Evaluation of Genomic Applications in Practice and Prevention (EGAPP) Working Group. Recommendations from the EGAPP Working Group: can UGT1A1 genotyping reduce morbidity and mortality in patients with metastatic colorectal cancer treated with irinotecan?

Chemotherapy-related hyperbilirubinemia in pediatric acute lymphoblastic leukemia: a genome-wide association study from the AIEOP-BFM ALL study group

BACKGROUND

Characterization of clinical phenotypes in context with tumor and host genomic information can aid in the development of more effective and less toxic risk-adapted and targeted treatment strategies. To analyze the impact of therapy-related hyperbilirubinemia on treatment outcome and to identify contributing genetic risk factors of this well-recognized adverse effect we evaluated serum bilirubin levels in 1547 pediatric patients with acute lymphoblastic leukemia (ALL) and conducted a genome-wide association study (GWAS).

PATIENTS AND METHODS

Patients were treated in multicenter trial AIEOP-BFM ALL 2000 for pediatric ALL. Bilirubin toxicity was graded 0 to 4 according to the Common Toxicity Criteria (CTC) of the National Cancer Institute. In the GWAS discovery cohort, including 650 of the 1547 individuals, genotype frequencies of 745,895 single nucleotide variants were compared between 435 patients with hyperbilirubinemia (CTC grades 1-4) during induction/consolidation treatment and 215 patients without it (grade 0). Replication analyses included 224 patients from the same trial.

RESULTS

Compared to patients with no (grade 0) or moderate hyperbilirubinemia (grades 1-2) during induction/consolidation, patients with grades 3-4 had a poorer 5-year event free survival (76.6 ± 3% versus 87.7 ± 1% for grades 1-2, P = 0.003; 85.2 ± 2% for grade 0, P < 0.001) and a higher cumulative incidence of relapse (15.6 ± 3% versus 9.0 ± 1% for grades 1-2, P = 0.08; 11.1 ± 1% for grade 0, P = 0.007). GWAS identified a strong association of the rs6744284 variant T allele in the UGT1A gene cluster with risk of hyperbilirubinemia (allelic odds ratio (OR) = 2.1, P = 7 × 10^- 8). TT-homozygotes had a 6.5-fold increased risk of hyperbilirubinemia (grades 1-4; 95% confidence interval (CI) = 2.9-14.6, P = 7 × 10^- 6) and a 16.4-fold higher risk of grade 3-4 hyperbilirubinemia (95% CI 6.1-43.8, P = 2 × 10^- 8). Replication analyses confirmed these associations with joint analysis yielding genome-wide significance (allelic OR = 2.1, P = 6 × 10^- 11; 95% CI 1.7-2.7). Moreover, rs6744284 genotypes were strongly linked to the Gilbert's syndrome-associated UGT1A1*28/*37 allele (r² = 0.70), providing functional support for study findings. Of clinical importance, the rs6744284 TT genotype counterbalanced the adverse prognostic impact of high hyperbilirubinemia on therapy outcome.

CONCLUSIONS

Chemotherapy-related hyperbilirubinemia is a prognostic factor for treatment outcome in pediatric ALL and genetic variation in UGT1A aids in predicting the clinical impact of hyperbilirubinemia.

TRIAL REGISTRATION

http://www.

CLINICALTRIALS

gov ; #NCT00430118.

Irinotecan dose reduction in metastatic colorectal cancer patients with homozygous UGT1A1*28 polymorphism: a single-center case series

OBJECTIVE

The UGT1A1*28 polymorphism reduces UGT1A1 enzymatic activity, which may increase the risk of severe toxicity in patients who receive standard-dose irinotecan, such as severe neutropenia and diarrhea. This real-world study assessed the optimal irinotecan dose in terms of efficacy and toxicity in metastatic colorectal cancer (mCRC) patients homozygous for the UGT1A1*28 polymorphism and receiving FOLFIRI plus bevacizumab or cetuximab as first-line therapy.

METHODS

We analyzed toxicity and treatment outcomes in seven mCRC patients who were homozygous for UGT1A1*28 and received FOLFIRI plus bevacizumab or cetuximab, with an initial irinotecan dose of 120 mg/m2.

RESULTS

Six of the seven patients tolerated 120 mg/m2 irinotecan without requiring dose reductions in subsequent cycles. The overall response and disease control rates were 43.0% (3/7) and 71.4% (5/7), respectively. The median progression-free survival and overall survival were 11.0 and 33.0 months, respectively. Only one severe adverse event, grade III neutropenia (2.5%), was observed.

CONCLUSIONS

mCRC patients homozygous for the UGT1A1*28 allele can tolerate irinotecan at an initial dose of 120 mg/m2 with favorable oncological outcomes and toxicity profiles. Further prospective studies are warranted to optimize irinotecan-based chemotherapy in these patients.

Comparison of UGT1A1 Polymorphism as Guidance of Irinotecan Dose Escalation in RAS Wild-Type Metastatic Colorectal Cancer Patients Treated With Cetuximab or Bevacizumab Plus FOLFIRI as the First-Line Therapy

Uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) polymorphism plays a crucial role in the increased susceptibility and toxicity of patients to irinotecan. This retrospective, observational study compared the clinical outcomes and adverse events (AEs) in RAS wild-type metastatic colorectal cancer (mCRC) patients treated with cetuximab or bevacizumab plus FOLFIRI with UGT1A1 genotyping and irinotecan dose escalation as the first-line therapy. In total, 173 patients with mCRC with RAS wild-type were enrolled. Among them, 98 patients were treated with cetuximab, whereas 75 patients were treated with bevacizumab. All patients received irinotecan dose escalation based on UGT1A1 genotyping. We compared the progression-free survival (PFS), overall survival (OS), objective response rates (ORRs), disease control rates (DCRs), metastatectomy, and severe adverse events (SAEs) between the two groups. The clinical effects of primary tumor sidedness and target therapy crossover were further analyzed. Over a median follow-up of 23.0 months [interquartile range (IQR), 15.032.5 months], no significant differences were observed between the cetuximab and bevacizumab groups in PFS [18.0 months vs. 14.0 months; 95% confidence interval (CI), 0.5171.027; hazard ratio (HR), 0.729; p=0.071], OS (40.0 months vs. 30.0 months; 95% CI, 0.4101.008; HR, 0.643; p=0.054), ORR (65.3% vs. 62.7%; p=0.720), DCR (92.8% vs. 86.7%; p=0.175), metastatectomy (36.7% vs. 29.3%; p=0.307), and SAEs (p=0.685). Regardless of primary tumor sidedness and target therapy crossover, no significant differences were noted in efficacy and safety between the two groups (all p>0.05). Our results revealed that patients with wild-type RAS mCRC, regardless of biologics, with UGT1A1 genotyping can tolerate escalated doses of irinotecan and potentially achieve a more favorable clinical outcome without significantly increased toxicity.

Impact of UGT1A1 Polymorphisms on Febrile Neutropenia in Pancreatic Cancer Patients Receiving FOLFIRINOX: A Single-Center Cohort Study

FOLFIRINOX (oxaliplatin, leucovorin, irinotecan, and 5-fluorouracil) is a first-line chemotherapy for metastatic pancreatic cancer (PC). Chemotherapy-induced neutropenia is one of the most serious adverse events associated with advanced PC. Although UGT1A1 polymorphisms are associated with the metabolism of irinotecan, their role as surrogate markers for FOLFIRINOX-induced neutropenia has not been confirmed. We investigated risk factors for FN-in particular, UGT1A1 polymorphisms-in PC patients receiving FOLFIRINOX, using a single-center cohort registry. To investigate the association between UGT1A1 polymorphisms and FN, we divided patients into three groups based on the predicted UGT1A1 phenotype: extensive metabolizer (EM) vs. intermediate metabolizer (IM) vs. poor metabolizer (PM). A total of 154 patients (FN group (n = 31) vs. non-FN group (n = 123)) receiving first-line FOLFIRINOX were identified between December 2017 and July 2020. The Cox regression analysis showed that female sex (HR: 2.20; p = 0.031), Eastern Cooperative Oncology Group performance status = 1 (HR: 2.83; p = 0.008), UGT1A1 IM (HR: 4.30; p = 0.004), and UGT1A1 PM (HR: 4.03; p = 0.028) were statistically significant risk factors for FN. We propose that UGT1A1 is the strongest predictive factor for FN and that this gene should be screened prior to the administration of chemotherapy.

