Screening For Dihydropyrimidine Dehydrogenase Deficiency Research Articles

DPD deficiency in an Irish oncology centre: Prevalence and clinical implications.

Fluorouracil (5FU) and capecitabine are metabolised by dihydropyrimidine dehydrogenase (DPD). Up to 9% of people have low levels of a working DPD enzyme and are at risk of severe toxicity from 5FU/capecitabine. In April 2020, the EMEA recommended patients undergo prospective screening for DPD deficiency before starting treatment, and this was introduced in our hospital. We retrospectively reviewed records of all patients receiving 5FU/capecitabine in a tertiary Irish cancer centre from May 2020 to April 2021 (n = 197), and those starting first-line treatment in May 2019-April 2020 (n = 97). Our primary outcome was to estimate the prevalence of DPYD variant genes by prospective genotypic screening, with secondary outcomes including variant prevalence by prospective and reactive screening in patients receiving first-line treatment, and 5FU toxicity/tolerability in those with detected variants. In those treated 2020-2021, cancer subtypes included colorectal (n = 120, 61%), breast (n = 34, 17%), and biliary/pancreatic cancers (n = 21, 11%). Median patient age was 62 (range 25-86 years); 40% (n = 79) of patients were screened overall, with a prospective-screening deficiency prevalence of 6.8% (n = 3 of 44). Three patients had pathogenic DPYD-variants detected by prospective screening and tolerated treatment with 50% up-front dose reduction of 5FU, two had variants of uncertain significance detected by reactive screening. Other Irish studies estimated prevalence at 11-12%. As the number of variants detected was small, and screening rates were incomplete, our study may have underestimated prevalence. Approximately 6.8% of Irish patients may carry DPD deficiencies, prospective screening is essential to reduce the risk of life-threatening toxicity in these patients.

Screening for dihydropyrimidine dehydrogenase deficiency by measuring uracilemia in chronic kidney disease patients is associated with a high rate of false positives

BackgroundPretherapeutic screening for dihydropyrimidine dehydrogenase (DPD) deficiency based on the measurement of plasma uracil ([U]) is recommended prior to the administration of fluoropyrimidine-based chemotherapy. Cancer patients frequently have impaired kidney function, but the extent to which kidney function decline impacts [U] levels has not been comprehensively investigated. MethodsWe assessed the relationship between DPD phenotypes and estimated glomerular filtration rate (eGFR) in 1751 patients who benefited on the same day from a screening for DPD deficiency by measuring [U] and [UH2]:[U], and an evaluation of eGFR. The impact of a kidney function decline on [U] levels and [UH2]:[U] ratio was evaluated. ResultsWe observed that [U] was negatively correlated with eGFR, indicating that [U] levels increase as eGFR declines. For each ml/min of eGFR decrease, [U] value increased in average by 0.035 ng/ml. Using the KDIGO classification of chronic kidney disease (CKD), we observed that [U] values >16 ng/ml (DPD deficiency) were measured in 3.6 % and 4.4 % of stage 1 and 2 CKD (normal-high eGFR, >60 ml/min/1.73 m2) patients, but in 6.7 % of stage 3A CKD patients (45 to 59 ml/min/1.73 m2), 25% of stage 3B CKD patients (30 to 44 ml/min/1.73 m2), 22.7% of stage 4 CKD patients (15 to 29 ml/min/1.73 m2 and 26.7% of stage 5 CKD patients (<15 ml/min/1.73 m2). [UH2]:[U] ratios were not impacted by kidney function. ConclusionDPD phenotyping based on the measurement of plasma [U] in patients with decreased eGFR is associated with an exceedingly high rate of false positives when kidney function decline reaches 45 ml/minute/1.73 m2 of eGFR or lower. In this population, an alternative strategy that remain to be evaluated would be to measure the [UH2]:[U] ratio in addition to [U].

Impact of Guidelines Regarding Dihydropyrimidine Dehydrogenase (DPD) Deficiency Screening Using Uracil-Based Phenotyping on the Reduction of Severe Side Effect of 5-Fluorouracil-Based Chemotherapy: A Propension Score Analysis.

