Abstract 4529: Effect of preanalytic variables on established and emerging thrombosis-related biomarkers in an ethnically and racially diverse population of cancer patients and healthy subjects at a safety net hospital

Abstract

Abstract The link between cancer and thrombosis, especially venous thromboembolism, is well established and thrombotic risk is exacerbated by cancer treatments, such as surgery and chemotherapy. This ongoing study aims to determine the impact of pre-analytic variables (PAVs) on thrombosis biomarkers in a diverse cancer patient and non-cancer subject population at an urban safety net hospital. Citrated blood from newly diagnosed, treatment-naïve patients of 11 cancer types or from non-cancer controls was processed to examine these variables: time to fractionation (2 and 4 hrs), plasma freeze-thaw cycles (2 and 3 cycles), and plasma delay to testing (24 or 72 hrs at 4oC). Regular processing (< 1 hour to centrifuge or 1 freeze-thaw cycle) served as the control sample for the variables. Current interim data presents biomarker data for D-dimer (DDE), Factor VIII activity (FVIII), soluble P-selectin (sP-Sel), prothrombin fragment 1+2 (F1+2), plasma DNA (DNA) and myeloperoxidase (MPO). Assays are performed in the hospital clinical lab (DDE, FVIII) or in our research lab following 30 detailed standard operating procedures (SOPs). Cancer patient demographics are 60% male, 40% Black/African-American, 38% Caucasian, 18% Hispanic, 3% Native American, and 1% Asian with an age range of 38-86 years. Non-cancer controls are 52% male, 59% Caucasian, 15% Black/African-American, 19% Asian, and 7% Hispanic with an age range of 23-64 years. Interim project data shows increased thrombosis biomarker levels in cancer subjects, except for sP-Sel and F1+2. Biomarker levels in cancer patients (n=9-52) were increased by approximately 300ng/ml DNA, 100ng/ml DDE, and 5ng/mL MPO with a trending increase in FVIII (~30%) when compared to non-cancer controls (n=17-22). Freeze-thaw of plasma had no effect, while a 2hr time to fractionation resulted in significantly increased MPO (~10ng/mL), FVIII (~14%) and F1+2 (~310 pg/mL). Delay to testing done for DNA and DDE showed with no apparent effect on biomarker levels after 24 or 72 hrs at 4oC. Current data show biomarker levels are impacted by presence of cancer rather than ethnicity of the patient. Donor recruitment is ongoing with shifting strategies to meet recruitment goals of non-cancer donors for greater diversity and older age to more closely reflect our cancer patient population. Rigorous control of sample handling and assay performance using SOPs that are compatible with a hospital setting contribute to identifying PAVs that matter for design of generalizable procedures. Citation Format: Morgan P. Thompson, Elizabeth R. Duffy, DJ Stearns-Kurosawa, Jasmin Bavarva, Shinichiro Kurosawa, Jiyoun Kim, Cheryl Spencer, Daniel Remick, Mark Sloan, Joel Henderson, Kerrie P. Nelson, Joseph Y. Tashjian, Yibing Wei, Rachana Agarwal, Michelle A. Berny-Lang, Chris Andry. Effect of preanalytic variables on established and emerging thrombosis-related biomarkers in an ethnically and racially diverse population of cancer patients and healthy subjects at a safety net hospital [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4529.