Impact of UGT1A1 genotype on the efficacy and safety of irinotecan-based chemotherapy in metastatic colorectal cancer

The phase III AXEPT study showed the noninferiority of modified capecitabine plus irinotecan (mXELIRI) with or without bevacizumab relative to fluorouracil, leucovorin, and irinotecan (FOLFIRI) with or without bevacizumab as a second‐line treatment for metastatic colorectal cancer. We evaluated the associations between the UGT1A1 genotype linked to adverse events—caused by irinotecan—and the efficacy and safety of mXELIRI and FOLFIRI. The UGT1A1 genotype was prospectively determined and patients were categorized into three groups according to WT (*1/*1), single heterozygous (SH; *28/*1 or *6/*1), and double heterozygous or homozygous (DHH; *28/*28, *6/*6, or *28/*6). Overall survival (OS), progression‐free survival, response rate, and safety were assessed. The UGT1A1 genotype was available in all 650 randomized patients (WT, 309 [47.5%]; SH, 291 [44.8%]; DHH, 50 [7.7%]). The median OS was 15.9, 17.7, and 10.6 months in the WT, SH, and DHH groups, respectively, with an adjusted hazard ratio (HR) of 1.53 (95% confidence interval [CI], 1.12‐2.09; P = .008) for DHH vs WT or SH. The median OS in the mXELIRI and FOLFIRI arms was 18.1 vs 14.3 months (HR 0.80; 95% CI, 0.62‐1.03) in the WT group, 16.3 vs 18.3 months (HR 1.04; 95% CI, 0.79‐1.36) in the SH group, and 13.0 vs 9.1 months (HR 0.71; 95% CI, 0.39‐1.31) in the DHH group, respectively. Modified capecitabine plus irinotecan with or without bevacizumab could be a standard second‐line chemotherapy in terms of efficacy and safety regardless of the UGT1A1 genotype.

Collaborative Group of the Americas on Inherited Gastrointestinal Cancer Position statement on multigene panel testing for patients with colorectal cancer and/or polyposis

Multigene panel tests for hereditary cancer syndromes are increasingly utilized in the care of colorectal cancer (CRC) and polyposis patients. However, widespread availability of panels raises a number of questions including which patients should undergo testing, which genes should be included on panels, and the settings in which panels should be ordered and interpreted. To address this knowledge gap, key questions regarding the major issues encountered in clinical evaluation of hereditary CRC and polyposis were designed by the Collaborative Group of the Americas on Inherited Gastrointestinal Cancer Position Statement Committee and leadership. A literature search was conducted to address these questions. Recommendations were based on the best available evidence and expert opinion. This position statement addresses which genes should be included on a multigene panel for a patient with a suspected hereditary CRC or polyposis syndrome, proposes updated genetic testing criteria, discusses testing approaches for patients with mismatch repair proficient or deficient CRC, and outlines the essential elements for ordering and disclosing multigene panel test results. We acknowledge that critical gaps in access, insurance coverage, resources, and education remain barriers to high-quality, equitable care for individuals and their families at increased risk of hereditary CRC.

Genomic and epigenomic biomarkers in colorectal cancer: From diagnosis to therapy

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths in the United States. Despite ongoing efforts aimed at increasing screening for CRC and early detection, and development of more effective therapeutic regimens, the overall morbidity and mortality from this malignancy remains a clinical challenge. Therefore, identifying and developing genomic and epigenomic biomarkers that can improve CRC diagnosis and help predict response to current therapies are of paramount importance for improving survival outcomes in CRC patients, sparing patients from toxicity associated with current regimens, and reducing the economic burden associated with these treatments. Although efforts to develop biomarkers over the past decades have achieved some success, the recent availability of high-throughput analytical tools, together with the use of machine learning algorithms, will likely hasten the development of more robust diagnostic biomarkers and improved guidance for clinical decision-making in the coming years. In this chapter, we provide a systematic and comprehensive overview on the current status of genomic and epigenomic biomarkers in CRC, and comment on their potential clinical significance in the management of patients with this fatal malignancy, including in the context of precision medicine.

Pharmacogenomic Assessment of Patients with Colorectal Cancer and Potential Treatments

Evolving intensiveness of colorectal cancer (CRC) treatment, including chemotherapeutics and targeted agents associations, in adjuvant and metastatic CRC (MCRC) settings, increased overall survival (OS) with individual variability of toxicity. Pharmacogenomic guidelines recommended pre-treatment identification of at-risk patients suggesting dose adjustment of fluoropyrimidines based on dihydropyrimidine dehydrogenase (DPYD), and irinotecan on UDP glucuronosyl-transferase 1 family polypeptide A1 (UGT1A1) genetic variants, but they are poorly applied in clinical practice. This review highlighted clinically validated pharmacogenetic markers, to underline the need of their implementation in the multidisciplinary molecular board for individual CRC patients in clinical practice. Five clinically relevant DPYD variants with different prevalence impair enzymatic effectiveness and significantly increase toxicity: c.1236 G>A (c.1129–5923 C>G, HapB3), 4.1–4.8%; c.1679 T>G (DPYD*13), c.1905+1G>A (DPYD*2A), c.2846 A>T, c.2194 A>T (DPYD*6) 1% each. c.1679T>G and c.1905+1G>A are most deleterious on DPD effectiveness, moderately reduced in c.1236/HapB3 and c.2846A>T. Cumulatively, these variants explain approximately half of the estimated 10–15% fluoropyrimidine-related gastrointestinal and hematological toxicities due to DPD. Prevalent UGT1A1 gene [TA]₇TAA promoter allelic variant UGT1A1*28, characterized by an extra TA repeat, is associated with low transcriptional and reduced enzymatic effectiveness, decreased SN38 active irinotecan metabolite glucuronidation, vs wild-type UGT1A1*1 [A(TA)6TAA]. Homozygote UGT1A1*28 alleles patients are exposed to higher hematological and gastrointestinal toxicities, even more than heterozygote, at >150 mg/m² dose. Dose reduction is recommended for homozygote variant. Wild-type UGT1A1*28 alleles patients could tolerate increased doses, potentially affecting favorable outcomes. Implementation of up-front evaluation of the five validated DPYD variants and UGT1A1*28 in the multidisciplinary molecular tumor board, also including CRC genetic characterization, addresses potential treatments with fluoropyrimidines and irinotecan associations at proper doses and schedules, particularly for early CRC, MCRC patients fit for intensive regimens or unfit for conventional regimens, requiring treatment modulations, and also for patients who experience severe, unexpected toxicities. Integration of individual evaluation of toxicity syndromes (TS), specifically limiting TS (LTS), an innovative indicator of toxicity burden in individual patients, may be useful to better evaluate relationships between pharmacogenomic analyses with safety profiles and clinical outcomes.

A Systematic Review of the Value Assessment Frameworks Used within Health Technology Assessment of Omics Technologies and Their Actual Adoption from HTA Agencies

BACKGROUND

Omics technologies, enabling the measurements of genes (genomics), mRNA (transcriptomics), proteins (proteomics) and metabolites (metabolomics), are valuable tools for personalized decision-making. We aimed to identify the existing value assessment frameworks used by health technology assessment (HTA) doers for the evaluation of omics technologies through a systematic review.

METHODS

PubMed, Scopus, Embase and Web of Science databases were searched to retrieve potential eligible articles published until 31 May 2020 in English. Additionally, through a desk research in HTA agencies' repositories, we retrieved the published reports on the practical use of these frameworks.

RESULTS

Twenty-three articles were included in the systematic review. Twenty-two frameworks, which addressed genetic and/or genomic technologies, were described. Most of them derived from the ACCE framework and evaluated the domains of analytical validity, clinical validity and clinical utility. We retrieved forty-five reports, which mainly addressed the commercial transcriptomic prognostics and next generation sequencing, and evaluated clinical effectiveness, economic aspects, and description and technical characteristics.

CONCLUSIONS

A value assessment framework for the HTA evaluation of omics technologies is not standardized and accepted, yet. Our work reports that the most evaluated domains are analytical validity, clinical validity and clinical utility and economic aspects.

Determination of the UGT1A1 polymorphism as guidance for irinotecan dose escalation in metastatic colorectal cancer treated with first-line bevacizumab and FOLFIRI (PURE FIST)

AIM

Uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) polymorphism plays a crucial role in the increased susceptibility of patients to irinotecan and its toxicity. This study is a multicenter, randomised clinical trial comparing the clinical outcomes and adverse events (AEs) in metastatic colorectal cancer (mCRC) patients treated with bevacizumab plus FOLFIRI with or without UGT1A1 genotyping and irinotecan dose escalation as the first-line therapy.