Dihydropyrimidine dehydrogenase (DPD) deficiency is associated with severe fluoropyrimidines-induced toxicity. As of September 2018, French recommendations call for screening for DPD deficiency by plasma uracil quantification prior to all fluoropyrimidine-based chemotherapy. A dose reduction of fluoropyrimidine is recommended when uracil concentration is equal to or greater than 16 ng/mL. This matched retrospective study assessed the impact of DPD screening on the reduction of severe side effects and on the management of DPD-deficient patients. Using a propensity score, we balanced the factors influencing 5-Fluorouracil (5-FU) toxicity. Then, the severity scores (G3 and G4 severity as well as their frequency) of patients who did not benefit from DPD screening were compared with those of patients who benefited from DPD screening for each treatment cycle (from 1 to 4). Among 349 screened patients, 198 treated patients were included. Among them, 31 (15.7%) had DPD deficiency (median uracilemia 19.8 ng/mL (range: 16.1–172.3)). The median toxicity severity score was higher in the unscreened group for each treatment cycle (0 vs. 1, p < 0.001 at each cycle from 1 to 4) as well as the cumulative score during all courses of treatment (p = 0.028). DPD-deficient patients received a significantly lower dose of 5-FU (p < 0.001). This study suggests that pretherapeutic plasmatic uracil assessment, along with 5-FU dosage adjustment, may be beneficial in reducing 5-FU toxicity in real-life patients.

70P Fluoropyrimidine (FP) dose individualization based on pretreatment uracil levels: Safety and pharmacokinetic (PK) analysis from the Alpe2U study

Risk of severe adverse events (AEs) during FP treatment can be significantly reduced through dose reduction in patients (pts) with dihydropyrimidine dehydrogenase (DPD) deficiency, the main FP metabolizing enzyme. Hence, in 2020 EMA stated that screening for DPD deficiency should be performed before FP treatment by DPYD genotyping, or by DPD phenotyping using plasma uracil (U) levels. Based on previous studies, pts with U >16 ng/ml are considered DPD deficient. However, a specific dosing strategy for these pts is missing.

Determination of plasma uracil as a screening for dihydropyrimidine dehydrogenase deficiency: clinical application in oncological treatments

AimsTreatment with dihydropyrimidines poses a significant risk of serious adverse reactions for patients with dihydropyrimidine dehydrogenase (DPD) deficiency. This study seeks to analyse the correlation between DPD deficiency and plasmatic...

P-297 Upfront dihydropyrimidine dehydrogenase deficiency detection to secure 5-FU or capecitabine administration: Application to colorectal cancer patients

Fluorouracil (5-FU) is rapidly degraded by dihydropyrimidine dehydrogenase (DPD). Therefore, a DPD deficiency can lead to severe toxicity or even death after treatment with 5-FU or capecitabine. Various tests based on the evaluation of the DPD enzymatic activity have been studied for screening for DPD deficiency in order to avoid this toxicity. Testing includes phenotyping (direct or indirect measurement of enzyme activity) or genotyping (detection of inactivating polymorphisms) of the DPD gene.

Cost effectiveness of DPYD genotyping to screen for dihydropyrimidine dehydrogenase (DPD) deficiency prior to adjuvant chemotherapy for colon cancer.

