191P - Novel approach to proficiency testing demonstrates wide gaps in biomarker quality for colon cancer treatment

Background

Biomarkers are fundamental to oncology, closely tying this practice to that of laboratory medicine. Results are required to be accurate, timely, comprehensive, and comprehendible. External proficiency testing is a key tool in maintaining quality. Traditional schemes test analytic accuracy. Here, we demonstrate the feasibility and utility of a novel end-to-end proficiency testing exercise examining the entire process of biomarker testing.

Methods

Challenge specimens were made using resected colon cancer tissue, each paired with a clinical vignette and distributed to participating labs. Participants were asked to provide all molecular testing required, which could include pre-analytic preparation, immunohistochemistry, gene sequencing, or other methodologies, and to draft and return a final report for each case upon completion. Reports were redistributed to an assessor team including oncologists, who chose therapy based on each lab’s biomarker report. Finally, participants were graded based on their ability to guide oncologists to the most appropriate treatment. Gold standard treatments for each case were decided by assessors prior to the exercise, based on reference results and clinical vignettes.

Results

Eight laboratories participated. Three laboratories were found to have suboptimal results, two leading oncologists to incorrect therapeutic prescriptions (Table) and one withdrawn. Turnaround time ranged from 6-86 days (median 24).

Table: 191P

Resulting number of medical oncologist assessors prescribing the optimal treatment choice based on reported results

Conclusions

This is the first report of end-to-end proficiency testing, providing valuable insights into biomarker quality beyond analytic accuracy, including specimen management, communication, and turnaround time. Here, significant quality gaps were identified, generating opportunities for improvement. This paradigm shift in quality assurance to focus on the complete specimen journey is a promising tool in assessing and improving modern cancer care.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Canadian Pathology Quality Assurance - Assurance qualité canadienne en pathologie (CPQA-AQCP).

Funding

Canadian Pathology Quality Assurance - Assurance Qualité en Pathologie Canadienne (CPQA-AQPC) with funding from Pfizer.

Disclosure

M.D. Carter: Financial Interests, Personal and Institutional, Other, Honoraria: Amgen, Bayer, Merck, Novartis, Pfizer, Incyte. S. Dudani: Financial Interests, Personal and Institutional, Advisory Board: Bristol Myers Squibb, Eisai, Ipsen, Merck, Pfizer, Taiho; Financial Interests, Personal and Institutional, Other, Honoraria: AstraZeneca, Ipsen, Merck, Pfizer. J.M. Loree: Financial Interests, Personal and Institutional, Other, Consulting: Ipsen, Novartis, Amgen, SAGA Diagnostics, Taiho; Financial Interests, Personal and Institutional, Research Grant: Foundation Medicine, Amgen, Ipsen, Personalis. S. Snow: Financial Interests, Personal and Institutional, Other, Advisory Boards/Consulting: Amgen, Bayer, BeiGene, Boehringer Ingelheim, Astellas, AstraZeneca, BMS, Janssen, Knight, Lilly, Merck, MSD, Novartis, Pfizer, Roche, Sanofi, Taiho, Takeda; Financial Interests, Personal and Institutional, Member of Board of Directors: Lung Cancer Canada; Financial Interests, Institutional, Other, Research Trials (Institutional Funding): Amgen, AstraZeneca, BMS, Merck, Novartis, Sanofi. S. Yip: Financial Interests, Personal and Institutional, Advisory Board: Amgen, AstraZeneca, Bayer, Incyte, Pfizer, Roche. B.S. Sheffield: Financial Interests, Personal and Institutional, Other, Consulting/Advisory Boards/Honoraria/Research Support: Amgen, AstraZeneca, Bayer, Biocartis, Boehringer Ingelheim, Cell Marque, Elevation Oncology, Eli Lily, EMD Serono, Incyte, Janssen, Merck, Novartis, Pfizer, Roche, ThermoFisher, Turning Point Therapeutics. All other authors have declared no conflicts of interest.