METHODS

The control group received conventional biweekly FOLFIRI plus bevacizumab without UGT1A1 genotyping, whereas the study group received the same regimen with irinotecan dose escalation based on UGT1A1 genotyping. The primary end-point was progression-free survival (PFS), and secondary end-points were overall response rate (ORR), disease control rate (DCR), overall survival (OS), AEs and metastasectomy rate.

RESULTS

Over a median follow-up of 26.0 months (IQR, 17.0-35.0 months), study group (n = 107) was superior to the control group (n = 106) in PFS, OS, ORR, DCR, and metastasectomy rate (all P < 0.05). Furthermore, there were no significant differences in AEs ≥ grade III between the two groups, even with the 1.36-fold increase in the relative dose intensity of irinotecan in the study group. Dose escalation of irinotecan, an independent factor of ORR (P < 0.001) and DCR (P = 0.006), improved PFS in mCRC patients with wild-type and mutant KRAS (P = 0.007 and P = 0.019, respectively).

CONCLUSION

The current study revealed that mCRC patients, regardless of KRAS gene status, with UGT1A1 genotyping can tolerate escalated doses of irinotecan and potentially achieve a more favourable clinical outcome without significantly increased toxicities.

CLINICAL TRIAL REGISTRATION

NCT02256800.

Relevance of Pharmacogenomics and Multidisciplinary Management in a Young-Elderly Patient With KRAS Mutant Colorectal Cancer Treated With First-Line Aflibercept-Containing Chemotherapy

Introduction: Intensive oncological treatment integrated with resection of metastases raised the clinical outcome of metastatic colorectal cancer (MCRC). In clinical practice, complex evaluation of clinical (age, performance status, comorbidities), and biological (tumoral genotype, pharmacogenomic) parameters addresses tailored, personalized multidisciplinary treatment strategies. Patients with MCRC unsuitable for first-line intensive medical treatments are prevalent and showed worse clinical outcome. After progression to oxaliplatin-based chemotherapy, aflibercept/FOLFIRI significantly improved clinical outcome, even if no survival benefit was reported in adjuvant fast relapsers by aflibercept addition. The case reported a young-elderly (yE) patient with KRAS mutant colorectal cancer rapidly progressing to adjuvant chemotherapy, unfit owing to comorbidities, with multiple pharmacogenomic alterations, who gained long-term survival in clinical practice by multidisciplinary treatment strategy consisting of first-line and re-introduction of aflibercept-containing chemotherapy and two-stage lung metastasectomies.

Case presentation: A 71-years-old yE patient, unfit for intensive oncological treatments owing to Cumulative Illness Rating Scale (CIRS) stage secondary, affected by KRAS c.35 G>T mutant colorectal cancer, rapidly progressing with lung metastases after adjuvant XelOx chemotherapy, reached long-term survival 66 months with no evidence of disease after first-line and re-introduction of tailored, modulated aflibercept (4 mg/kg) d1,15-irinotecan (120 mg/m²) d1,15-5-fluorouracil (750 mg/m²/day) dd1–4, 15–18; and secondary radical bilateral two-stage lung metastasectomies. Safety profile was characterized by limiting toxicity syndrome at multiple sites (LTS-ms), requiring 5-fluorouracil discontinuation and aflibercept reduction (2 mg/kg), because of G2 hand-foot syndrome (HFS) for >2 weeks, and G3 hypertension. Pharmacogenomic analyses revealed multiple alterations of fluoropyrimidine and irinotecan metabolism: severe deficiency of fluorouracil degradation rate (FUDR), single nucleotide polymorphisms of UGT1A1^*28 variable number of tandem repeats (VNTR) 7R/7R homozygote, ABCB1 c.C3435T, c.C1236T, MTHFR c.C667T homozygote, DPYD c.A166G, TSER 28bp VNTR 2R/3R heterozygote.

Conclusions: In clinical practice, a complex management evaluating clinical parameters and RAS/BRAF genotype characterizing an individual patient with MCRC, particularly elderly and/or unfit owing to comorbidities, is required to properly address tailored, multidisciplinary medical and surgical treatment strategies, integrated with careful monitoring of superimposing toxicity syndromes, also related to pharmacogenomic alterations, to gain optimal activity, and long-term efficacy.

Individualization of Irinotecan Treatment: A Review of Pharmacokinetics, Pharmacodynamics, and Pharmacogenetics

Since its clinical introduction in 1998, the topoisomerase I inhibitor irinotecan has been widely used in the treatment of solid tumors, including colorectal, pancreatic, and lung cancer. Irinotecan therapy is characterized by several dose-limiting toxicities and large interindividual pharmacokinetic variability. Irinotecan has a highly complex metabolism, including hydrolyzation by carboxylesterases to its active metabolite SN-38, which is 100- to 1000-fold more active compared with irinotecan itself. Several phase I and II enzymes, including cytochrome P450 (CYP) 3A4 and uridine diphosphate glucuronosyltransferase (UGT) 1A, are involved in the formation of inactive metabolites, making its metabolism prone to environmental and genetic influences. Genetic variants in the DNA of these enzymes and transporters could predict a part of the drug-related toxicity and efficacy of treatment, which has been shown in retrospective and prospective trials and meta-analyses. Patient characteristics, lifestyle and comedication also influence irinotecan pharmacokinetics. Other factors, including dietary restriction, are currently being studied. Meanwhile, a more tailored approach to prevent excessive toxicity and optimize efficacy is warranted. This review provides an updated overview on today’s literature on irinotecan pharmacokinetics, pharmacodynamics, and pharmacogenetics.

Germline mismatch repair gene variants analyzed by universal sequencing in Japanese cancer patients

Background

Lynch syndrome (LS) is the commonest inherited cancer syndrome caused by pathogenic variants of germline DNA mismatch repair (g.MMR) genes. Genome‐wide sequencing is now increasingly applied for tumor characterization, but not for g.MMR. The aim of this study was to evaluate the incidence and pathogenicity of g.MMR variants in Japanese cancer patients.

Methods

Four g.MMR genes (MLH1, MSH2, MSH6, and PMS2) were analyzed by next generation sequencing in 1058 cancer patients (614 male, 444 female; mean age 65.6 years) without past diagnosis of LS. The g.MMR variant pathogenicity was classified based on the ClinVar 2015 database. Tumor MMR immunohistochemistry, microsatellite instability (MSI), and BRAF sequencing were also investigated in specific cases.

Results

Overall, 46 g.MMR variants were detected in 167 (15.8%) patients, 17 likely benign variants in 119 patients, 24 variants of uncertain significance (VUSs) in 68 patients, two likely pathogenic variants in two patients, and three pathogenic variants in three (0.3%) patients. The three pathogenic variants included two colorectal cancers with MLH1 loss and high MSI and one endometrial cancer with MSH6 loss and microsatellite stability. Two likely pathogenic variants were shifted to VUSs by ClinVar (2018). One colon cancer with a likely benign variant demonstrated MLH1 loss and BRAF mutation, but other nonpathogenic variants showed sustained MMR and microsatellite stability.

Conclusions

Universal sequencing of g.MMR genes demonstrated sundry benign variants, but only a small proportion of cancer patients had pathogenic variants. Pathogenicity evaluation using the ClinVar database agreed with MSI, MMR immunohistochemistry, and BRAF sequencing.

Intensive first-line FIr-C/FOx-C association of triplet chemotherapy plus cetuximab in RAS wild-type metastatic colorectal cancer patients: preliminary phase II data and prediction of individual limiting toxicity syndromes by pharmacogenomic biomarkers

Background:

Intensive triplet chemotherapy/bevacizumab significantly increased metastatic colorectal cancer (MCRC) outcome. This phase II study investigated the safety/activity of FIr-C/FOx-C triplet/cetuximab (CET) in first-line RAS wild-type and the prediction of individual limiting toxicity syndromes (LTS) by pharmacogenomic biomarkers.

Methods:

A Simon two-step design was used: p0 70%, p1 85%, power 80%, α5%, β20%; projected objective response rate (ORR) I step 14/19. FIr-C/FOx-C: 5-fluorouracil (5-FU) 12h-timed flat infusion 900 mg/m² d1–2, 8–9, 15–16, 22–23; irinotecan (CPT-11) 160 mg/m² d1 and 15, oxaliplatin 80 mg/m² d8 and 22; CET 400mg/m² then 250 mg/m² d1, 8, 15, 22; every 28 days. Toxicity, and individual LTS were evaluated, compared by a Chi-square test; and activity/efficacy by log-rank. 5-FU/CPT-11 pharmacogenomic biomarkers, 5-FU degradation rate (5-FUDR), single nucleotide polymorphisms (SNPs) ABCB1, CYP3A4, DYPD, UGT1A1 were evaluated in patients with LTS and at a recommended dose.

