Comparison of oral capecitabine versus intravenous fluorouracil plus leucovorin as first-line treatment in 605 patients with metastatic colorectal cancer: results of a randomized phase III study

Overall survival with non-proportional hazards in first-line treatment for patients with metastatic colorectal cancer: Systematic review and network meta-analysis

This study aimed to identify the most effective first-line treatment for patients with metastatic colorectal cancer based on overall survival, identify the most commonly used treatment, and generate a meaningful ranking among all available treatments based on their relative effectiveness. Researchers used the ANOVA parametrization method to fit the second-order fractional polynomial network meta-analysis with a random-effect model. Using a non-proportional hazards network meta-analysis, 46 treatments were compared by considering a combination of direct and indirect evidence extracted from clinical trial studies. Included in the review were 46 trials involving 21350 patients. Between January 2000 and January 2023, researchers conducted a thorough search through Embase, PubMed/Medline, and Scopus. To undertake a secondary analysis of this data, we recreate individual patient data from published Kaplan-Meier (K-M) survival curves and assess the accuracy of that reconstruction. A random-effects model was used to evaluate the pooled overall survival and hazard ratio with a 95 percent confidence interval. The predicted survival curves for the network meta-analysis showed that GOLFIG and FOLFOX + Cetuximab treatments have higher survival, respectively. Our results provide moderate quality evidence and comparative effective estimates for various available first-line treatments for metastasis colorectal cancer based on network meta-analysis.

Discovering novel germline genetic variants linked to severe fluoropyrimidine-related toxicity in- and outside DPYD

BACKGROUND

The Alpe-DPD study (NCT02324452) demonstrated that prospective genotyping and dose-individualization using four alleles in DPYD (DPYD*2A/rs3918290, c.1236G > A/rs75017182, c.2846A > T/rs67376798 and c.1679 T > G/rs56038477) can mitigate the risk of severe fluoropyrimidine toxicity. However, this could not prevent all toxicities. The goal of this study was to identify additional genetic variants, both inside and outside DPYD, that may contribute to fluoropyrimidine toxicity.

METHODS

Biospecimens and data from the Alpe-DPD study were used. Exon sequencing was performed to identify risk variants inside DPYD. In silico and in vitro analyses were used to classify DPYD variants. A genome-wide association study (GWAS) with severe fluoropyrimidine-related toxicity was performed to identify variants outside DPYD. Association with severe toxicity was assessed using matched-pair analyses for the exon sequencing and logistic, Cox, and ordinal regression analyses for GWAS.

RESULTS

Twenty-four non-synonymous, frameshift, and splice site DPYD variants were detected in ten of 986 patients. Seven of these variants (c.1670C > T, c.1913 T > C, c.1925 T > C, c.506delC, c.731A > C, c.1740 + 1G > T, c.763 - 2A > G) were predicted to be deleterious. The carriers of either of these variants showed a trend towards a 2.14-fold (95% CI, 0.41-11.3, P = 0.388) increased risk of severe toxicity compared to matched controls (N = 30). After GWAS of 942 patients, no individual single nucleotide polymorphisms achieved genome-wide significance (P ≤ 5 × 10-8), however, five variants were suggestive of association (P < 5 × 10-6) with severe toxicity.

CONCLUSIONS

Results from DPYD exon sequencing and GWAS analysis did not identify additional genetic variants associated with severe toxicity, which suggests that testing for single markers at a population level currently has limited clinical value. Identifying additional variants on an individual level is still promising to explain fluoropyrimidine-related severe toxicity. In addition, studies with larger samples sizes, in more diverse cohorts are needed to identify potential clinically relevant genetic variants related to severe fluoropyrimidine toxicity.

DPYD genetic polymorphisms in non-European patients with severe fluoropyrimidine-related toxicity: a systematic review

BACKGROUND

Pre-treatment DPYD screening is mandated in the UK and EU to reduce the risk of severe and potentially fatal fluoropyrimidine-related toxicity. Four DPYD gene variants which are more prominently found in Europeans are tested.

METHODS

Our systematic review in patients of non-European ancestry followed PRISMA guidelines to identify relevant articles up to April 2023. Published in silico functional predictions and in vitro functional data were also extracted. We also undertook in silico prediction for all DPYD variants identified.

RESULTS

In 32 studies, published between 1998 and 2022, 53 DPYD variants were evaluated in patients from 12 countries encompassing 5 ethnic groups: African American, East Asian, Latin American, Middle Eastern, and South Asian. One of the 4 common European DPYD variants, c.1905+1G>A, is also present in South Asian, East Asian and Middle Eastern patients with severe fluoropyrimidine-related toxicity. There seems to be relatively strong evidence for the c.557A>G variant, which is found in individuals of African ancestry, but is not currently included in the UK genotyping panel.

CONCLUSION

Extending UK pre-treatment DPYD screening to include variants that are present in some non-European ancestry groups will improve patient safety and reduce race and health inequalities in ethnically diverse societies.

Two cases of metastatic colorectal cancer with prolonged liver injury following capecitabine combination chemotherapy

We present two cases of metastatic colorectal cancer where a liver injury developed while receiving capecitabine. In both cases, the patients were switched from oral capecitabine to a continuous intravenous 5-fluorouracil infusion and were able to continue treatment without a relapse of hepatotoxicity.

Prebiotic fibre mixtures counteract the manifestation of gut microbial dysbiosis induced by the chemotherapeutic 5-Fluorouracil (5-FU) in a validated in vitro model of the colon

BACKGROUND

5-Fluorouracil (5-FU) is used as an antineoplastic agent in distinct cancer types. Increasing evidence suggests that the gut microbiota might modulate 5-FU efficacy and toxicity, potentially affecting the patient's prognosis. The current experimental study investigated 5-FU-induced microbiota alterations, as well as the potential of prebiotic fibre mixtures (M1-M4) to counteract these shifts.

METHODS

A pooled microbial consortium was derived from ten healthy donors, inoculated in an in vitro model of the colon, and treated with 5-FU, with or without prebiotic fibre mixtures for 72 h. Four different prebiotic fibre mixtures were tested: M1 containing short-chain galacto-oligosaccharides (sc GOS), long-chain fructo-oligosaccharides (lcFOS), and low viscosity pectin (lvPect), M2 consisting of arabinoxylan, beta-glucan, pectin, and resistant starch, M3 which was a mixture of scGOS and lcFOS, and M4 containing arabinoxylan, beta-glucan, pectin, resistant starch, and inulin.

RESULTS

We identified 5-FU-induced changes in gut microbiota composition, but not in microbial diversity. Administration of prebiotic fibre mixtures during 5-FU influenced gut microbiota composition and taxa abundance. Amongst others, prebiotic fibre mixtures successfully stimulated potentially beneficial bacteria (Bifidobacterium, Lactobacillus, Anaerostipes, Weissella, Olsenella, Senegalimassilia) and suppressed the growth of potentially pathogenic bacteria (Klebsiella, Enterobacter) in the presence of 5-FU. The short-chain fatty acid (SCFA) acetate increased slightly during 5-FU, but even more during 5-FU with prebiotic fibre mixtures, while propionate was lower due to 5-FU with or without prebiotic fibre mixtures, compared to control. The SCFA butyrate and valerate did not show differences among all conditions. The branched-chain fatty acids (BCFA) iso-butyrate and iso-valerate were higher in 5-FU, but lower in 5-FU + prebiotics, compared to control.

CONCLUSIONS

These data suggest that prebiotic fibre mixtures represent a promising strategy to modulate 5-FU-induced microbial dysbiosis towards a more favourable microbiota, thereby possibly improving 5-FU efficacy and reducing toxicity, which should be evaluated further in clinical studies.

First-Line LV5FU2 with or without Aflibercept in Patients with Non-Resectable Metastatic Colorectal Cancer: A Randomized Phase II Trial (PRODIGE 25-FFCD-FOLFA)

Fluropyrimidine monotherapy is an option for some patients with inoperable metastatic colorectal cancer. Unlike bevacizumab, the addition of aflibercept, an antibody acting as an anti-angiogenic agent, has never been evaluated in this context. The aim of the study was to determine whether aflibercept could increase the efficacy of fluoropyrimidine monotherapy without increasing toxicity. This multicenter phase II non-comparative trial evaluated the addition of aflibercept to infusional 5-fluorouracil/folinic acid (LV5FU2 regimen) as first-line treatment in patients unfit to receive doublet cytotoxic chemotherapy. The primary endpoint was 6-month progression-free survival (PFS). The clinical hypotheses expected a PFS rate at 6 months of over 40% (60% expected). A total of 117 patients, with a median age of 81 years, were included: 59 in arm A (LV5FU2-aflibercept) and 58 in arm B (LV5FU2 alone). Six-month PFS was 54.7% in both arms (90% CI 42.5-66.5 in both). Median overall survival was 21.8 months (arm A) and 25.1 months (arm B). Overall toxicity was more common in arm A: grade ≥ 3 toxicity in 82% versus 58.2%. Given the 6-month PFS, the study can be considered positive. However, the toxicity of aflibercept in this population was high, and continuation of the trial into phase III is not envisaged.

