[904] Prostate Cancer Multifocality and Heterogeneity: Implications for Gleason Grading, Tumor Volume Measurement and Tissue Sampling for Research

Cheng Cheng Huang, Max Kong, Qinghu Ren, Fang-Ming Deng, Jonathan Melamed, Ming Zhou. New York University Langone Medical Center, New York, NY

Background: Prostate cancer (PCa) is well-known for its multifocality and heterogeneity in pathological characteristics. 2004 ISUP consensus recommended use “dominant tumor nodule” for grading. Tissue utilization for research also sample “dominant tumor nodule”. However, the definition of “dominant tumor nodule” is ambiguous in terms of which pathological parameter (Gleason score [GS], tumor size and extraprostatic extension [EPE]) should be used.
Design: For 104 consecutive radical prostatectomies, all tumor nodules were traced on H&E slides and transferred to a prostate map along with the detailed pathological parameters for all the tumor nodules, including GS, tumor size and EPE status.
Results: 11 (10.6%) had unifocal tumor. 93 (89.4%) had multifocal tumors with a mean number of tumor nodule 3.2 (range 2-8). EPE was present in 35 (37.6%) cases with multifocal tumors. EPE was present in tumor nodules with highest GS and largest size in 29/35 (82.9%) cases. In remaining 6 (17.1%) cases, EPE was present in a tumor nodule with a lower GS or smaller size. EPE correlated better with highest GS than largest tumor size, present in 34/35 (97.1%) nodules with highest GS and 29/35 (82.9%) nodules with largest size (p=0.047). In 58 cases with organ-confined (negative EPE) multifocal tumors, highest GS and largest size were seen in the same tumor nodules in 55 (94.8%) cases. In this series, a tumor nodules with EPE, highest GS and largest size (in cases with EPE) or highest GS and largest size (in cases without EPE) were identified in 84 (90.3%) cases, while 9 (9.7%) did not have EPE, highest GS and largest size all in the same tumor nodules.
Conclusions: Majority (89.4%) of PCas are multifocal. In these cases, a dominant tumor nodule with EPE, highest GS and largest size are identified in 90.3% cases. GS correlates better than tumor size with EPE. We suggest use EPE status first, GS second and tumor size third in assigning so-called dominant tumor nodules.
Category: Genitourinary (including renal tumors)

Monday, March 4, 2013 1:00 PM

Poster Session II # 156, Monday Afternoon

 

Close Window