Results:

A total of 29 patients <75 years, with a primary/intermediate Cumulative Index Rating Scale were enrolled; the median age was 59 years; there were 7 young-elderly (yE; 24%). Recommended CPT-11/5-FU doses were 120/750 mg/m². In the intent-to-treat analysis, the ORR was 58.6%. The primary endpoint was met in patients who received the planned three treatment cycles: the objective response (OR) was 14/18 (78%). At a median follow up of 18 months, progression-free survival (PFS) was 12, and overall survival (OS) was 23 months. At the recommended doses (received dose intensity >80%), grade 3–4 toxicities were: diarrhea 23%, asthenia 15%, vomiting 8%, hypertransaminasemy 8%; LTS 19 (65.5%), with 83% in yE patients. LTS prevalently multiple (ms) versus single site were 59% versus 7% (p = 0.006). The prevalence of reduced FUDR was 56%, SNPs CYP3A4 22%, UGT1A1 71%, and of >2 positive pharmacogenomics biomarkers was 78%, prevalently reported in patients who developed gastrointestinal LTS.

Conclusions:

FIr-C/FOx-C is highly active and tolerable at recommended doses in non-elderly RAS wild-type MCRC patients. LTS provided an evaluation of the toxicity burden in individual patients. Reduced FUDR, CYP3A4, and UGT1A1 SNPs may predict individual LTS-ms in patients at risk of limiting gastrointestinal toxicity.

Trial registration:

The trial was registered at Osservatorio Nazionale sulla Sperimentazione Clinica dei Medicinali (OsSC) Agenzia Italiana del Farmaco (AIFA) Numero EudraCT 2009-016793-32.

Germline susceptibility variants impact clinical outcome and therapeutic strategies for stage III colorectal cancer

Although somatic mutations are the main cause of cancer, underlying germline alterations may affect cancer outcome. There is little information on comprehensive analysis of germline genome sequencing for cancer healthcare strategy. Here we studied the implication of germline cancer-associated variants on cancer counselling and therapeutic strategies by germline whole genome and tumor targeted sequencing. Fifty-five gynecological and 104 colorectal cancer (CRC) patients were enrolled. We identified 22 germline pathogenic variants in 16 cancer-associated genes. Most of them are involved in DNA repair signaling, including MLH1, BRCA1/2, MUTYH, ATM, PMS2, MSH6, BAP1, and FANCA. About 6% of cancer patients presented the secondary findings of germline variants with non-oncogenic impact, mainly on the cardiovascular system which should be carefully monitored during chemotherapy. CRC patients carrying germline susceptibility variants had better disease-free survival than those without variants. Importantly, in the CRC model, the underlying germline alterations mold the tumor somatic alteration landscape. NOTCH1 mutation was the most common somatic mutation in recurrent CRC, implying a potential therapeutic target in adjuvant setting. In conclusion, both tumor genome and germline sequence data have to be analyzed to have a more complete picture of the overall genetic foundation of cancer.

Relative Dose Intensity of Induction-Phase Pazopanib Treatment of Soft Tissue Sarcoma: Its Relationship with Prognoses of Pazopanib Responders

The approved standard dose of pazopanib is 800 mg per day, but the appropriate dose of pazopanib to treat soft tissue sarcoma (STS) patients in real-world practice is controversial. Of 124 STS patients treated with pazopanib, we retrospectively analyzed the cases of STS patients who achieved progression-free survival at 12 weeks by pazopanib treatment as pazopanib responders, and we evaluated their relative dose intensity (RDI) in the initial 12 weeks (12W-RDI). We enrolled 78 STS patients in the analyses as pazopanib responders, and 54 patients of the 78 pazopanib responders (69%) were able to maintain 12W-RDI ≥80%. In landmark analyses, patients with 12W-RDI of 80% ≥80% had significantly longer progression-free survival compared to those with 12W-RDI <80% (30.7 weeks vs. 22.0 weeks, hazard ratio [HR]: 0.56 [95%CI: 0.33–0.94], p = 0.026). The most frequently observed reasons of treatment interruption and/or dose reduction of pazopanib during the initial 12 weeks were anorexia and liver function disorders. Liver toxicity was the adverse event most frequently observed in the 12W-RDI <80% patients throughout the treatment periods. Based on our results, it appears that maintaining as high a dose intensity as possible that is tolerable—at least during the initial 12 weeks—is likely to be the better option in pazopanib treatment for STS patients.

UGT1A1 (TA)n Promoter Genotype: Diagnostic and Population Pharmacogenetic Marker in Serbia

The UGT1A1 enzyme is involved in the metabolism of bilirubin and numerous medications. Unconjugated hyperbilirubinemia, commonly presented as Gilbert syndrome (GS), is a result of decreased activity of the UGT1A1 enzyme, variable number of TA repeats in the promoter of the UGT1A1 gene affects enzyme activity. Seven and eight TA repeats cause a decrease of UGT1A1 activity and risk GS alleles, while six TA repeats contribute to normal UGT1A1 activity and non-risk GS allele. Also, the UGT1A1 (TA)_n promoter genotype is recognized as a clinically relevant pharmacogenetic marker. The aim of this study was to assess diagnostic value of UGT1A1 (TA)_n promoter genotyping in pediatric GS patients. Correlation of the UGT1A1 (TA)_n genotypes and level of unconjugated bilirubin at diagnosis and after hypocaloric and phenobarbitone tests in these patients was analyzed. Another aim of the study was to assess pharmacogenetic potential of UGT1A1 (TA)_n variants in Serbia. Fifty-one pediatric GS patients and 100 healthy individuals were genotyped using different methodologies, polymerase chain reaction (PCR) followed by acrylamide electrophoresis, fragment length analysis and/or DNA sequencing. Concordance of the UGT1A1 (TA)_n promoter risk GS genotypes with GS was found in 80.0% of patients. Therefore, UGT1A1 (TA)_n promoter genotyping is not a reliable genetic test for GS, but it is useful for differential diagnosis of diseases associated with hyperbilirubinemia. Level of bilirubin in pediatric GS patients at diagnosis was UGT1A1 (TA)_n promoter genotype-dependent. We found that the frequency of pharmacogenetic relevant UGT1A1 (TA)_n promoter genotypes was 63.0%, pointing out that UGT1A1 (TA)_n promoter genotyping could be recommended for preemptive pharmacogenetic testing in Serbia.

Real life triplet FIr/FOx chemotherapy in first-line metastatic pancreatic ductal adenocarcinoma patients: recommended schedule for expected activity and safety and phase II study

BACKGROUND

Gemcitabine/nab-paclitaxel and FOLFIRINOX demonstrated significantly increased survival compared with gemcitabine in metastatic pancreatic ductal adenocarcinoma (PDAC): objective response rate (ORR) 23 and 31.6%, progression-free survival (PFS) 5.5 and 6.4 months, overall survival (OS) 8.7 and 11.1 months. Present phase II study evaluated recommended first-line triplet FIr/FOx schedule.

METHODS

Simon two-step design: p010%, p130%, power 80%, α5%, β20%. Projected ORR: I step, 1/10; II 5/29. Schedule: 12h-timed-flat-infusion/5-fluorouracil 750-800-900 mg/m2 d1-2,8-9,15-16,22-23; irinotecan 120-140-160 mg/m2 d1,15; oxaliplatin 70-80 mg/m2 d8,22; every 4 weeks, according to clinical parameters (age, comorbidities, performance status (PS), liver function). Activity and efficacy were evaluated, and compared using log-rank; limiting toxicity syndromes (LTS), using chi-square.

RESULTS

Twenty-nine consecutive patients were enrolled, according to primary/intermediate/secondary Cumulative Illness Rating Scale (CIRS). Median age 62; elderly 13 (44.7%); PS2 3 (10.4%), secondary CIRS 5 (17.2%). Primary endpoint was met: ORR 53% (7/13 patients) as-treated, 50% intent-to-treat. Cumulative G3-4 toxicities: diarrhea 17%, asthenia 14%, hypertransaminasemy 7%, mucositis 7%, vomiting 3%, anemia 3%, thrombocytopenia 3%. LTS were 27.5% overall, 38.4% in elderly. At 3 months median follow-up, PFS 4 months, OS 11 months. PS2 patients showed significantly worse OS (P 0.022).