Spotlight on capecitabine for the treatment of unresectable or metastatic carcinoma of various origin: A retrospective study of 25 dogs

Capecitabine, the oral prodrug of 5-fluorouracil, is indicated in people to treat various malignant epithelial cancers. In dogs, capecitabine has not been extensively evaluated. The aim of this retrospective study was to investigate toxicity and preliminary efficacy of single agent capecitabine in dogs with advanced malignant epithelial cancers of any site, for which no effective therapy existed, conventional treatment failed or was declined. Capecitabine was administered orally at 750 mg/m2 from day 1 to 14, followed by 1-week rest period, given as 3-week cycles. Safety evaluation was performed after 2 cycles, and every 2-3 cycles thereafter. Tumour response was determined every 2-3 cycles. Twenty-five dogs with hepatocellular carcinoma (n = 6), lung papillary carcinoma (n = 4), anal sac adenocarcinoma (n = 3), colic adenocarcinoma (n = 2), and other individually represented epithelial cancers (n = 10) were included. Dogs received a median of 4 cycles (range, 2-43) for a median of 84 days (range, 42-913). Toxicity occurred in 17 (68.0%) dogs; the most frequent adverse events were gastrointestinal, with the majority being self-resolving and of mild grade. Of the 22 dogs with macroscopic disease, 3 (13.6%) achieved partial remission, 16 (72.7%) were stable and 3 (13.6%) progressed; overall clinical benefit rate was 86.4%. Median progression-free interval was 93 days (95% CI 42-154; range, 1-521) and median tumour-specific survival was 273 days (95% CI 116-482; range 45-913). These findings suggest that capecitabine is an attractive option for the treatment of several types of carcinomas in dogs. Prospective studies are warranted to optimize the scheduling of capecitabine and confirm its efficacy.

A Nomogram to Predict Severe Toxicity in DPYD Wild-Type Patients Treated With Capecitabine-Based Anticancer Regimens

DPYD-guided dosing has improved the safety of fluoropyrimidine-based chemotherapy in recent years. However, severe toxicity remains in ~ 23% of patients not carrying DPYD variant alleles treated with capecitabine. Therefore, we developed a predictive model based on patient-related and treatment-related factors aimed at estimating the risk of developing severe capecitabine-related toxicity. The nomogram was developed using data from two large clinical trials (NCT00838370 and NCT02324452). Patients with cancer carrying a DPYD variant allele (DPYD*2A, c.1236G>A, c.2846A>T, and c.1679T>G) were excluded. Univariable and multivariable logistic regression using predetermined predictors based on previous findings, including age, sex, body surface area, type of treatment regimen, and creatinine levels were used to develop the nomogram. The developed model was internally validated using bootstrap resampling and cross-validation. This model was not externally or clinically validated. A total of 2,147 DPYD wild-type patients with cancer treated with capecitabine-based chemotherapy regimens were included of which complete data of 1,745 patients were available and used for the development of the nomogram. Univariable and multivariable logistic regression showed that age, sex, and type of treatment regimen were strong predictors of severe capecitabine-related toxicity in DPYD wild-type patients. Internal validation demonstrated a concordance index of 0.68 which indicates a good discriminative ability for prediction of severe capecitabine-related toxicity. The developed nomogram includes readily available parameters and may be a helpful tool for clinicians to assess the risk of developing severe capecitabine-related toxicity in patients without known risk DPYD variant alleles treated with capecitabine-based anticancer regimens.

TGF-β in correlation with tumor progression, immunosuppression and targeted therapy in colorectal cancer

Colorectal cancer (CRC) is a complex malignancy responsible for the second-highest cancer deaths worldwide. TGF-β maintains normal cellular homeostasis by inhibiting the cell cycle and inducing apoptosis, but its elevated level is correlated with colorectal cancer progression, as TGF-β is a master regulator of the epithelial-to-mesenchymal transition, a critical step of metastasis. Tumors, including CRC, use elevated TGF-β levels to avoid immune surveillance by modulating immune cell differentiation, proliferation, and effector function. Presently, the treatment of advanced CRC is mainly based on chemotherapy, with multiple adverse effects. Thus, there is a need to develop alternate tactics because CRC continue to be mostly resistant to the present therapeutic regimen. TGF-β blockade has emerged as a promising therapeutic target in cancer therapy. Blocking TGF-β with phytochemicals and other molecules, such as antisense oligonucleotides, monoclonal antibodies, and bifunctional traps, alone or in combination, may be a safer and more effective way to treat CRC. Furthermore, combination immunotherapy comprising TGF-β blockers and immune checkpoint inhibitors is gaining popularity because both molecules work synergistically to suppress the immune system. Here, we summarize the current understanding of TGF-β as a therapeutic target for managing CRC and its context-dependent tumor-promoting or tumor-suppressing nature.

Assessment of patients' knowledge of their treatment with capecitabine at the National Institute of Oncology in Rabat

INTRODUCTION

Capecitabine is a molecule of choice in the therapeutic arsenal of anticancer drugs used in Morocco for the treatment of breast cancer and colorectal cancer. Its frequent use imposes a follow-up and a post-prescription monitoring of the treatment modalities as well as the adverse events that may occur following its administration.

OBJECTIVE

The objective of this study is to evaluate the level of knowledge of patients in the day hospital of an oncology facility about their treatment with capecitabine.

MATERIALS AND METHODS

This is a prospective study conducted over a period of 2 months (January-February 2022) at the day hospital in the National Institute of Oncology in Rabat, and it was conducted using a questionnaire in order to evaluate patients' knowledge about their treatment with capecitabine.

RESULTS

This study involved 95 patients, 76% claimed to have ever received pharmaceutical advice on capecitabine treatment. The main indications were colorectal and breast cancer. Ninety seven percent knew the indication for capecitabine and the action of the molecule on the relevant tumor. Eighty three percent receiving capecitabine therapy reported the occurrence of side effects and hand-foot syndrome was the most reported in 31.2% of the total listed side effects.

DISCUSSION

Capecitabine is an oral treatment of choice for colorectal and breast cancer in Morocco. Therapeutic education happens to be an effective tool in order to guarantee the best effectiveness and manage the possible side effects that can occur during the treatment.

Implementation of upfront DPYD genotyping with a low-cost and high-throughput assay to guide fluoropyrimidine treatment in cancer patients

OBJECTIVES

Genetic variants in the dihydropyrimidine dehydrogenase (DPYD ) gene are associated with reduced dihydropyrimidine dehydrogenase enzyme activity and can cause severe fluoropyrimidine-related toxicity. We assessed the frequency of the four most common and well-established DPYD variants associated with fluoropyrimidine toxicity and implemented a relatively low-cost and high-throughput genotyping assay for their detection.

METHODS

This study includes 457 patients that were genotyped for the DPYD c.1129-5923C>G, c.1679T>G, c.1905 + 1G>A and c.2846A>T variants, either by Sanger sequencing or kompetitive allele specific PCR (KASP) technology. Of these, 172 patients presented toxicity during treatment with fluoropyrimidines (post-treatment group), and 285 were tested before treatment (pretreatment group).

RESULTS

Heterozygous DPYD variants were identified in 7.4% of the entire series of 457 patients, being the c.2846A>T the most frequent variant. In the post-treatment group, 15.7% of the patients presented DPYD variants, whereas only 2.5% of the patients in the pretreatment group presented a variant. The KASP assays designed in this study presented 100% genotype concordance with the results obtained by Sanger sequencing.

CONCLUSIONS

The combined assessment of the four DPYD variants in our population increases the identification of patients at high risk for developing fluoropyrimidine toxicity, supporting the upfront routine implementation of DPYD variant genotyping. Furthermore, the KASP genotyping assay described in this study presents a rapid turnaround time and relatively low cost, making upfront DPYD screening feasible in clinical practice.