55 Background: Fluoropyrimidine chemotherapy agents, including 5-fluorouracil and capecitabine, are the backbone of adjuvant treatment for colon cancer, and adjuvant chemotherapy substantially reduces recurrence and mortality after surgical resection of stage 3 colon cancer. While fluoropyrimidine chemotherapy is generally safe, the risk of severe, potentially fatal chemotherapy toxicity is substantially increased for the 2-3% of U.S. patients with DPD deficiency caused by pathogenic variants in the DPYD gene. DPYD genotype testing is readily available in the U.S. but has not been widely adopted. We evaluated the cost effectiveness of DPYD genotyping prior to adjuvant chemotherapy for colon cancer in the U.S. Methods: We constructed a Markov model to simulate screening for DPD deficiency with DPYD genotyping (versus no screening) among patients receiving fluoropyrimidine-based adjuvant chemotherapy for stage 3 colon cancer. Screen-positive patients were modeled to receive dose-reduced fluoropyrimidine chemotherapy. Model transition probabilities for treatment-related toxicities were derived from published clinical trial data with annotation of DPYD genotype and chemotherapy dosing strategy. Our analysis is from the healthcare perspective, with a time horizon of five years and an annual discount rate of 3% for future costs and benefits. Direct healthcare costs and health utilities were estimated from published sources and converted to 2020 US dollars, and post-treatment survival was modeled from SEER data. The primary outcome was the incremental cost-effectiveness ratio (ICER), defined as dollars per quality-adjusted life year (QALY). We used a value of $100,000/QALY as the cost-effectiveness threshold. One-way sensitivity analyses were used to examine model uncertainty. Results: Compared with no screening, screening for DPD deficiency with DPYD genotyping increased per-patient costs by $106 and improved quality-adjusted survival by 0.0028 QALYs, leading to an ICER of $37,300/QALY. In one-way sensitivity analyses, the ICER exceeded $100,000/QALY when the carrier frequency of pathogenic DPYD gene variants was less than 1.17%, and when the specificity of DPYD genotyping was less than 98.9%. Cost-effectiveness estimates were not sensitive to the cost of DPYD genotyping, the cost of toxicity-related hospitalizations, or the health utility associated with grade 3-4 toxicity. Conclusions: Among patients receiving adjuvant chemotherapy for stage 3 colon cancer, screening for DPD deficiency with DPYD genotyping is a cost-effective strategy for preventing infrequent but severe, sometimes fatal toxicities of fluoropyrimidine chemotherapy.

Joint Belgian recommendation on screening for DPD-deficiency in patients treated with 5-FU, capecitabine (and tegafur)

ABSTRACT Objectives Fluoropyrimidines such as 5-Fluorouracil (5-FU), capecitabine and tegafur are drugs that are often used in the treatment of maliginancies. The enzyme dihydropyrimidine dehydrogenase (DPD) is the first and rate limiting enzyme of 5-FU catabolism. Genetic variations within the DPYD gene (encoding for DPD protein) can lead to reduced or absent DPD activity. Treatment of DPD deficient patients with fluoropyrimidines can result in severe and, rarely, fatal toxicity. Screening for DPD deficiency should be implemented in practice. Methods The available methods in routine to screen for DPD deficiency were analyzed and discussed in several group meetings involving members of the oncological, genetic and toxicological societies in Belgium: targeted genotyping based on the detection of 4 DPYD variants and phenotyping, through the measurement of uracil and dihydrouracil/uracil ratio in plasma samples. Results The main advantage of targeted genotyping is the existence of prospectively validated genotype-based dosing guidelines. The main limitations of this approach are the relatively low sensitivity to detect total and partial DPD deficiency and the fact that this approach has only been validated in Caucasians so far. Phenotyping has a better sensitivity to detect total and partial DPD deficiency when performed in the correct analytical conditions and is not dependent on the ethnic origin of the patient. Conclusion In Belgium, we recommend phenotype or targeted genotype testing for DPD deficiency before starting 5-FU, capecitabine or tegafur. We strongly suggest a stepwise approach using phenotype testing upfront because of the higher sensitivity and the lower cost to society.

Dihydropyrimidine Dehydrogenase Deficiency: To Screen or Not to Screen?

5-fluorouracil (5-FU) and its prodrug capecitabine are frequently prescribed in oncology. While usually well tolerated, toxicity can be severe, and even life-threatening. A dihydropyrimidine dehydrogenase (DPD) deficiency can cause severe toxicity. Current testing for DPD deficiency does not meet the criteria for a routine screening test prior to 5-FU therapy. A case study of a fatality secondary to capecitabine toxicity is reviewed and literature is examined regarding general screening for DPD deficiency.

Dihydropyrimidine dehydrogenase deficiency in patients with severe toxicity after 5-fluorouracil: a retrospective single-center study.

