Pharmacogenetic (PGx) testing for germline variants in the DPYD and UGT1A1 genes can be used to guide fuoropyrimidine and irinotecan dosing, respectively. Despite the known association between PGx variants and chemotherapy toxicity, preemptive testing prior to chemotherapy initiation is rarely performed in routine practice. | Lau Min et al. BMC Cancer 2022 22 47 https s12885-022-09171-6 RESEARCH Open Access Preemptive pharmacogenetic testing to guide chemotherapy dosing in patients with gastrointestinal malignancies a qualitative study of barriers to implementation Kelsey S. Lau Min1 Lisa A. Varughese2 Maria N. Nelson3 Christine Cambareri4 Nandi J. Reddy5 Randall A. Oyer5 Ursina R. Teitelbaum1 and Sony Tuteja2 Abstract Background Pharmacogenetic PGx testing for germline variants in the DPYD and UGT1A1 genes can be used to guide fluoropyrimidine and irinotecan dosing respectively. Despite the known association between PGx variants and chemotherapy toxicity preemptive testing prior to chemotherapy initiation is rarely performed in routine practice. Methods We conducted a qualitative study of oncology clinicians to identify barriers to using preemptive PGx testing to guide chemotherapy dosing in patients with gastrointestinal malignancies. Each participant completed a semi-structured interview informed by the Consolidated Framework for Implementation Research CFIR . Interviews were analyzed using an inductive content analysis approach. Results Participants included sixteen medical oncologists and nine oncology pharmacists from one academic medical center and two community hospitals in Pennsylvania. Barriers to the use of preemptive PGx testing to guide chemotherapy dosing mapped to four CFIR domains intervention characteristics outer setting inner setting and characteristics of individuals. The most prominent themes included 1 a limited evidence base 2 a cumbersome and lengthy testing process and 3 a lack of insurance coverage for preemptive PGx testing. Additional barriers included clinician lack of knowledge difficulty remembering to order PGx testing for eligible patients challenges with PGx test interpretation a questionable impact of preemptive PGx testing on clinical care and a lack of alternative therapeutic options for some patients found to have actionable PGx .
