Abstract 3129: Investigating the importance of prostate tumor location and symmetry in a racially diverse, military cohort

Abstract

Abstract Introduction and objective Prostate cancer (CaP) tumor location (TL) and symmetry (TS), may help forecast CaP outcomes in radical prostatectomy (RP) patients. The study aim was to examine associations between CaP TL and TS with disease pathology and progression, including biochemical recurrence (BCR)-free survival especially whether such associations differ across race. Methods This retrospective cohort study included 1140 patients enrolled at the Walter Reed National Military Medical Center who underwent RP between 1993 and 2008. TL and TS were recorded for index tumors (i.e, largest/highest grade) in whole-mounted RP specimen sections. TLs were divided into coronal versus axial planes. For coronal plane, TL was sub-divided into anterior (A), antero-lateral (AL), lateral (L), postero-lateral (PL), posterior (P) and diffuse (D) (includes A, AL, L, PL and P). The axial plane locations included base (B), mid (M) and apex (A). Kaplan Meier (KM) estimation curves were used to model BCR-free and DM-free survival. Results Mean age at diagnosis was 59.3 years, 27.1% were African-American (AA) and 76.7% were non-symmetric (NST). According to KM analysis patients with NST experienced significantly worse BCR-free survival (p=0.003) with no racial differences found (CA: p=0.02, AA: p=0.04). Tumor location (coronal plane) distribution by race was: A and AL tumors (CA: 9.6%, 7.5% vs. AA: 9.5%, 5.5% respectively), D tumors (CA: 6.9% vs. AA: 9.4%, respectively), L tumors (CA: 9.3% vs. AA: 6.5%, respectively), P and PL tumors (CA: 21.2%, 45.6% vs. AA: 22.7%, 46.3%, respectively) (p=0.36). In the axial plane exclusively A or B tumors are rare (CA: 3.1%, 1.3% vs. AA: 2.6%, 0%, respectively) while exclusively M tumors are more frequent (CA: 27.9% vs. AA: 23%, respectively). Tumors spanning two axial location categories MA and BM tumors were (CA: 27.6%, 15.6% vs. AA: 34%, 8.4%, respectively). Tumors spanning three axial location categories BMA were (CA: 21.8% vs. AA: 30.7%, respectively) (p<.0001). No racial differences in BCR-free survival were observed for D (CA: p<.0001, AA: p=.07) or BMA (CA p<.0001; AA p=0.0004) tumors. The share of tumors with nuclear grade III in D or BMA location categories was (10.5% and 7.2%, respectively; p<.0001) while the difference in NST and ST was (4.2% vs. 0.8%, p=.0002). Conclusions In this longitudinal, racially diverse cohort of RP patients, TL and TS were informative features in predicting BCR. However, this study did not find evidence of racial differences in these associations with the exception of axial tumor location. These findings have implications for treatment stratification at time of RP. Citation Format: William Gesztes, Grant Williams, Jennifer Cullen, Allen Burke, Denise Young, Justin Mygatt, Yongmei Chen, Huai-Ching Kuo, Shiv Srivastava, Kevin Rice, Inger Rosner, Isabell Sesterhenn. Investigating the importance of prostate tumor location and symmetry in a racially diverse, military cohort [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3129.