CONCLUSION

Intensive first-line triplet FIr/FOx is tolerable at modulated doses, and confirms high activity/efficacy in metastatic PDAC. Patients' careful selection, and exclusion of PS2, can maintain safety profile and efficient dose intensity.

Systemic Treatments for Lung Cancer Patients Receiving Hemodialysis

Chemotherapy, and now targeted therapies and immunotherapies, are widely used for the management of patients with all stages of lung cancer. Some challenges present when patients are receiving concomitant hemodialysis for various comorbid conditions. However, this should not immediately rule out a patient for treatment. Many drugs may be safely given to patients who are receiving hemodialysis with the proper dosing schedule and careful monitoring. This article will outline the current literature surrounding the use of these drugs in patients undergoing active hemodialysis while being treated for lung cancer.

Irinotecan-induced muscle twitching from a possible drug interaction: A case report

We report the case of a 50-year-old human immunodeficiency virus-positive patient with stage IV KRAS-mutated colorectal cancer who experienced visible muscle twitching in the right lateral triceps brachii from irinotecan administration for which typical supportive care measures were unsuccessful, including the administration of atropine and slowing down the infusion rate. The patient was able to tolerate this reaction and received 20 cycles of irinotecan-based chemotherapy despite experiencing the muscle twitching with every cycle at the same onset, duration, and severity. It is possible that competitive metabolism by concomitant medications metabolized by CYP3A4 or UGT1A1 was responsible for this event. Due to ethical concerns, we were unable to formally assess the drug interaction by discontinuing the suspected interacting medications and re-initiating them to evaluate the effects. A formal pharmacokinetic study may be warranted to better elucidate these potential drug interactions.

Molecular subtypes of metastatic colorectal cancer are associated with patient response to irinotecan-based therapies

BACKGROUND

Currently, metastatic colorectal cancer is treated as a homogeneous disease and only RAS mutational status has been approved as a negative predictive factor in patients treated with cetuximab. The aim of this study was to evaluate if recently identified molecular subtypes of colon cancer are associated with response of metastatic patients to first-line therapy.

PATIENTS AND METHODS

We collected and analysed 143 samples of human colorectal tumours with complete clinical annotations, including the response to treatment. Gene expression profiling was used to classify patients in three to six classes using four different molecular classifications. Correlations between molecular subtypes, response to treatment, progression-free and overall survival were analysed.

RESULTS

We first demonstrated that the four previously described molecular classifications of colorectal cancer defined in non-metastatic patients also correctly classify stage IV patients. One of the classifications is strongly associated with response to FOLFIRI (P=0.003), but not to FOLFOX (P=0.911) and FOLFIRI + Bevacizumab (P=0.190). In particular, we identify a molecular subtype representing 28% of the patients that shows an exceptionally high response rate to FOLFIRI (87.5%). These patients have a two-fold longer overall survival (40.1 months) when treated with FOLFIRI, as first-line regimen, instead of FOLFOX (18.6 months).

CONCLUSIONS

Our results demonstrate the interest of molecular classifications to develop tailored therapies for patients with metastatic colorectal cancer and a strong impact of the first-line regimen on the overall survival of some patients. This however remains to be confirmed in a large prospective clinical trial.

UGT1A1*28 relationship with abnormal total bilirubin levels in chronic hepatitis C patients: Outcomes from a case-control study

Gilbert syndrome (GS) is a frequent benign clinical condition, marked by intermittent unconjugated hyperbilirubinemia, mostly due to the polymorphism uridine diphosphate-glucuronosyltransferase 1A1*28 (UGT1A1*28). Hyperbilirubinemia has been reported in a GS patient undergoing hepatitis C treatment, and other UGT isoforms polymorphisms have been linked to worse outcomes in viral hepatitis. Yet, little is known to GS contributions' to the liver disease scenario. Our aim was to assess UGT1A1 genotypes' frequency in chronic hepatitis C (CHC) patients and correlate with total bilirubin (TB). This is a case-control study in a large tertiary medical center. Cases were CHC patients confirmed by hepatitis C virus (HCV)-polymerase chain reaction. Exclusion criteria were hepatitis B virus or human immunodeficiency virus (HIV) coinfection. Control were healthy blood donors. UGT1A1 promoter region gene genotyping was performed, and bilirubin serum levels were available for HCV patients. Genotypes and alleles frequencies were similar in case (n = 585; P = 0.101) and control groups (n = 313; P = 0.795). Total bilirubin increase was noticed according to thymine-adenine repeats in genotypes (P < 0.001), and the TB greater than 1 mg/dL group had more UGT1A1*28 subjects than in the group with TB values <1 mg/dL (18.3 vs 5.3; P < 0.001). Bilirubin levels are linked to the studied polymorphisms, and this is the first time that these findings are reported in a chronic liver disease sample. Among patients with increased TB levels, the frequency of UGT1A1*28 is higher than those with normal TB. Personalized care should be considered to GS, regarding either abnormal bilirubin levels or drug metabolism.

The Routine Clinical use of Pharmacogenetic Tests: What it Will Require?

Pharmacogenetic testing aims to personalize drug therapy with a view to optimising drug efficacy and minimise toxicity. However, despite the potential benefits, pharmacogenetic testing is mostly confined to specialised medical areas, laboratories and centres. Widespread integration into routine clinical practice has been limited by a complex set of issues including regulatory and reimbursement frameworks, evidence of clinical utility and clinician perspectives, practices and education. Here we assess the current barriers to widespread clinical uptake and identify the key issue necessary to address to accelerate routine testing.

Recent advances in understanding Lynch syndrome

Colorectal cancer affects about 4.4% of the population and is a leading cause of cancer-related death in the United States. Approximately 10% to 20% of cases occur within a familial pattern, and Lynch syndrome is the most common hereditary colorectal cancer syndrome. Lynch syndrome is a hereditary predisposition to forming colorectal and extracolonic cancers, caused by a germline mutation in one of the DNA mismatch repair genes. Identifying at-risk patients and making a correct diagnosis are the keys to successful screening and interventions which will decrease formation of and death from cancers. Knowledge of the genetics and the natural history of Lynch syndrome has continued to be uncovered in recent years, leading to a better grasp on how these patients and their families should be managed. Recent developments include the approach to diagnostic testing, more precise definitions of the syndrome and risk stratification based on gene mutations, surgical decision-making, and chemoprevention.

The future of clinical cancer genomics

The current and future applications of genomics to the practice of preventive oncology are being impacted by a number of challenges. These include rapid advances in genomic science and technology that allow massively parallel sequencing of both tumors and the germline, a diminishing of intellectual property restrictions on diagnostic genetic applications, rapid expansion of access to the internet which includes mobile access to both genomic data and tools to communicate and interpret genetic data in a medical context, the expansion of for-profit diagnostic companies seeking to monetize genetic information, and a simultaneous effort to depict medical professionals as barriers to rather than facilitators of understanding one's genome. Addressing each of these issues will be required to bring "personalized" germline genomics to cancer prevention and care. A profound future challenge will be whether clinical cancer genomics will be "de-medicalized" by commercial interests and their advocates, or whether the future course of this field can be modulated in a responsible way that protects the public health while implementing powerful new medical tools for cancer prevention and early detection.

Advances in Biomarkers: Going Beyond the Carcinoembryonic Antigen

Using biologically available markers to guide treatment decisions in colorectal cancer care is becoming increasingly common, though our understanding of these biomarkers is in its infancy. In this article, we will discuss how this area is rapidly changing, review important biomarkers being used currently, and explain how the results influence clinical decision-making. We will also briefly discuss the possibility of a liquid biopsy and explore several exciting and new options.

Mismatch repair deficiency testing in clinical practice

Lynch syndrome, an autosomal dominant inherited disorder, is caused by inactivating mutations involving DNA mismatch repair (MMR) genes. This leads to profound genetic instability, including microsatellite instability (MSI) and increased risk for cancer development, particularly colon and endometrial malignancies. Clinical testing of tumor tissues for the presence of MMR gene deficiency is standard practice in clinical oncology, with immunohistochemistry and PCR-based microsatellite instability analysis used as screening tests to identify potential Lynch syndrome families. The ultimate diagnosis of Lynch syndrome requires documentation of mutation within one of the four MMR genes (MLH1, PMS2, MSH2 and MSH6) or EPCAM, currently achieved by comprehensive sequencing analysis of germline DNA. In this review, the genetic basis of Lynch syndrome, methodologies of MMR deficiency testing, and current diagnostic algorithms in the clinical management of Lynch syndrome, are discussed.