Implementation of pharmacogenetic testing in oncology: DPYD-guided dosing to prevent fluoropyrimidine toxicity in British Columbia

Background: Fluoropyrimidine toxicity is often due to variations in the gene (DPYD) encoding dihydropyrimidine dehydrogenase (DPD). DPYD genotyping can be used to adjust doses to reduce the likelihood of fluoropyrimidine toxicity while maintaining therapeutically effective drug levels. Methods: A multiplex QPCR assay was locally developed to allow genotyping for six DPYD variants. The test was offered prospectively for all patients starting on fluoropyrimidines at the BC Cancer Centre in Vancouver and then across B.C., Canada as well as retrospectively for patients suspected to have had an adverse reaction to therapy. Dose adjustments were made for variant carriers. The incidence of toxicity in the first three cycles was compared between DPYD variant allele carriers and non-variant carriers. Subsequent to an initial implementation phase, this test was made available province-wide. Results: In 9 months, 186 patients were tested and 14 were found to be heterozygous variant carriers. Fluoropyrimidine-related toxicity was higher in DPYD variant carriers. Of 127 non-variant carriers who have completed chemotherapy, 18 (14%) experienced severe (grade ≥3, Common Terminology Criteria for Adverse Events version 5.0). Of note, 22% (3 patients) of the variant carriers experienced severe toxicity even after DPYD-guided dose reductions. For one of these carriers who experienced severe thrombocytopenia within the first week, DPYD testing likely prevented lethal toxicity. In DPYD variant carriers who tolerate reduced doses, a later 25% increase led to chemotherapy discontinuation. As a result, a recommendation was made to clinicians based on available literature and expert opinion specifying that variant carriers who tolerated two cycles without toxicity can have a dose escalation of only 10%. Conclusion: DPYD-guided dose reductions were a feasible and acceptable method of preventing severe toxicity in DPYD variant carriers. Even with dose reductions, there were variant carriers who still experienced severe fluoropyrimidine toxicity, highlighting the importance of adhering to guideline-recommended dose reductions. Following the completion of the pilot phase of this study, DPYD genotyping was made available province-wide in British Columbia.

Budget impact and transferability of cost-effectiveness of DPYD testing in metastatic breast cancer in three health systems

The cost-effectiveness and budget impact of introducing extended DPYD testing prior to fluoropyrimidine-based chemotherapy in metastatic breast cancer patients in the UK, The Netherlands and Hungary were examined. DPYD testing with ToxNav© was cost-effective in all three countries. In the UK and The Netherlands, the ToxNav strategy led to more quality-adjusted life years and fewer costs to the health systems compared with no genetic testing and standard dosing of capecitabine/5-fluorouracil. In Hungary, the ToxNav strategy produced more quality-adjusted life years at a higher cost compared with no testing and standard dose. The ToxNav strategy was found to offer budget savings in the UK and in The Netherlands, while in Hungary it resulted in additional budget costs.

Cost-effectiveness of extended DPYD testing before fluoropyrimidine chemotherapy in metastatic breast cancer in the UK

The aim of this study was to evaluate the cost-effectiveness of ToxNav©, a multivariant genetic test, to screen for DPYD followed by personalized chemotherapy dosing for metastatic breast cancer in the UK compared with no testing followed by standard dose, standard of care. In the main analysis, ToxNav was dominant over standard of care, producing 0.19 additional quality-adjusted life years and savings of £78,000 per patient over a lifetime. The mean additional quality-adjusted life years per person from 1000 simulations was 0.23 savings (95% CI: 0.22-0.24) at £99,000 (95% CI: £95-102,000). Varying input parameters independently by range of 20% was unlikely to change the results in the main analysis. The probabilistic sensitivity analysis showed ~97% probability of the ToxNav strategy to be dominant.

Commonly prescribed medications associated with alopecia

BACKGROUND

The diagnosis and treatment of medication-associated alopecia often challenges patients and physicians. While numerous studies on the topic exist, limited information on the strength and magnitude of these studies exists.

OBJECTIVES

We investigated the most commonly prescribed medications with high levels of evidence to support associations with alopecia.

METHODS

A list of most commonly prescribed medications was compiled using the "Top 100 Prescriptions, Sales" (Intercontinental Marketing Services) and "Top 200 Names Searched" (RxList.com). PubMed, Embase, and Web of Science were searched for "generic drug name" AND "alopecia" and "generic drug name" AND "hair loss." Two reviewers independently reviewed articles for drug, study type and level of evidence, and number of alopecia cases.

RESULTS

A total of 192 unique drugs were investigated, with 110 yielding positive search results. Of these, 13 were associated with alopecia in studies with strong levels of evidence (adalimumab, infliximab, budesonide, interferon β-1α, tacrolimus, enoxaparin, zoster vaccine, lamotrigine, docetaxel, capecitabine, erlotinib, imatinib, and bortezomib).

LIMITATIONS

Only full-length articles available in the English language were included. The methodology used relied on lists of drugs based on their sales rather than number of prescriptions, which likely overrepresented expensive drugs.

CONCLUSIONS

Few studies with high levels of evidence have been conducted on the topic of medication-associated alopecia. The mechanisms of hair loss must be further identified to provide effective management.

Diatom-Based Nanomedicine for Colorectal Cancer Treatment: New Approaches for Old Challenges

Colorectal cancer is among the most prevalent and lethal cancers globally. To address this emergency, countries have developed diffuse screening programs and innovative surgical techniques with a consequent decrease in mortality rates in non-metastatic patients. However, five years after diagnosis, metastatic CRC is still characterized by less than 20% survival. Most patients with metastatic CRC cannot be surgically treated. For them, the only option is treatment with conventional chemotherapies, which cause harmful side effects in normal tissues. In this context, nanomedicine can help traditional medicine overcome its limits. Diatomite nanoparticles (DNPs) are innovative nano-based drug delivery systems derived from the powder of diatom shells. Diatomite is a porous biosilica largely found in many areas of the world and approved by the Food and Drug Administration (FDA) for pharmaceutical and animal feed formulations. Diatomite nanoparticles with a size between 300 and 400 nm were shown to be biocompatible nanocarriers capable of delivering chemotherapeutic agents against specific targets while reducing off-target effects. This review discusses the treatment of colorectal cancer with conventional methods, highlighting the drawbacks of standard medicine and exploring innovative options based on the use of diatomite-based drug delivery systems. Three targeted treatments are considered: anti-angiogenetic drugs, antimetastatic drugs, and immune checkpoint inhibitors.

Dihydropyrimidine dehydrogenase phenotype in peripheral blood mononuclear cells is related to adverse events of fluoropyrimidine-therapy

PURPOSE

The primary objective of this study was to determine if dihydropyrimidine dehydrogenase (DPD) activity measured in peripheral blood mononuclear cells (PBMCs) is related to adverse events during fluoropyrimidine therapy.

METHODS

A retrospective cohort study was conducted. The study population included 481 patients who received fluoropyrimidine treatment and for whom relevant patient characteristics were known and adverse events were noted in the electronic health records. Factors besides DPD phenotype that could affect the incidence of adverse events were corrected for using log regression. These log regression models were used to identify an association between the DPD phenotype measured in PBMCs and adverse events.

RESULTS

Patients with a decreased DPD activity measured in PBMCs suffered more adverse events. Results from log regression data show that this effect remains significant after correcting for dosage, chemotherapy regimen and relevant patient characteristics.

CONCLUSION

A significant correlation was found between reduced DPD enzyme activity in PBMCs and adverse events. The findings in this paper support further exploring DPD phenotyping as a method for preventing fluoropyrimidine-related adverse events. Further assessment of DPD phenotyping will require clinical validation in a prospective study.

Implementation of dihydropyrimidine dehydrogenase deficiency testing in Europe

BACKGROUND

The main cause for fluoropyrimidine-related toxicity is deficiency of the metabolizing enzyme dihydropyrimidine dehydrogenase (DPD). In 2020, the European Medicines Agency (EMA) recommended two methods for pre-treatment DPD deficiency testing in clinical practice: phenotyping using endogenous uracil concentration or genotyping for DPYD risk variant alleles. This study assessed the DPD testing implementation status in Europe before (2019) and after (2021) the release of the EMA recommendations.

METHODS

The survey was conducted from 16 March 2022 to 31 July 2022. An electronic form with seven closed and three open questions was e-mailed to 251 professionals with DPD testing expertise of 34 European countries. A descriptive analysis was conducted.

