Page 220 - Personalised medicine of fluoropyrimidines using DPYD pharmacogenetics Carin Lunenburg

Chapter 8
5-FU or capecitabine, but were not genotyped for DPYD variants (Figure 1).
Two patients, who received 5-FU or capecitabine and were genotyped, were excluded because their medical records revealed they had received 5-FU or capecitabine prior to 15 April 2013. Of the 39 patients who were genotyped without receiving 5-FU or capecitabine therapy, 33 patients eventually did not start their therapy, although there was an intention to treat at the time of requesting the screening test. Six patients started their therapy after 31 December 2014 and were therefore not identified by the search. Of the 101 patients with a 5-FU or capecitabine prescription and no DPYD-genotyping record, the medical records were screened resulting in a legitimate reason not to genotype in 60 cases (Table 2). Legitimate reasons included; any notes on prior treatment with 5-FU or capecitabine (e.g., outside LUMC) or invalid patient files (e.g., no medical dossier found for the oncology department). For 41 patients who had a prescription for newly 5-FU or capecitabine no reason was found to neglect genotyping. After data cleaning, 314 patients with a newly 5-FU or capecitabine prescription remained in the dataset and 273 of these patients were genotyped as depicted in Figure 1. The clinical acceptance of the prospective DPYD screening program is displayed
as percentage per month in Figure 2. The average clinical acceptance was 86.9%.
Figure 1. Patient selection
Flowchart following the results from the two searches. Patients could be both genotyped and prescribed 5-FU or capecitabine, or only genotyped, or only prescribed 5-FU or capecitabine. If the intention to treat was present, patients should have been genotyped and these patients are ‘eligible for evaluation’.
a These two patients were excluded because their medical records revealed they had received 5-FU or capecitabine prior to April 15th 2013;
b Legitimate reasons were: e.g., any notes on prior treatment with 5-FU or capecitabine (e.g., outside LUMC) or invalid patient files (e.g., no medical dossier found for the oncology department). Abbreviations: 5-FU: 5-fluorouracil, CAP: capecitabine.
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