Expert and Advocacy Group Consensus Findings on the Horizon of Public Health Genetic Testing

Description: Among the two leading causes of death in the United States, each responsible for one in every four deaths, heart disease costs Americans $300 billion, while cancer costs Americans $216 billion per year. They also rank among the top three causes of death in Europe and Asia. In 2012 the University of Michigan Center for Public Health and Community Genomics and Genetic Alliance, with the support of the Centers for Disease Control and Prevention Office of Public Health Genomics, hosted a conference in Atlanta, Georgia to consider related action strategies based on public health genomics. The aim of the conference was consensus building on recommendations to implement genetic screening for three major heritable contributors to these mortality and cost figures: hereditary breast and ovarian cancer (HBOC), familial hypercholesterolemia (FH), and Lynch syndrome (LS). Genetic applications for these three conditions are labeled with a “Tier 1” designation by the U.S. Centers for Disease Control and Prevention because they have been fully validated and clinical practice guidelines based on systematic review support them. Methodology: The conference followed a deliberative sequence starting with nationally recognized clinical and public health presenters for each condition, followed by a Patient and Community Perspectives Panel, working group sessions for each of the conditions, and a final plenary session. The 74 conference participants represented disease research and advocacy, public health, medicine and nursing, genetics, governmental health agencies, and industry. Participants drew on a public health framework interconnecting policy, clinical intervention, surveillance, and educational functions for their deliberations. Results: Participants emphasized the importance of collaboration between clinical, public health, and advocacy groups in implementing Tier 1 genetic screening. Advocacy groups could help with individual and institutional buy-in of Tier 1 programs. Groups differed on funding strategies, with alternative options such as large-scale federal funding and smaller scale, incremental funding solutions proposed. Piggybacking on existing federal breast and colorectal cancer control programs was suggested. Public health departments need to assess what information is now being collected by their state cancer registries. The groups advised that information on cascade screening of relatives be included in toolkits for use by states. Participants stressed incorporation of family history into health department breast cancer screening programs, and clinical HBOC data into state surveillance systems. The carrying out of universal LS screening of tumors in those with colorectal cancer was reviewed. Expansion of universal screening to include endometrial tumors was discussed, as was the application of guidelines recommending cholesterol screening of children 9–11 years old. States more advanced in terms of Tier 1 testing could serve as models and partners with other states launching screening and surveillance programs. A multidisciplinary team of screening program champions was suggested as a means of raising awareness among the consumer and health care communities. Participants offered multiple recommendations regarding use of electronic health records, including flagging of at-risk family members and utilization of state-level health information exchanges. The paper contains an update of policy developments and happenings for all three Tier 1 conditions, as well as identified gaps. Conclusions: Implementation of cascade screening of family members for HBOC and FH, and universal screening for LS in CRC tumors has reached a point of readiness within the U.S., with creative solutions at hand. Facilitating factors such as screening coverage through the Patient Protection and Affordable Care Act, and state health information exchanges can be tapped. Collaboration is needed between public health departments, health care systems, disease advocacy groups, and industry to fully realize Tier 1 genetic screening. State health department and disease networks currently engaged in Tier 1 screening can serve as models for the launch of new initiatives.

Clinical Implication of UGT1A1 Promoter Polymorphism for Irinotecan Dose Escalation in Metastatic Colorectal Cancer Patients Treated with Bevacizumab Combined with FOLFIRI in the First-line Setting

PURPOSE

This study aimed to identify the efficacy and toxicity of the FOLFIRI regimen (fluorouracil, leucovorin, and irinotecan) with irinotecan dose escalation plus bevacizumab as first-line chemotherapy for metastatic colorectal cancer (mCRC) via UGT1A1 genotyping.

METHODS

We administered bevacizumab plus FOLFIRI with irinotecan dose escalation to treat 70 mCRC patients. The UGT1A1 *1/*1 and *1/*28 genotypes started with a 180-mg/m(2) dose of irinotecan, and UGT1A1 *28/*28 genotype started with a dose of 120 mg/m(2). The dose of irinotecan was escalated at increasing intervals of 20 to 30 mg/m(2) until grade 3/4 adverse events (AEs) occurred. The clinical response rate, toxicity, and survival were analyzed.

RESULTS

The clinical response and disease control rates of mCRC patients treated with FOLFIRI plus bevacizumab were significantly better in patients with UGT1A1 *1/*1 and *1/*28 genotypes than in patients with UGT1A1 *28/*28 (P = .006 and P < .001, respectively). Grade 3/4 AEs were significantly more common in mCRC patients with the UGT1A1 *28/*28 genotype (P < .001). Progression-free survival was significantly higher in UGT1A1 *1/*1 and *1/*28 patients (P = .002). mCRC patients who underwent metastasectomy achieved better overall survival than those who did not undergo metastasectomy (P = .015).

CONCLUSIONS

Our study showed that mCRC patients with UGT1A1 *1/*1 and *1/*28 genotypes could receive escalated doses of irinotecan to obtain a more favorable clinical outcome without significant AEs.

Cisplatin combined with irinotecan or etoposide for untreated extensive-stage small cell lung cancer: A multicenter randomized controlled clinical trial

Background

This study evaluated the efficacy and safety of irinotecan/cisplatin (IP) and etoposide/cisplatin (EP) in extensive-stage small cell lung cancer (ES-SCLC) and the distribution of uridine diphosphate glucuronosyltransferase (UGT1A1). The relationship between UGT1A1 genotypes and patient outcomes was also assessed.

Method

Patients with untreated ES-SCLC were randomly assigned to receive either IP or EP, and blood specimens were collected to test the genotypes of UGT1A1*28 and UGT1A1*6. The association of efficacy and toxicity of an IP regimen with UGT1A1 genotype was analyzed.

Results

Of the 62 patients enrolled from three institutions, 30 patients were in the IP and 32 patients were in the EP arms, respectively. Disease control rates with IP and EP were 83.3% and 71.9%, respectively (P = 0.043). Median progression-free survival for IP and EP were both six months. Median overall survival for IP and EP were 18.1 and 15.8 months respectively, without significant difference. Grade 3-4 thrombocytopenia was more common with EP (18.8% vs. 6.7%; P = 0.035), while the incidence of diarrhea was higher with IP (70% vs. 15.6%; P = 0.008). The incidence of grade 1-4 late-onset diarrhea of wild-type, heterozygous, and homozygous UGT1A1*28 were 65.0%, 85.7%, and 66.7%, respectively (P = 0.037). UGT1A1*28 polymorphisms, Eastern Cooperative Oncology Group performance status, and chemotherapy cycles were essential factors affecting grade 1-4 late-onset diarrhea in logistic regression analysis.

Conclusions

The efficacy of the IP regimen was similar to the EP regimen for untreated ES-SCLC. UGT1A1 polymorphisms were associated with late-onset diarrhea; however, there was no influence on efficacy.

The cost-effectiveness of UGT1A1 genotyping before colorectal cancer treatment with irinotecan from the perspective of the German statutory health insurance

BACKGROUND

The evidence concerning the cost-effectiveness of UGT1A1*28 genotyping is ambiguous and does not allow drawing valid conclusions for Germany. This study evaluates the cost-effectiveness of UGT1A1 genotyping in patients with metastatic colorectal cancer undergoing irinotecan-based chemotherapy compared to no testing from the perspective of the German statutory health insurance.

MATERIAL AND METHODS

A decision-analytic Markov model with a life time horizon was developed. No testing was compared to two genotype-dependent therapy strategies: 1) dose reduction by 25%; and 2) administration of a prophylactic G-CSF growth factor analog for homozygous and heterozygous patients. Probability, quality of life and cost parameters used in this study were based on published literature. Deterministic and probabilistic sensitivity analyses were performed to account for parameter uncertainties.

RESULTS

Strategy 1 dominated all remaining strategies. Compared to no testing, it resulted in only marginal QALY increases (0.0002) but a cost reduction of €580 per patient. Strategy 2 resulted in the same health gains but increased costs by €10 773. In the probabilistic analysis, genotyping and dose reduction was the optimal strategy in approximately 100% of simulations at a threshold of €50 000 per QALY. Deterministic sensitivity analysis shows that uncertainty for this strategy originated primarily from costs for irinotecan-based chemotherapy, from the prevalence of neutropenia among heterozygous patients, and from whether dose reduction is applied to both homozygotes and heterozygotes or only to the former.

CONCLUSION

This model-based synthesis of the most recent evidence suggests that pharmacogenetic UGT1A1 testing prior to irinotecan-based chemotherapy dominates non-personalized colon cancer care in Germany. However, as structural uncertainty remains high, these results require validation in clinical practice, e.g. based on a managed-entry agreement.