RESULTS

We received 79 responses (31%) from 23 countries. Following publication of the EMA recommendations, 87% and 75% of the countries reported an increase in the amount of genotype and phenotype testing, respectively. Implementation of novel local guidelines was reported by 21 responders (27%). Countries reporting reimbursement of both tests increased in 2021, and only four (18%) countries reported no coverage for any testing type. In 2019, major implementation drivers were 'retrospective assessment of fluoropyrimidine-related toxicity' (39%), and in 2021, testing was driven by 'publication of guidelines' (40%). Although the major hurdles remained the same after EMA recommendations-'lack of reimbursement' (26%; 2019 versus 15%; 2021) and 'lack of recognizing the clinical relevance by medical oncologists' (25%; 2019 versus 8%; 2021)-the percentage of specialists citing these decreased. Following EMA recommendations, 25% of responders reported no hurdles at all in the adoption of the new testing practice in the clinics.

CONCLUSIONS

The EMA recommendations have supported the implementation of DPD deficiency testing in Europe. Key factors for successful implementation were test reimbursement and clear clinical guidelines. Further efforts to improve the oncologists' awareness of the clinical relevance of DPD testing in clinical practice are needed.

Redefining the Incidence and Profile of Fluoropyrimidine-Associated Cardiotoxicity in Cancer Patients: A Systematic Review and Meta-Analysis

Aim: The cardiac toxicity that occurs during administration of anti-tumor agents has attracted increasing concern. Fluoropyrimidines have been used for more than half a century, but their cardiotoxicity has not been well clarified. In this study, we aimed to assess the incidence and profile of fluoropyrimidine-associated cardiotoxicity (FAC) comprehensively based on literature data. Methods: A systematic literature search was performed using PubMed, Embase, Medline, Web of Science, and Cochrane library databases and clinical trials on studies investigating FAC. The main outcome was a pooled incidence of FAC, and the secondary outcome was specific treatment-related cardiac AEs. Random or fixed effects modeling was used for pooled meta-analyses according to the heterogeneity assessment. PROSPERO registration number: (CRD42021282155). Results: A total of 211 studies involving 63,186 patients were included, covering 31 countries or regions in the world. The pooled incidence of FAC, by meta-analytic, was 5.04% for all grades and 1.5% for grade 3 or higher. A total of 0.29% of patients died due to severe cardiotoxicities. More than 38 cardiac AEs were identified, with cardiac ischemia (2.24%) and arrhythmia (1.85%) being the most frequent. We further performed the subgroup analyses and meta-regression to explore the source of heterogeneity, and compare the cardiotoxicity among different study-level characteristics, finding that the incidence of FAC varied significantly among different publication decades, country/regions, and genders. Patients with esophagus cancer had the highest risk of FAC (10.53%), while breast cancer patients had the lowest (3.66%). The treatment attribute, regimen, and dosage were significantly related to FAC. When compared with chemotherapeutic drugs or targeted agents, such a risk was remarkably increased (χ2 = 10.15, p < 0.01; χ2 = 10.77, p < 0.01). The continuous 5-FU infusion for 3–5 consecutive days with a high dosage produced the highest FAC incidence (7.3%) compared with other low-dose administration patterns. Conclusions: Our study provides comprehensive global data on the incidence and profile of FAC. Different cancer types and treatment appear to have varying cardiotoxicities. Combination therapy, high cumulative dose, addition of anthracyclines, and pre-existing heart disease potentially increase the risk of FAC.

Assay performance and stability of uracil and dihydrouracil in clinical practice

PURPOSE

Measurement of endogenous uracil (U) is increasingly being used as a dose-individualization method in the treatment of cancer patients with fluoropyrimidines. However, instability at room temperature (RT) and improper sample handling may cause falsely increased U levels. Therefore we aimed to study the stability of U and dihydrouracil (DHU) to ensure proper handling conditions.

METHODS

Stability of U and DHU in whole blood, serum, and plasma at RT (up to 24 h) and long-term stability (≥ 7 days) at - 20 °C were studied in samples from 6 healthy individuals. U and DHU levels of patients were compared using standard serum tubes (SSTs) and rapid serum tubes (RSTs). The performance of our validated UPLC-MS/MS assay was assessed over a period of 7 months.

RESULTS

U and DHU levels significantly increased at RT in whole blood and serum after blood sampling with increases of 12.7 and 47.6% after 2 h, respectively. A significant difference (p = 0.0036) in U and DHU levels in serum was found between SSTs and RSTs. U and DHU were stable at - 20 °C at least 2 months in serum and 3 weeks in plasma. Assay performance assessment fulfilled the acceptance criteria for system suitability, calibration standards, and quality controls.

CONCLUSION

A maximum of 1 h at RT between sampling and processing is recommended to ensure reliable U and DHU results. Assay performance tests showed that our UPLC-MS/MS method was robust and reliable. Additionally, we provided a guideline for proper sample handling, processing and reliable quantification of U and DHU.

Implementation and clinical benefit of DPYD genotyping in a Danish cancer population

BACKGROUND

In 2020, the European Medicines Agency recommended testing patients for dihydropyrimidine dehydrogenase (DPD) deficiency before systemic treatment with fluoropyrimidines (FP). DPD activity testing identifies patients at elevated risk of severe FP-related toxicity (FP-TOX). The two most used methods for DPD testing are DPYD genotyping and DPD phenotyping (plasma uracil concentration). The primary objective of this study was to compare the overall frequency of overall grade ≥3 FP-TOX before and after the implementation of DPYD genotyping.

PATIENTS AND METHODS

Two hundred thirty Danish, primarily gastrointestinal cancer patients, were DPYD-genotyped before their first dose of FP, and blood was sampled for post hoc assessment of P-uracil. The initial dose was reduced for variant carriers. Grade ≥3 FP-TOX was registered after the first three treatment cycles of FP. The frequency of toxicity was compared to a historical cohort of 492 patients with post hoc determined DPYD genotype from a biobank.

RESULTS

The frequency of overall grade ≥3 FP-TOX was 27% in the DPYD genotype-guided group compared to 24% in the historical cohort. In DPYD variant carriers, DPYD genotyping reduced the frequency of FP-related hospitalization from 19% to 0%. In the control group, 4.8% of DPYD variant carriers died due to FP-TOX compared to 0% in the group receiving DPYD genotype-guided dosing of FP. In the intervention group, wild-type patients with uracil ≥16 ng/ml had a higher frequency of FP-TOX than wild-type patients with uracil <16 ng/ml (55% versus 28%).

CONCLUSIONS

We found no population-level benefit of DPYD genotyping when comparing the risk of grade ≥3 FP-TOX before and after clinical implementation. We observed no deaths or FP-related hospitalizations in patients whose FP treatment was guided by a variant DPYD genotype. The use of DPD phenotyping may add valuable information in DPYD wild-type patients.

In vitro co-culture systems of hepatic and intestinal cells for cellular pharmacokinetic and pharmacodynamic studies of capecitabine against colorectal cancer

BACKGROUND

As a prodrug of 5-fluorouracil (5-FU), orally administrated capecitabine (CAP) undergoes preliminary conversion into active metabolites in the liver and then releases 5-FU in the gut to exert the anti-tumor activity. Since metabolic changes of CAP play a key role in its activation, a single kind of intestinal or hepatic cell can never be used in vitro to evaluate the pharmacokinetics (PK) and pharmacodynamics (PD) nature. Hence, we aimed to establish a novel in vitro system to effectively assess the PK and PD of these kinds of prodrugs.

METHODS

Co-culture cellular models were established by simultaneously using colorectal cancer (CRC) and hepatocarcinoma cell lines in one system. Cell Counting Kit-8 (CCK-8) and flow cytometric analysis were used to evaluate cell viability and apoptosis, respectively. Apoptosis-related protein expression levels were measured using western blot analysis. A selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for cellular PK in co-culture models.

RESULTS

CAP had little anti-proliferative effect on the five monolayer CRC cell lines (SW480, LoVo, HCT-8, HCT-116 and SW620) or the hepatocarcinoma cell line (HepG2). However, CAP exerted marked anti-tumor activities on each of the CRC cell lines in the co-culture models containing both CRC and hepatocarcinoma cell lines, although its effect on the five CRC cell lines varied. Moreover, after pre-incubation of CAP with HepG2 cells, the culture media containing the active metabolites of CAP also showed an anti-tumor effect on the five CRC cell lines, indicating the crucial role of hepatic cells in the activation of CAP.

