent radical prostatectomy (RP). Extraprostatic extension (EPE), seminal vesicle invasion (SVI) and lymph node metastasis (LN) was observed in 6/9 (67%), 4/9 (44%) and 1/9 (11%), compared to the predicted mean risk of 41%, 12% and 5% for EPE (p=0.173), SVI (p=0.002) and LN (p=0.383) on Partin Tables. Tumor volume in 75% RP was greater than 2 mL. Two patients with IDC-P only in PBx were treated with radiation and had normalized PSA after treatment.
Conclusions: IDC-P is rare (2.8%) and is even rarer (0.26%) as an isolated finding in PBx. It is strongly associated with high grade and high volume PCa. Majority of patients were managed non-surgically. The incidence of SVI is significantly higher than that predicted by Partin Tables, suggesting that IDC-P identified in PBx may provide additional prognostic information.
Category: Genitourinary (including renal tumors)
Monday, March 19, 2012 8:00 AM
Platform Session: Section A, Monday Morning