Background5-Fluorouracil (5-FU) is an agent frequently used in the treatment of solid cancers. A deficiency in the enzyme that catabolizes 5-FU leads to severe toxicity. The gene responsible for this enzyme is DPYD, located on chromosome 1q22. The most prevalent alteration described is DPYD*2A, which leads to a splicing defect and thus skipping of the translation of an entire exon. The objectives of this retrospective study were to describe the frequencies of DPYD gene mutations in a Belgian population and to correlate them with the grade of toxicity.MethodsThis was a retrospective, single-center study conducted at the University Hospitals Leuven, by reviewing a database of patients screened for DPYD gene mutations between May 2009 and June 2015 after prolonged grade 3-4 toxicity. Polymerase chain reaction sequencing of exons 2, 6, 10, 11, 13, 18, 19 and 22, and pyrosequencing of exon 14 were performed by an in-house laboratory.ResultsOf the 80 patients screened, 65 were heterozygous or compound heterozygous for DPYD and 3 had a homozygous mutation. The most prevalent mutation in our population was DPYD*9A.ConclusionsDespite previous reports, in our small retrospective study the most prevalent variation in patients with severe adverse events was DPYD*9A. As this variant has previously been reported to be benign, we suggest that screening for dihydropyrimidine dehydrogenase deficiency should be extended across multiple exons of the DPYD gene.

DPYD and Fluorouracil-Based Chemotherapy: Mini Review and Case Report.

5-Fluorouracil remains a foundational component of chemotherapy for solid tumour malignancies. While considered a generally safe and effective chemotherapeutic, 5-fluorouracil has demonstrated severe adverse event rates of up to 30%. Understanding the pharmacokinetics of 5-fluorouracil can improve the precision medicine approaches to this therapy. A single enzyme, dihydropyrimidine dehydrogenase (DPD), mediates 80% of 5-fluorouracil elimination, through hepatic metabolism. Importantly, it has been known for over 30-years that adverse events during 5-fluorouracil therapy are linked to high systemic exposure, and to those patients who exhibit DPD deficiency. To date, pre-treatment screening for DPD deficiency in patients with planned 5-fluorouracil-based therapy is not a standard of care. Here we provide a focused review of 5-fluorouracil metabolism, and the efforts to improve predictive dosing through screening for DPD deficiency. We also outline the history of key discoveries relating to DPD deficiency and include relevant information on the potential benefit of therapeutic drug monitoring of 5-fluorouracil. Finally, we present a brief case report that highlights a limitation of pharmacogenetics, where we carried out therapeutic drug monitoring of 5-fluorouracil in an orthotopic liver transplant recipient. This case supports the development of robust multimodality precision medicine services, capable of accommodating complex clinical dilemmas.

Prevention of 5-fluorouracil-induced early severe toxicity by pre-therapeutic dihydropyrimidine dehydrogenase deficiency screening: Assessment of a multiparametric approach

5-Fluorouracil (5-FU)–based treatments can lead to early-onset severe (4%–5%) even fatal (0.3%) toxicities in patients with dihydropyrimidine dehydrogenase (DPD) deficiency. This multicenter prospective cohort study aimed to assess the clinical benefit of pretherapeutic screening for DPD deficiency using a multiparametric approach. Two parallel cohorts of patients treated with 5-FU–based chemotherapy for colorectal carcinoma were compared in a prospective nonrandomized study. In arm A, patients had DPD deficiency screening before treatment, whereas in arm B no pretherapy screening was performed. Dosing was based on 5-FU administration guidelines of each institution. DPD deficiency screening was performed using a combined multiparametric approach (5-FUODPM Tox). The frequency of early grade 4–5 toxic events potentially induced by 5-FU was compared in the two groups. At total of 1,142 patients (n = 1,116 evaluable) were enrolled. In arm A, out of 718 evaluable patients, nine grade 4 early toxicities potentially related to 5-FU were reported in nine patients (1.2%) with no toxic death despite one complete DPD deficiency and 24 partial deficiencies. The 24 patients with partial deficiency had safe pharmacokinetics (PK)-monitored 5-FU. In arm B, among 398 evaluable patients, 17 grade 4–5 toxic early events potentially related to 5-FU were reported in 12 patients (4.2%). The incidence of early severe toxicity was significantly higher in arm B (P = .0019), confirming the positive impact of pretherapeutic DPD assessment. The percent of patients with a toxicity grade 3 or higher observed in arm A was 10.8% (n = 78) compared to 17.55% (n = 69) in arm B (P = .0497). The percentage of death was reduced from 2.5/1,000 in arm B to 0 in arm A. The time to occurrence of all grade ≥3 toxicities was determined in both arms and the difference between the two arms was significant (P = .047). Overall, one patient with complete DPD deficiency confirmed retrospectively died within 13 days from grade 5 multivisceral toxicity. Enrollment was prematurely closed after external experts’ decision. In conclusion, multiparametric pretherapeutic DPD deficiency screening significantly lowered the risk of early severe toxicity and avoided an early toxic death. This approach should be used for safe administration of 5-FU–based treatments.