CONCLUSION

The simple and cost‑effective co-culture models with both CRC and hepatocarcinoma cells could mimic the in vivo process of a prodrug dependent on metabolic conversion to active metabolites in the liver, providing a valuable strategy for evaluating the PK and PD characteristics of CAP-like prodrugs in vitro at the early stage of drug development.

Renal impairment and abnormal liver function tests in pre-therapeutic phenotype-based DPD deficiency screening using uracilemia: a comprehensive population-based study in 1138 patients

Background

Dihydropyrimidine dehydrogenase (DPD) deficiency screening is a pre-therapeutic standard to prevent severe fluoropyrimidine-related toxicity. Although several screening methods exist, the accuracy of their results remains debatable. In France, the uracilemia measurement is considered the standard in DPD deficiency screening. The objective of this study was to describe the hyperuracilemia (⩾16 ng/mL) rate and investigate the influence of hepatic and renal impairment in uracilemia measurements since the guidelines were implemented.

Patients and methods

Using a cohort of 1138 patients screened between 18 October 2018 and 18 October 2021, basic demographic characteristics, date of blood sampling, and potential biological confounders including liver function tests [aspartate aminotransaminase (AST), alanine aminotransaminase (ALT), gamma-glutamyl transferase (γGT), alkaline phosphatase (ALP), and bilirubin] and estimated glomerular filtration rate (eGFR) were collected. The second same-patient uracilemia analysis was also performed. Temporal change was graphically represented while potential confounders were stratified to show linearity when suspected.

Results

Hyperuracilemia was diagnosed in 12.7% (n = 150) samples with 6.7%, 5.4%, 0.5%, and 0.08% between 16 and 20 ng/mL, 20 and 50 ng/mL, 50 and 150 ng/mL, and >150 ng/mL, respectively. The median uracilemia concentration was 9.4 ng/mL (range: 1.2 and 172.3 ng/mL) and the monthly hyperuracilemia rate decreased steadily from >30% to around 9%. Older age, normalized AST, γGT, ALP results, bilirubin levels, and decreased eGFR were linearly associated with higher plasma uracil concentrations (all p < 0.001). In the adjusted multivariate linear model, AST, eGFR, and ALP remained associated with uracilemia (p < 0.05). When measured twice in 39 patients, the median uracilemia rate of change was -2.5%, which subsequently changed the diagnosis in nine patients (23.1%).

Conclusions

Better respect of pre-analytical conditions may explain the steady decrease in monthly hyperuracilemia rates over the 3 years. Elevated AST, ALP levels, and reduced eGFR could induce a false increase in uracilemia and second uracilemia measurements modified the first DPD deficiency diagnosis in almost 25% of the patients.

An Overview of Clinical Trials in the Treatment of Resectable Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-related death worldwide. Partial hepatectomy, one of a few curative therapeutic modalities, is plagued by high recurrence rate of up to 70% at 5 years. Throughout the past 3 decades, many clinical trials have attempted to improve HCC recurrence rate following partial hepatectomy using adjuvant and neoadjuvant treatment modalities such as antiviral therapy, brachytherapy, systemic chemotherapy, immunotherapy, transarterial chemoembolization and radioembolization, and radiotherapy. The goal of this review is to discuss the clinical trials pertaining to resectable HCC including surgical technique considerations, adjuvant, and neoadjuvant treatment modalities.

Patient-Derived Organoids for In Vivo Validation of In Vitro Data

Patient-derived organoids are promising tumor models for functional validation of next-generation sequencing-based therapy recommendations. In times of rapidly advancing precision oncology approaches in everyday clinical processes, reliable and valid tumor models are required. Tumor organoids consist of tumor "stem" cells, differentiated (epithelial) tumor, and stroma cells. The cellular architecture and interactions closely mimic the original patient tumor. These organoids can be implanted into immunodeficient mice, generating patient-derived organoid-derived xenografts, thus enabling in vitro to in vivo transfer. Most importantly, the high clinical relevance of PDO models is maintained in this conversion. This protocol describes in detail the methods and techniques as well as the materials necessary to generate in vitro PDO and in vivo PDO-derived xenograft models. The elaborate process description starts with the processing of freshly obtained tumor tissue. The proceedings include tissue processing, organoid culturing, PDO implantation into immunodeficient mice, tumor explantation, and finally tumor preservation. All these proceedings are described in this timely chronological order. This protocol will enable researchers to generate PDO models from freshly received tumor tissue and generate PDO-derived xenografts. Models generated according to these methods are suitable for a very broad research spectrum.

Fluoropyrimidine‑induced cardiotoxicity in colorectal cancer patients: a prospective observational trial (CHECKPOINT)

Fluoropyrimidines (FP) are the backbone chemotherapy in colorectal cancer (CRC) treatment; however, their use is associated with cardiotoxicity, which is underreported. In the present study, it was aimed to prospectively determine the incidence rates and related risk factors of FP‑induced cardiotoxicity (FIC) in CRC patients and at identifying predictive biomarkers. A total of 129 consecutive previously untreated CRC patients underwent active cardiological monitoring, including 5‑items simplified questionnaire on symptoms, electrocardiogram (ECG) and plasma sample collection during FP chemotherapy. FIC was defined as the presence of ECG alterations and/or the arising of at least one symptom of chest pain, dyspnoea, palpitations or syncope. The primary objective was the evaluation of FIC incidence. Secondary objectives were the correlation of FIC with well‑known cardiological risk factors and the identification of circulating biomarkers (serum levels of troponin I, pro hormone BNP; miRNA analysis) as predictors of FIC. A total of 20 out of 129 (15.5%) patients experienced FIC. The most common symptoms were dyspnoea (60%) and chest pain (40%), while only 15% of patients presented ECG alterations, including one acute myocardial infarction. Retreatment with FP was attempted in 90% of patients with a favourable outcome. Despite 48% of patients having cardiological comorbidities, an increased FIC was not observed in this subgroup. Only the subgroup of females with the habit of alcohol consumption showed an increased risk of FIC. None of the circulating biomarkers evaluated demonstrated a clinical utility as FIC predictors. FIC can be an unexpected, life‑threatening adverse event that can limit the subsequent treatment choices in patients with CRC. In this prospective study, well‑known cardiological comorbidities were not related to higher FIC risk and circulating biomarkers predictive of toxicity could not be found. With careful monitoring, mainly based on symptoms, almost all patients completed the FP treatment.

Curcumin: A Novel Way to Improve Quality of Life for Colorectal Cancer Patients?

Colorectal cancer (CRC) is the third most common cancer in men and the second most common in women. Treatment of metastatic CRC consists of highly toxic chemotherapeutic drug combinations that often negatively affect patient quality of life (QoL). Moreover, chemotherapy-induced toxicity and chemotherapy resistance are among the most important factors limiting cancer treatment and can lead to the interruption or discontinuation of potentially effective therapy. Several preclinical studies have demonstrated that curcumin acts through multiple cellular pathways and possesses both anti-cancer properties against CRC and the capacity to mitigate chemotherapy-related side effects and overcome drug resistance. In this review article, we suggest that the addition of curcumin to the standard chemotherapeutic treatment for metastatic CRC could reduce associated side-effects and overcome chemotherapy resistance, thereby improving patient QoL.

Identification of BGN and THBS2 as metastasis-specific biomarkers and poor survival key regulators in human colon cancer by integrated analysis

BACKGROUND

Colon cancer is the second leading cause of death worldwide. Exploring key regulators in colon cancer metastatic progression could lead to better outcomes for patients.

METHODS

Initially, the transcriptional profiles of 681 colonrectal cancer (CRC) cases were used to discover signature genes that were significantly correlated with colon cancer metastasis. These signature genes were then validated using another independent 210 CRC cases' transcriptomics and proteomics profiles, and Kaplan-Meier regression analyses were used to screen the key regulators with patients' survival. Immunohistochemical staining was used to confirm the biomarkers, and transit knockdown was used to explore their implications on colon cancer cells migration and invasion abilities. The impact on the key signalling molecules in epithelial-mesenchymal transition (EMT) process that drive tumour metastasis was tested using Western blot. The response to clinical standard therapeutic drugs was compared to clinical prognosis of key regulators using an ROC plotter.

