ERCC, TS, RRM1, EGFR, and KRAS biomarker integration into a community-based medical oncology practice.

Abstract

6156 Background: Feasibility of routine use of biomarkers in a community setting was evaluated to determine turn-around-time (TAT), and adequacy of specimen for PCR-based analyses of ERCC,TS, RRM1, KRAS, BRAF, and EGFR. Methods: 104 consecutive patients' charts for which biomarkers were requested were reviewed from 6/26/08 to 12/31/09. TAT was defined as the number of days between the faxed order for biomarker testing and the receipt of results by the ordering physician. FFPE tissues were dissected using microdissection and analyzed EGFR, ERCC1, RRM1, and TS mRNA expression using a quantitative real-time RT-PCR. Results: Median TAT was 13 days (6-37). Tissue acquisition was the rate-limiting step, averaging 7 days. Median TAT for CRC was 12 days. PCR results could not be obtained in 57/ 397(14%) requested tests, reported as quantity not sufficient (QNS) for analysis. A QNS was reported for at least 1 requested test in 16/104 patients (15%). Histology compromised 44 Lung, 36 CRC, 24 other. Favorable results for RRM1 low (<0.97 in lung CA) were seen in 14/55 (25%), for ERCC1 low (<1.7 in Lung CA) in 7/31 (23%), for TS low (<2.33 in Lung CA) in 7/21 (33%), for TS low (<4.00 inCRC) in 18/28 (64%), and for ERCC1 low(<1.73 in CRC) in 8/27 (30%) of patients. Conclusions: The QNS rates and TAT are consistent with previously reported data from academic tertiary centers despite delays in acquiring tissue blocks and transport of samples between centers. These results demonstrate the practical feasibility of routine implementation of biomarkers into the community-practice setting. RRM1 TS ERCC1 Tests 55 77 87 QNS 13 16 16 Expression 1.76 3.65 2.92 EGF KRAS BRAF Tests 16 79 14 QNS 0 11 1 Mutation (+) 2 (13%) 13 (16%) 3 (14%) Author Disclosure Employment or Leadership Position Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Genoptix, Response Genetics Response Genetics Response Genetics