The role of pharmacogenetics in the new ESMO colorectal cancer guidelines.

The role of pharmacogenetics in the new ESMO colorectal cancer guidelines.

Severe fluoropyrimidine toxicity due to novel and rare DPYD missense mutations, deletion and genomic amplification affecting DPD activity and mRNA splicing

Dihydropyrimidine dehydrogenase (DPD) is the initial and rate-limiting enzyme in the catabolism of 5-fluorouracil (5FU). Genetic variations in DPD have emerged as predictive risk factors for severe fluoropyrimidine toxicity. Here, we report novel and rare genetic variants underlying DPD deficiency in 9 cancer patients presenting with severe fluoropyrimidine-associated toxicity. All patients possessed a strongly reduced DPD activity, ranging from 9 to 53% of controls. Analysis of the DPD gene (DPYD) showed the presence of 21 variable sites including 4 novel and 4 very rare aberrations: 3 missense mutations, 2 splice-site mutations, 1 intronic mutation, a deletion of 21 nucleotides and a genomic amplification of exons 9–12. Two novel/rare variants (c.2843T>C, c.321+1G>A) were present in multiple, unrelated patients. Functional analysis of recombinantly-expressed DPD mutants carrying the p.I948T and p.G284V mutation showed residual DPD activities of 30% and 0.5%, respectively. Analysis of a DPD homology model indicated that the p.I948T and p.G284V mutations may affect electron transfer and the binding of FAD, respectively. cDNA analysis showed that the c.321+1G>A mutation in DPYD leads to skipping of exon 4 immediately upstream of the mutated splice-donor site in the process of DPD pre-mRNA splicing. A lethal toxicity in two DPD patients suggests that fluoropyrimidines combined with other therapies such as radiotherapy might be particularly toxic for DPD deficient patients. Our study advocates a more comprehensive genotyping approach combined with phenotyping strategies for upfront screening for DPD deficiency to ensure the safe administration of fluoropyrimidines.

Dihydro pyrimidine dehydrogenase deficiency in patients treated with capecitabine based regimens: a tertiary care centre experience.

Dihydropyrimidine dehydrogenase (DPD) enzyme is the rate limiting step in the metabolism of capecitabine, and its deficiency leads to severe toxicities and rarely, death. A total of 506 patients were treated in the GI Medical Oncology unit of our institution with capecitabine containing regimens with a dose range of 1,250 to 2,000 mg/m(2)/day during the period from June 2013 to June 2015. Patients with grade (Gr) 3/4 toxicities requiring in-patient care (life threatening complications) were planned for DPD activity testing by peripheral blood PCR sequencing. Thirty-one patients developed Gr 3/4 toxicities during cycle 1 of capecitabine. This included mucositis in 24 (77%), diarrhea in 29 (94%), hand-foot syndrome (HFS) in 13 (42%) and myelosuppression in 5 (16%) patients. Twenty-two (81.4%) were found to be DPD deficient with 6 patients negative for DPD mutation. Three patients did not undergo the DPD analysis as advised. More than one mutation was seen in 11 patients. The relative frequencies of the mutations were IVS14+1G→A in 39%, with 13% having homozygosity, 85 T→C in 36%, 1627 A→G in 32%, 496 A→G in 18% and 2194 G→A in 18%, respectively. After dose reduction in cycle 2 in 17 patients of the DPD mutation positive cohort, statistically significant reduction in the toxicities was seen. Dose reduction in DPD deficient patients, reduces risk of life threatening complications significantly but not completely. Upfront screening for DPD deficiency in Indian patients should be evaluated further in view of potentially high homozygous DPD mutation prevalence.