RESULTS

Five genes (BGN, THBS2, SPARC, CDH11 and SPP1) were initially identified as potential biomarkers and therapeutic targets of colon cancer metastasis. The most significant signatures associated with colon cancer metastasis were determined to be BGN and THBS2. Furthermore, highly expression of BGN and THBS2 in tumours was linked to a worse survival rate. BGN and THBS2 knockdown significantly reduced colon cancer cells migration and invasion, as well as down-regulating three EMT-related proteins (Snail, Vimentin and N-cadherin), and increasing the proliferation inhibitory effect of 5-fluorouracil, irinotecan and oxaliplatin treatment.

CONCLUSIONS

CRC metastatic progression, EMT phenotypic transition and poor survival time have been linked to BGN and THBS2. They could be utilized as potential diagnostic and therapeutic targets for colon cancer metastatic patients with a better prognosis.

DPYD genotyping and dihydropyrimidine dehydrogenase (DPD) phenotyping in clinical oncology. A clinically focused minireview

BACKGROUND

In clinical oncology, systemic 5-fluorouracil (5-FU) and its oral pro-drugs are used to treat a broad group of solid tumours. Patients with dihydropyrimidine dehydrogenase (DPD) enzyme deficiency are at elevated risk of toxicity if treated with standard doses of 5-FU. DPYD genotyping and measurements of plasma uracil concentration (DPD phenotyping) can be applied as tests for DPD deficiency. In April 2020, the European Medicines Agency recommended pre-treatment DPD testing to reduce the risk of 5-FU-related toxicity.

OBJECTIVES

The objective of this study is to present the current evidence for DPD testing in routine oncological practice.

METHODS

Two systematic literature searches were performed following the PRISMA guidelines. We identified studies examining the possible benefit of DPYD genotyping or DPD phenotyping on the toxicity risk.

FINDINGS

Nine and 12 studies met the criteria for using DPYD genotyping and DPD phenotyping, respectively.

CONCLUSIONS

The evidence supporting either DPYD genotyping or DPD phenotyping as pre-treatment tests to reduce 5-FU toxicity is poor. Further evidence is still needed to fully understand and guide clinicians to dose by DPD activity.

Genotype-based chemotherapy for patients with gastrointestinal tumors: focus on oxaliplatin, irinotecan, and fluoropyrimidines

This review aimed to summarize the pharmacogenetic studies of the most commonly used drugs in the chemotherapy of gastrointestinal (GI) tumors: oxaliplatin, irinotecan, and fluoropyrimidines. So far, it has not been possible to develop an effective genotype-based approach for oxaliplatin. More and more evidence is emerging in favor of the fact that the choice of a dose of fluorouracil based on pharmacogenetic testing according to DPYD*2A, can be not only effective but also cost-effective. Additional, well-planned trials of the UGT1A1 genotype-based approach to irinotecan therapy are predicted to reduce adverse drug events in people with the UGT1A1*28/*28 genotypes and improve treatment efficacy in the rest of the patients, which might be cost-effective.

Safety and efficacy of irinotecan, oxaliplatin, and capecitabine (XELOXIRI) regimen with or without targeted drugs in patients with metastatic colorectal cancer: a retrospective cohort study

BACKGROUND

Five-fluorouracil, folinic acid, oxaliplatin and irinotecan (FOLFOXIRI) regimen is used as the first-line treatment for metastatic colorectal cancer (mCRC). The use of capecitabine, an oral fluoropyrimidine pro-drug, is feasible and safe; hence, it provides an interesting alternative to 5-fluorouracil in the abovementioned regimen. This study aimed to evaluate the efficacy and safety of capecitabine, oxaliplatin, and irinotecan (XELOXIRI) regimen use with or without targeted drugs in Chinese patients with mCRC.

METHODS

We conducted a retrospective, longitudinal cohort study of patients with mCRC who received XELOXIRI regimen with or without targeted drugs (bevacizumab or cetuximab) every 2 weeks between January 2017 and November 2019 at the National Cancer Center/Cancer Hospital, the Chinese Academy of Medical Sciences, and Peking Union Medical College. Treatment efficacy was assessed by investigators by evaluating the objective response rate (ORR) and disease control rate (DCR). Overall survival (OS) was assessed using Cox proportional hazards models. The adverse events were also analyzed.

RESULTS

Sixty-one consecutive patients were examined and followed up for survival. As of November 8, 2021, the median follow-up time was 35.4 months. Disease progression and death occurred in 50 (82%) and 38 (62%) patients, respectively. The median treatment duration of XELOXIRI with or without bevacizumab or cetuximab was 10 cycles (range, 1-12 cycles). The median OS and PFS were 32.2 months (95%CI [24.8-39.6]) and 9.3 months (95% CI [8.1-10.5]), respectively. The ORR of 48 patients with measurable lesions was 70.8%, and the DCR was 89.6%. RAS/BRAF wild-type (HR 0.39; 95% CI [0.16-0.96], p = 0.04) and metastatic organs > 2 (HR 3.25; 95% CI [1.34-7.87], p = 0.009) were independent prognostic factors for OS. The incidence of any grade of adverse events (AEs) was 96.7% (59/61). Grade ≥ 3 AEs included neutropenia (19.7%), leukopenia (9.8%), diarrhea (3.3%), vomiting (3.3%), febrile neutropenia (1.6%), and thrombocytopenia (1.6%). No treatment-related death occurred.

CONCLUSION

The use of the XELOXIRI regimen with or without a targeted drug was effective, with a manageable toxicity profile in Chinese patients with mCRC.

Dihydropyrimidine Dehydrogenase Phenotyping Using Pretreatment Uracil: A Note of Caution Based on a Large Prospective Clinical Study

In clinical practice, 25-30% of the patients treated with fluoropyrimidines experience severe fluoropyrimidine-related toxicity. Extensively clinically validated DPYD genotyping tests are available to identify patients at risk of severe toxicity due to decreased activity of dihydropyrimidine dehydrogenase (DPD), the rate limiting enzyme in fluoropyrimidine metabolism. In April 2020, the European Medicines Agency recommended that, as an alternative for DPYD genotype-based testing for DPD deficiency, also phenotype testing based on pretreatment plasma uracil levels is a suitable method to identify patients with DPD deficiency. Although the evidence for genotype-directed dosing of fluoropyrimidines is substantial, the level of evidence supporting plasma uracil levels to predict DPD activity in clinical practice is limited. Notwithstanding this, uracil-based phenotyping is now used in clinical practice in various countries in Europe. We aimed to determine the value of pretreatment uracil levels in predicting DPD deficiency and severe treatment-related toxicity. To this end, we determined pretreatment uracil levels in 955 patients with cancer, and assessed the correlation with DPD activity in peripheral blood mononuclear cells (PBMCs) and fluoropyrimidine-related severe toxicity. We identified substantial issues concerning the use of pretreatment uracil in clinical practice, including large between-center study differences in measured pretreatment uracil levels, most likely as a result of pre-analytical factors. Importantly, we were not able to correlate pretreatment uracil levels with DPD activity nor were uracil levels predictive of severe treatment-related toxicity. We urge that robust clinical validation should first be performed before pretreatment plasma uracil levels are used in clinical practice as part of a dosing strategy for fluoropyrimidines.

DPYD*7 as a Predictor of Severe Fluoropyrimidine-Related Adverse Events

PURPOSE

Around 20%-30% of patients treated with fluoropyrimidines develop severe treatment-related adverse events (AEs). These are mainly caused by deficiency of dihydropyrimidine dehydrogenase, its main metabolizing enzyme. The DPYD*7 variant allele contains a frameshift mutation that leads to absence of dihydropyrimidine dehydrogenase. Clinical studies on this variant in patients treated with fluoropyrimidines are lacking because of its low minor allelic frequency. However, the DPYD*7 minor allelic frequency is 56-times higher in the Dutch compared with the global population. This allowed us to evaluate fluoropyrimidine tolerability in DPYD*7 variant allele carriers.

MATERIALS AND METHODS

Patients treated with standard-of-care fluoropyrimidine who were pretreatment DPYD genotyped for DPYD*2A, *13, 2846A>T, and 1236G>A single-nucleotide polymorphisms were included for analyses. Patients were additionally screened for the DPYD*7 allele (rs72549309, 295-298delTCAT). AEs were graded if they worsened from baseline, according to Common Terminology Criteria for Adverse Events version 5.0. AEs ≥ grade 3 were considered severe.