A single institution experience in compliance with universal screening for Lynch syndrome in colorectal cancer

BACKGROUND

Detection of Lynch syndrome has the potential to reduce morbidity and mortality among patients and their family members due to beneficial screening and treatment options. Several institutions have begun to adopt universal rather than risk-stratified screening protocols, but the lack of 100 % compliance rates requires identification of system-level interventions to improve screening practices.

OBJECTIVE

We aimed to identify patient, tumor, and system factors associated with lack of screening and identify system-based interventions to improve Lynch syndrome screening.

DESIGN AND SETTINGS

This study is a retrospective analysis of Lynch syndrome screening among colorectal cancer patients undergoing surgery in a single healthcare system.

PATIENTS

Two hundred and sixty-two patients who underwent surgery for colorectal cancer were studied.

MAIN OUTCOME MEASURES

Rate of Lynch syndrome screening.

RESULTS

We identified that 75 % of the total cohort was screened for Lynch syndrome. Of patients under the age of 50, 78 % percent were screened. Lower screening rates were found among patients with complete pathologic tumor response and lower pathologic stage of tumor. Higher screening rates were found at the academic hospital and with colorectal surgeons. In multivariable logistic regression analysis, lower screening rates were associated with community hospital location (OR, 0.22; 95 % CI, 0.08-0.56).

LIMITATIONS

Results may not be generalizable to different hospital settings.

CONCLUSIONS

Several potential system-level interventions were identified to improve screening rates including an emphasis on improved provider communication.

Clinical observations on associations between the UGT1A1 genotype and severe toxicity of irinotecan

BACKGROUND

Severe toxicity is commonly observed in cancer patients receiving irinotecan (CPT-11). UDP glucuronosyltransferase1A1 (UGT1A1) catalyzes the glucuronidation of the active metabolite SN-38 but the relationship between UGT1A1 and severe toxicity remains unclear. Our study aimed to assess this point to guide clinical use of CPT-11.

MATERIALS AND METHODS

89 cancer patients with advanced disease received CPT-11-based chemotherapy for at least two cycles. Toxicity, including GI and hematologic toxicity was recorded in detail and UGT1A1 variants were genotyped. Regression analysis was used to analyse relationships between these variables and tumor response.

RESULTS

The prevalence of grade III-IV diarrhea was 10.1%, this being more common in patients with the TA 6/7 genotype (5 of 22 patients, 22.7%) (p<0.05). The prevalence of grade III-IV neutropenia was 13.4%and also highest in patients with the TA 6/7 genotype (4 of 22 patients; 18.2%) but without significance (p>0.05). The retreatment total bilirubin levels were significantly higher in TA6/7 patients (mean, 12.75μmol/L) with compared to TA6/6 (mean, 9.92 μmol/L) with p<0.05.

CONCLUSIONS

Our study support the conclusion that patients with a UGT1A1*28 allele (s) will suffer an increased risk of severe irinotecan-induced diarrhea, whether with mid-or low-dosage. However, the UGT1A1*28 allele (s) did not increase severe neutropenia. Higher serum total bilirubin is an indication that patients UGT1A1 genotype is not wild-type, with significance for clinic usage of CPT-11.

The number of intestinal bacteria is not critical for the enhancement of antitumor activity and reduction of intestinal toxicity of irinotecan by the Chinese herbal medicine PHY906 (KD018)

Background

The four-herb Chinese medicine PHY906(KD018) has been shown to both enhance the in vivo antitumor activity of irinotecan (CPT-11) against colon cancer tumor allografts and alleviate intestinal toxicity caused by CPT-11.

Methods

Since intestinal bacteria can metabolize CPT-11 and PHY906, we investigated whether intestinal bacteria play a critical role in the in vivo activity of PHY906 in murine Colon-38 tumor-bearing mice. Intestinal bacteria were depleted using streptomycin/neomycin for 10 days before and during treatment with PHY906 and/or CPT-11. qPCR using 16S DNA group-specific primers was used to quantify the levels of the major intestinal bacteria.

Results

Both PHY906 and antibiotic treatment changed the profile of intestinal bacteria species: Lactobacillus/Enterococcus, Bacteroides, Clostridium leptum, and E. rectale/C. coccoides. Antibiotic treatment did not alter the ability of PHY906 to enhance the antitumor activity of CPT-11. Antibiotic treatment alone partially reduced animal body weight loss in CPT-11-treated mice. However, PHY906 treatment was able to protect against the body weight loss in the CPT-11/antibiotic treatment group. H&E and PCNA staining of intestine showed that antibiotic treatment partially reduced the intestinal damage caused by CPT-11 but not as effectively as PHY906 treatment. Antibiotic treatment plus PHY906 conferred the most effective protection of intestine histological structure against damage by CPT-11. Both PHY906 and antibiotic treatment inhibited CPT-11-associated inflammatory processes, including infiltration of the intestine by neutrophils, MCP1 and TNF-alpha mRNA expression in the intestine, and expression of pro-inflammatory cytokines G-CSF and MCP1 proteins in the plasma. However, whereas antibiotic treatment suppressed the mRNA expression of two important intestinal progenitor/stem cell markers, Olfm4 and Lgr5, PHY906 treatment resulted in enhanced expression of these two stem cell markers.

Conclusions

Alterations in the population of intestinal bacteria did not affect the abilities of PHY906 to enhance CPT-11 antitumor activity or reduce the intestinal toxicity associated with CPT-11 treatment. The major species of intestinal bacteria do not appear to play a role in PHY906’s enhancement of the therapeutic index of CPT-11 in tumor-bearing mice. Thus, patients with different intestinal bacterial profiles may still benefit from PHY906 treatment alongside CPT-11.

The power of genes: a case of unusually severe systemic toxicity after localized hepatic chemoembolization with irinotecan-eluted microspheres for metastatic colon cancer

OBJECTIVE

To report a case of systemic irinotecan toxicity following regional transarterial chemoembolization with drug-eluting beads loaded with irinotecan (DEBIRI-TACE) in a patient later found to have a homozygous mutation for UGT1A1*28.

CASE SUMMARY

An 80-year-old woman presented with a cecal colon cancer with synchronous metastases to the liver. After resection of the primary tumor, the patient underwent DEBIRI-TACE with 100 mg of irinotecan to treat the residual disease in the liver. A week after this procedure, the patient developed grade 4 neutropenia, and later, alopecia. Eventually, it was found that the patient had a mutation of UDP glucuronosyltransferase 1 family polypeptide A1 (UGT1A1), which provided a reasonable explanation for the observed reaction.

DISCUSSION

The toxic effects of irinotecan are well understood. Patients with genetic polymorphisms of the genes encoding for the enzyme UGT1A1 may have increased incidence of irinotecan-associated toxicities because of decreased clearance of the active metabolite SN38 via the glucuronidation pathway. To date, there have been limited publications describing systemic adverse events following TACE or DEBIRI-TACE and, based on a thorough literature search, none following these procedures in patients with UGT1A1 polymorphisms. Based on the scoring results of the Naranjo algorithm (7), we are confident in attributing the observed reaction to the patient's genetic polymorphism.

CONCLUSION

Although genetic testing prior to the initiation of irinotecan therapy is not currently recommended, assessment of UGT1A1 polymorphism is warranted when severe adverse events typical of systemic therapy manifest following DEBIRI-TACE.

Preemptive clinical pharmacogenetics implementation: current programs in five US medical centers

Although the field of pharmacogenetics has existed for decades, practioners have been slow to implement pharmacogenetic testing in clinical care. Numerous publications describe the barriers to clinical implementation of pharmacogenetics. Recently, several freely available resources have been developed to help address these barriers. In this review, we discuss current programs that use preemptive genotyping to optimize the pharmacotherapy of patients. Array-based preemptive testing includes a large number of relevant pharmacogenes that impact multiple high-risk drugs. Using a preemptive approach allows genotyping results to be available prior to any prescribing decision so that genomic variation may be considered as an inherent patient characteristic in the planning of therapy. This review describes the common elements among programs that have implemented preemptive genotyping and highlights key processes for implementation, including clinical decision support.