Erratum: Evaluation of predictive tests for screening for dihydropyrimidine dehydrogenase deficiency

Erratum: Evaluation of predictive tests for screening for dihydropyrimidine dehydrogenase deficiency

Sensitivity and specificity of an oral uracil-loading test dose for screening for DPD deficiency.

11101 Background: 5-fluorouracil (5FU) and capecitabine (CAP) are extensively metabolised by dihydropyrimidine dehydrogenase (DPD). DPD deficiency can lead to severe toxicity after 5FU or CAP. Urac...

Evaluation of predictive tests for screening for dihydropyrimidine dehydrogenase deficiency

5-Fluorouracil (5-FU) is rapidly degraded by dihyropyrimidine dehydrogenase (DPD). Therefore, DPD deficiency can lead to severe toxicity or even death following treatment with 5-FU or capecitabine. Different tests based on assessing DPD enzyme activity, genetic variants in DPYD and mRNA variants have been studied for screening for DPD deficiency, but none of these are implemented broadly into clinical practice. We give an overview of the tests that can be used to detect DPD deficiency and discuss the advantages and disadvantages of these tests.

A mild phenotype of dihydropyrimidine dehydrogenase deficiency and developmental retardation associated with a missense mutation affecting cofactor binding

Objectives Evaluation of a non-synonymous mutation associated with dihydropyrimidine dehydrogenase (DPD) deficiency. Design and methods DPD enzyme analysis, mutation analysis and molecular dynamics simulations based on the 3D-model of DPD. Results The substitution Lys63Glu is likely to affect the FAD binding pocket within the DPD protein and contributes to a near-complete DPD deficiency in a patient with developmental retardation. Conclusions Like other DPD variants attenuating FAD binding, Lys63Glu should be included in screening for DPD deficiency.

Intragenic deletions and a deep intronic mutation affecting pre-mRNA splicing in the dihydropyrimidine dehydrogenase gene as novel mechanisms causing 5-fluorouracil toxicity

Dihydropyrimidine dehydrogenase (DPD) is the initial enzyme acting in the catabolism of the widely used antineoplastic agent 5-fluorouracil (5FU). DPD deficiency is known to cause a potentially lethal toxicity following administration of 5FU. Here, we report novel genetic mechanisms underlying DPD deficiency in patients presenting with grade III/IV 5FU-associated toxicity. In one patient a genomic DPYD deletion of exons 21–23 was observed. In five patients a deep intronic mutation c.1129–5923C>G was identified creating a cryptic splice donor site. As a consequence, a 44 bp fragment corresponding to nucleotides c.1129–5967 to c.1129–5924 of intron 10 was inserted in the mature DPD mRNA. The deleterious c.1129–5923C>G mutation proved to be in cis with three intronic polymorphisms (c.483 + 18G>A, c.959–51T>G, c.680 + 139G>A) and the synonymous mutation c.1236G>A of a previously identified haplotype. Retrospective analysis of 203 cancer patients showed that the c.1129–5923C>G mutation was significantly enriched in patients with severe 5FU-associated toxicity (9.1%) compared to patients without toxicity (2.2%). In addition, a high prevalence was observed for the c.1129–5923C>G mutation in the normal Dutch (2.6%) and German (3.3%) population. Our study demonstrates that a genomic deletion affecting DPYD and a deep intronic mutation affecting pre-mRNA splicing can cause severe 5FU-associated toxicity. We conclude that screening for DPD deficiency should include a search for genomic rearrangements and aberrant splicing.Electronic supplementary materialThe online version of this article (doi:10.1007/s00439-010-0879-3) contains supplementary material, which is available to authorized users.