RESULTS

From 3,748 patients, we found 13 patients carrying heterozygous DPYD*7. Relevant clinical data were available for 11 patients. All patients developed fluoropyrimidine-related AEs, of which five patients developed severe AEs (46%). From these five patients, three patients were started with 65% or 50% of standard dose, but apparently still developed severe toxicity. Because of severe AEs, three patients discontinued treatment prematurely (one patient already started with 50% of standard dose) and one patient who started with 50% of standard dose was further reduced to 35% of standard dose.

CONCLUSION

In this study, the clinical consequences of carrying the DPYD*7 variant allele were confirmed as 46% of the patients developed severe AEs, even in the presence of initial dose reductions. This underlines the need for prospective studies investigating the required fluoropyrimidine dose for DPYD*7 carriers.

Role of Ginseng, Quercetin, and Tea in Enhancing Chemotherapeutic Efficacy of Colorectal Cancer

As the most common gastrointestinal malignancy, colorectal cancer (CRC) remains a leading cause of cancer death worldwide. Although multimodal chemotherapy has effectively improved the prognosis of patients with CRC in recent years, severe chemotherapy-associated side effects and chemoresistance still greatly impair efficacy and limit its clinical application. In response to these challenges, an increasing number of traditional Chinese medicines have been used as synergistic agents for CRC administration. In particular, ginseng, quercetin, and tea, three common dietary supplements, have been shown to possess the potent capacity of enhancing the sensitivity of various chemotherapy drugs and reducing their side effects. Ginseng, also named “the king of herbs”, contains a great variety of anti-cancer compounds, among which ginsenosides are the most abundant and major research objects of various anti-tumor studies. Quercetin is a flavonoid and has been detected in multiple common foods, which possesses a wide range of pharmacological properties, especially with stronger anti-cancer and anti-inflammatory effects. As one of the most consumed beverages, tea has become particularly prevalent in both West and East in recent years. Tea and its major extracts, such as catechins and various constituents, were capable of significantly improving life quality and exerting anti-cancer effects both in vivo and in vitro. In this review, we mainly focused on the adjunctive effects of the three herbs and their constituents on the chemotherapy process of CRC.

Population pharmacogenomics: an update on ethnogeographic differences and opportunities for precision public health

Both safety and efficacy of medical treatment can vary depending on the ethnogeographic background of the patient. One of the reasons underlying this variability is differences in pharmacogenetic polymorphisms in genes involved in drug disposition, as well as in drug targets. Knowledge and appreciation of these differences is thus essential to optimize population-stratified care. Here, we provide an extensive updated analysis of population pharmacogenomics in ten pharmacokinetic genes (CYP2D6, CYP2C19, DPYD, TPMT, NUDT15 and SLC22A1), drug targets (CFTR) and genes involved in drug hypersensitivity (HLA-A, HLA-B) or drug-induced acute hemolytic anemia (G6PD). Combined, polymorphisms in the analyzed genes affect the pharmacology, efficacy or safety of 141 different drugs and therapeutic regimens. The data reveal pronounced differences in the genetic landscape, complexity and variant frequencies between ethnogeographic groups. Reduced function alleles of CYP2D6, SLC22A1 and CFTR were most prevalent in individuals of European descent, whereas DPYD and TPMT deficiencies were most common in Sub-Saharan Africa. Oceanian populations showed the highest frequencies of CYP2C19 loss-of-function alleles while their inferred CYP2D6 activity was among the highest worldwide. Frequencies of HLA-B*15:02 and HLA-B*58:01 were highest across Asia, which has important implications for the risk of severe cutaneous adverse reactions upon treatment with carbamazepine and allopurinol. G6PD deficiencies were most frequent in Africa, the Middle East and Southeast Asia with pronounced differences in variant composition. These variability data provide an important resource to inform cost-effectiveness modeling and guide population-specific genotyping strategies with the goal of optimizing the implementation of precision public health.

Treatment-Related Coronary Disorders of Fluoropyrimidine Administration: A Systematic Review and Meta-Analysis

Background: Coronary disorders are recognized as the most common manifestation of fluoropyrimidine-related cardiotoxicity in clinical practice. However, there are limited and conflicting data on the incidence and profiles of fluoropyrimidine-related coronary disorders. In this meta-analysis, we aimed to systematically assess the incidence of all-grade and grade 3 or higher fluoropyrimidine-related coronary disorders, and further explore the factors that influence its occurrence.

Methods: Studies reporting the fluoropyrimidine-related coronary disorders were retrieved from a systematic search of English literature in the PubMed, Web of Science, Medline, and Cochrane database from 1 Jan 2001, to 1 Jan 2022. The NIH assessment tool was used to evaluate the quality of each study. The data of basic study characteristics, treatment details, and results of coronary toxicities were extracted. According to the results of the heterogeneity test (I² and p-value statistic), a random-effect model or fixed-effect model was selected for the pooled analysis of the incidence of adverse coronary events. Subgroup analysis was conducted to further explore the risks influencing the occurrence of fluoropyrimidine-related coronary disorders. The stability and publication bias of our results were evaluated by sensitivity analysis and Egger test, respectively.

Results: A total of 63 studies were finally included in our pooled analysis, involving 25,577 patients. The pooled cumulative incidence of all-grade and grade 3 or higher coronary disorders was 2.75% (95% CI 1.89%–3.76%) and 1.00% (95% CI 0.62%–1.47%), respectively. The coronary disorders were most reported as myocardial ischemia (1.28%, 95% CI 0.42%–2.49%) and angina/chest pain (1.1%, 95% CI 0.54%–1.81%). Subgroup analysis revealed that studies in the female-only population seemed to have a lower incidence of fluoropyrimidine-related coronary disorders. The occurrence of adverse coronary events varied among different tumor types. Patients with esophageal cancer have the highest coronary toxicity (6.32%), while those with breast cancer have a relatively lower incidence (0.5%). Coronary disorders induced by 5-FU monotherapy are more frequent than that induced by capecitabine (3.31% vs. 1.21%, p < 0.01). Fluoropyrimidine combination therapy, whether combined with other chemotherapy drugs, targeted therapy drugs, or radiotherapy, significantly increased the incidence of coronary complications (p < 0.01).

Conclusion: This meta-analysis has defined the incidence of fluoropyrimidine-related coronary disorders and depicted its epidemiological profiles for the first time, which may provide a reference for clinical practice in cancer management.

Can upfront DPYD extended variant testing reduce toxicity and associated hospital costs of fluoropyrimidine chemotherapy? A propensity score matched analysis of 2022 UK patients

Aim

To independently assess the impact of mandatory testing using an extended DPYD variant panel (ToxNav®) and consequent dose adjustment of Capecitabine/5-FU on recorded quantitative toxicity, symptoms of depression, and hospital costs.

Methods

We used propensity score matching (PSM) to match 466 patients tested with ToxNav® with 1556 patients from a historical cohort, and performed regression analysis to estimate the impact of ToxNav®on toxicity, depression, and hospital costs.

Results

ToxNav® appeared to reduce the likelihood of experiencing moderate (OR: 0.59; 95%CI: 0.45–0.77) and severe anaemia (OR: 0.55; 95%CI: 0.33–0.90), and experience of pain for more than 4 days a week (OR: 0.50; 95%CI: 0.30–0.83), while it increased the likelihood of mild neutropenia (OR: 1.73; 95%CI: 1.27–2.35). It also reduced the cost of chemotherapy by 12% (95%CI: 3–31) or £9765, the cost of non-elective hospitalisation by 23% (95%CI: 8–36) or £2331, and the cost of critical care by 21% (95%CI: 2–36) or £1219 per patient. For the DPYD variant associated with critical risk of toxicity (rs3918290), the improved non-elective hospital costs were > £20,000, whereas variants associated with hand-foot syndrome toxicity had no detectable cost improvement.

Conclusion

Upfront testing of DPYD variants appears to reduce the toxicity burden of Capecitabine and 5-FU in cancer patients and can lead to substantial hospital cost savings, only if the dose management of the drugs in response to variants detected is standardised and regulated.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09576-3.