Implementation and utilization of genetic testing in personalized medicine

Clinical genetic testing began over 30 years ago with the availability of mutation detection for sickle cell disease diagnosis. Since then, the field has dramatically transformed to include gene sequencing, high-throughput targeted genotyping, prenatal mutation detection, preimplantation genetic diagnosis, population-based carrier screening, and now genome-wide analyses using microarrays and next-generation sequencing. Despite these significant advances in molecular technologies and testing capabilities, clinical genetics laboratories historically have been centered on mutation detection for Mendelian disorders. However, the ongoing identification of deoxyribonucleic acid (DNA) sequence variants associated with common diseases prompted the availability of testing for personal disease risk estimation, and created commercial opportunities for direct-to-consumer genetic testing companies that assay these variants. This germline genetic risk, in conjunction with other clinical, family, and demographic variables, are the key components of the personalized medicine paradigm, which aims to apply personal genomic and other relevant data into a patient’s clinical assessment to more precisely guide medical management. However, genetic testing for disease risk estimation is an ongoing topic of debate, largely due to inconsistencies in the results, concerns over clinical validity and utility, and the variable mode of delivery when returning genetic results to patients in the absence of traditional counseling. A related class of genetic testing with analogous issues of clinical utility and acceptance is pharmacogenetic testing, which interrogates sequence variants implicated in interindividual drug response variability. Although clinical pharmacogenetic testing has not previously been widely adopted, advances in rapid turnaround time genetic testing technology and the recent implementation of preemptive genotyping programs at selected medical centers suggest that personalized medicine through pharmacogenetics is now a reality. This review aims to summarize the current state of implementing genetic testing for personalized medicine, with an emphasis on clinical pharmacogenetic testing.

Prognostic advantage of irinotecan dose escalation according to uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) genotyping in patients with metastatic colorectal cancer treated with bevacizumab combined with 5-fluorouracil/leucovorin with irinotecan in a first-line setting

This study compared the clinical responses of patients with metastatic colorectal cancer (mCRC) with 5-fluorouracil/leucovorin with irinotecan (FOLFIRI) plus bevacizumab therapy either with or without uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) genotyping and irinotecan dose escalation. Of 107 total patients with mCRC, 79 were classified as the study group and 28 as the control group. The study group received irinotecan dose escalation based on UGT1A1 genotyping whereas the control group did not. Clinicopathologic features, response rates, and survival were compared for the 2 groups. The clinical response rate of patients with mCRC treated with FOLFIRI plus bevacizumab under UGT1A1 genotyping and irinotecan dose escalation was significantly better than that of those without these prospective tests and dose escalation (P = 0.028). Both progression-free survival (PFS) and overall survival were significantly greater in clinical responders than nonresponders (both, P < 0.001), and PFS was significantly greater among the study group patients than among the control group patients, with a median PFS of 12.2 months vs 9.4 months (P = 0.025). Grade 3/4 adverse events were not significantly different between the 2 groups (P = 0.189). Patients with mCRC undergoing UGT1A1 genotyping may receive escalated doses of irinotecan to obtain a better clinical response/outcome with comparable toxicities.

Hereditary colorectal cancer syndromes and genetic testing

Colorectal cancer (CRC) is a leading cause of cancer and cancer deaths in the Western world. Approximately 5-10% of CRC are hereditary, due to a defined genetic cause. Individuals and families affected with a hereditary CRC syndrome exhibit benign and malignant extra-intestinal tumors, require aggressive cancer screening and benefit from management by a multi-disciplinary team of professionals. The clinical manifestations, genetic causes and current management of patients with hereditary colon cancer syndrome is provided.

The use of the ‘linked evidence approach’ to guide policy on the reimbursement of personalized medicines

It is uncommon to find published clinical trials that measure the health benefits of medical testing. As a consequence, policy makers often have to decide whether access to, or public funding of, medical tests is warranted without knowing the clinical impact of testing on the patient. In the situation where a policy maker is considering a companion genetic test and tailored drug therapy, deficiencies in the evidence base are exacerbated because two technologies need to be assessed and the proposed genetic biomarker needs to be validated. The Linked Evidence Approach (LEA) is a methodology that was developed in 2005 to cope with inadequacies in the evidence supporting medical test evaluations. In 2010 the approach was adapted to the evaluation of pharmacogenetic interventions. This article describes how LEA and similar analytic frameworks are used internationally, highlights particular challenges with the approach, and proposes ways that LEA might be applied to pharmacogenomic interventions.

Pharmacogenovigilance: a pharmacogenomics pharmacovigilance program

In this report, we review the importance of pharmacovigilance in detecting postmarketing adverse drug events and the potential for developing pharmacogenovigilance programs by integrating pharmacogenomics with pharmacovigilance. We propose to start developing such a program in primary healthcare systems that use basic features of electronic medical records and have access to large numbers of patients commonly prescribed drugs. Such programs, if carefully designed, may grow over time and hopefully enhance the collection and interpretation of useful data for the clinical applications of pharmacogenomics testing.

Prioritizing genomic applications for action by level of evidence: a horizon-scanning method

As evidence accumulates on the use of genomic tests and other health-related applications of genomic technologies, decision makers may increasingly seek support in identifying which applications have sufficiently robust evidence to suggest they might be considered for action. As an interim working process to provide such support, we developed a horizon-scanning method that assigns genomic applications to tiers defined by availability of synthesized evidence. We illustrate an application of the method to pharmacogenomics tests.

Clinical implementation of germ line cancer pharmacogenetic variants during the next-generation sequencing era

More than 100 medications approved by the US Food and Drug Administration include pharmacogenetic biomarkers in the drug label, many with cancer indications referencing germ line DNA variations. With the advent of next-generation sequencing (NGS) and its rapidly increasing uptake into cancer research and clinical practice, an enormous amount of data to inform documented gene-drug associations will be collected that must be exploited to optimize patient benefit. This review focuses on the implementation of germ line cancer pharmacogenetics in clinical practice. Specifically, it discusses the importance of germ line variation in cancer and the role of NGS in pharmacogenetic discovery and implementation. In the context of a scenario in which massive amounts of NGS-based genetic information will be increasingly available to health stakeholders, this review explores the ongoing debate regarding the threshold of evidence necessary for implementation, provides an overview of recommendations in cancer by professional organizations and regulatory bodies, and discusses limitations of current guidelines and strategies to improve third-party coverage.

Toxicogenomics and cancer susceptibility: advances with next-generation sequencing

The aim of this review is to comprehensively summarize the recent achievements in the field of toxicogenomics and cancer research regarding genetic-environmental interactions in carcinogenesis and detection of genetic aberrations in cancer genomes by next-generation sequencing technology. Cancer is primarily a genetic disease in which genetic factors and environmental stimuli interact to cause genetic and epigenetic aberrations in human cells. Mutations in the germline act as either high-penetrance alleles that strongly increase the risk of cancer development, or as low-penetrance alleles that mildly change an individual's susceptibility to cancer. Somatic mutations, resulting from either DNA damage induced by exposure to environmental mutagens or from spontaneous errors in DNA replication or repair are involved in the development or progression of the cancer. Induced or spontaneous changes in the epigenome may also drive carcinogenesis. Advances in next-generation sequencing technology provide us opportunities to accurately, economically, and rapidly identify genetic variants, somatic mutations, gene expression profiles, and epigenetic alterations with single-base resolution. Whole genome sequencing, whole exome sequencing, and RNA sequencing of paired cancer and adjacent normal tissue present a comprehensive picture of the cancer genome. These new findings should benefit public health by providing insights in understanding cancer biology, and in improving cancer diagnosis and therapy.

Therapeutic targeting of CPT-11 induced diarrhea: a case for prophylaxis

CPT-11 (irinotecan), a DNA topoisomerase I inhibitor is one of the main treatments for colorectal cancer. The main dose limiting toxicities are neutropenia and late onset diarrhea. Though neutropenia is manageable, CPT-11 induced diarrhea is frequently severe, resulting in hospitalizations, dose reductions or omissions leading to ineffective treatment administration. Many potential agents have been tested in preclinical and clinical studies to prevent or ameliorate CPT-11 induced late onset diarrhea. It is predicted that prophylaxis of CPT-11 induced diarrhea will reduce sub-therapeutic dosing as well as hospitalizations and will eventually lead to dose escalations resulting in better response rates. This article reviews various experimental agents and strategies employed to prevent this debilitating toxicity. Covered topics include schedule/dose modification, intestinal alkalization, structural/chemical modification, genetic testing, anti-diarrheal therapies, transporter (ABCB1, ABCC2, BCRP2) inhibitors, enzyme (β-glucuronidase, UGT1A1, CYP3A4, carboxylesterase, COX-2) inducers and inhibitors, probiotics, antibiotics, adsorbing agents, cytokine and growth factor activators and inhibitors and other miscellaneous agents.