Identification of pharmacogenetic variants from large scale next generation sequencing data in the Saudi population

It is well documented that drug responses are related to Absorption, Distribution, Metabolism, and Excretion (ADME) characteristics of individual patients. Several studies have identified genetic variability in pharmacogenes, that are either directly responsible for or are associated with ADME, giving rise to individualized treatments. Our objective was to provide a comprehensive overview of pharmacogenetic variation in the Saudi population. We mined next generation sequencing (NGS) data from 11,889 unrelated Saudi nationals, to determine the presence and frequencies of known functional SNP variants in 8 clinically relevant pharmacogenes (CYP2C9, CYP2C19, CYP3A5, CYP4F2, VKORC1, DPYD, TPMT and NUDT15), recommended by the Clinical Pharmacogenetics Implementation Consortium (CPIC), and collectively identified 82 such star alleles. Functionally significant pharmacogenetic variants were prevalent especially in CYP genes (excluding CYP3A5), with 10-44.4% of variants predicted to be inactive or to have decreased activity. In CYP3A5, inactive alleles (87.5%) were the most common. Only 1.8%, 0.7% and 0.7% of NUDT15, TPMT and DPYD variants respectively, were predicted to affect gene activity. In contrast, VKORC1 was found functionally, to be highly polymorphic with 53.7% of Saudi individuals harboring variants predicted to result in decreased activity and 31.3% having variants leading to increased metabolic activity. Furthermore, among the 8 pharmacogenes studied, we detected six rare variants with an aggregated frequency of 1.1%, that among several other ethnicities, were uniquely found in Saudi population. Similarly, within our cohort, the 8 pharmacogenes yielded forty-six novel variants predicted to be deleterious. Based upon our findings, 99.2% of individuals from the Saudi population carry at least one actionable pharmacogenetic variant.

Measurement of 5- fluorouracil, capecitabine and its metabolite concentrations in blood using volumetric absorptive microsampling technology and LC-MS/MS

5-fluorouracil (5-FU) and its oral formulation, capecitabine, are widely used in treating a range of malignancies, either alone or in combination with other antineoplastic drugs. Body surface area-based dosing is used for these agents, despite this approach leading to substantial variability in drug exposure and often resulting in either toxicity or treatment failure. Tailoring therapeutic regimens for individual patients using therapeutic drug monitoring (TDM) has been shown to significantly reduce toxicity and improve cancer outcomes. However, for optimum TDM, sample timing is crucial, along with the need for a venepuncture blood sample to obtain the plasma currently used for 5-FU measurement. In addition to complex blood sample handling requirements, large sample volume and frequent sampling required for pharmacokinetic analysis is another barrier to successfully implementing TDM in a healthcare setting. Microsampling is an alternative collection method to venepuncture, which, combined with the now readily available liquid chromatography mass spectrometry (LC-MS/MS) technology, overcomes the plasma-associated issues. It also has the significant advantage of enabling at home and remote sampling, thus facilitating 5-FU TDM in clinical practice. A LC-MS/MS method for simultaneous measurement of capecitabine, 5'-deoxy-5-fluorocytidine, 5'-deoxy-5-fluorouridine and 5-FU using Mitra® microsampling devices for sample collection was developed. A Shimadzu 8060 LC-MS/MS equipped with electrospray ionisation source interface, operated in positive and negative ion modes, with reversed-phase chromatographic separation was employed for sample analysis. Samples were extracted from Mitra® devices using acetonitrile containing stable isotope-labelled internal standards, sonicated, evaporated under vacuum and resuspended in 0.1 % formic acid before injection into the LC-MS/MS. Chromatographic separation was on a Luna Omega Polar C₁₈ (100 × 2.1 mm, 1.6 µm) column with gradient elution of 0.1 % formic acid in water and acetonitrile. Total run time was 5 min, with the injection volume of 1 µL. The intra and inter-day imprecision ranged from 3.0 to 8.1 and 6.3-13.3 % respectively. Accuracy ranged from 95 -114 % for all analytes. Lower limit of quantification with imprecision of < 19 % and accuracy between 89 and 114 % was 0.05 mg/L for 5-FU and 10 µg/L for other analytes. Assays were linear from 0.05 to 50 mg/L for 5-FU and 10-10,000 µg/L for all other analytes. Analytes were stable on Mitra® devices for up to 9 months at room temperature, 2 years at -30 ℃ and 3 days at 50 ℃. The method was successfully applied for the analysis of samples from patients undergoing cancer treatment with 5-FU and capecitabine. Microsampling using volumetric absorptive microsampling proved to be as reliable as conventional blood collection for 5-FU and capecitabine. This sampling technique may lead to less invasive and better-timed sample collection for TDM, supporting dose optimization strategy.

Deprived social status is associated with decreased use of oral chemotherapy in patients with metastatic colorectal cancer: A retrospective cohort study on administrative databases in a French University Hospital

Factors associated with the choice of oral versus intravenous CT are not clearly established. Our purpose was to evaluate the influence of social status and home distance to hospital on the use of oral CT in patients with metastatic colorectal cancer (mCRC). This retrospective single-center study included mCRC patients between 2011 and 2017. Patient social status was assessed by European Deprivation Index (EDI) and home distance to the hospital was calculated. Univariable and multivariable logistic regression analyses were performed. One hundred and seventy-five mCRC patients were included, with 71 receiving oral CT. Most deprived patients received less oral CT (OR 0.5 [0.26, 0.96], p = .039). No association was found for road distance. Previous use of adjuvant oral CT was associated with oral CT in mCRC (OR 2.65 [1.06, 6.66], p = .038). Our results suggest that deprived social status is a factor associated with decreased use of oral CT in patients with mCRC. Clinical trial registration: no registration.

Genotype-based chemotherapy for patients with gastrointestinal tumors: focus on oxaliplatin, irinotecan, and fluoropyrimidines

This review aimed to summarize the pharmacogenetic studies of the most commonly used drugs in the chemotherapy of gastrointestinal (GI) tumors: oxaliplatin, irinotecan, and fluoropyrimidines. So far, it has not been possible to develop an effective genotype-based approach for oxaliplatin. More and more evidence is emerging in favor of the fact that the choice of a dose of fluorouracil based on pharmacogenetic testing according to DPYD*2A, can be not only effective but also cost-effective. Additional, well-planned trials of the UGT1A1 genotype-based approach to irinotecan therapy are predicted to reduce adverse drug events in people with the UGT1A1*28/*28 genotypes and improve treatment efficacy in the rest of the patients, which might be cost-effective.

DPYD polymorphisms c.496A>G, c.2194G>A and c.85T>C and risk of severe adverse drug reactions in patients treated with fluoropyrimidine-based protocols

AIMS

Cancer patients with reduced dihydropyrimidine dehydrogenase (DPD) activity are at increased risk of severe fluoropyrimidine (FP)-related adverse events (AE). Guidelines recommend FP dosing adjusted to genotype-predicted DPD activity based on four DPYD variants (rs3918290, rs55886062, rs67376798 and rs56038477). We evaluated the relationship between three further DPYD polymorphisms: c.496A>G (rs2297595), *6 c.2194G>A (rs1801160) and *9A c.85T>C (rs1801265) and the risk of severe AEs.

METHODS

Consecutive FP-treated adult patients were genotyped for "standard" and tested DPYD variants, and for UGT1A1*28 if irinotecan was included, and were monitored for the occurrence of grade ≥3 (National Cancer Institute Common Terminology Criteria) vs. grade 0-2 AEs. For each of the tested polymorphisms, variant allele carriers were matched to respective wild type controls (optimal full matching combined with exact matching, in respect to: age, sex, type of cancer, type of FP, DPYD activity score, use of irinotecan/UGT1A1, adjuvant therapy, radiotherapy, biological therapy and genotype on the remaining two tested polymorphisms).

RESULTS

Of the 503 included patients (82.3% colorectal cancer), 283 (56.3%) developed grade ≥3 AEs, mostly diarrhoea and neutropenia. Odds of grade ≥3 AEs were higher in c.496A>G variant carriers (n = 127) than in controls (n = 376) [OR = 5.20 (95% CI 1.88-14.3), Bayesian OR = 5.24 (95% CrI 3.06-9.12)]. Odds tended to be higher in c.2194G>A variant carriers (n = 58) than in controls (n = 432) [OR = 1.88 (0.95-3.73), Bayesian OR = 1.90 (1.03-3.56)]. c.85T>C did not appear associated with grade ≥3 AEs (206 variant carriers vs. 284 controls).

CONCLUSION

DPYD c.496A>G and possibly c.2194G>A variants might need to be considered for inclusion in the DPYD genotyping panel.

The Role of Intestinal Microbiota in Metastatic Colorectal Cancer Patients Treated With Capecitabine

BACKGROUND

Previous pre-clinical research has indicated that the intestinal microbiota can potentiate anti-tumour efficacy of capecitabine and that capecitabine treatment impacts intestinal microbiota composition and diversity. Using a longitudinal design, this study explores the associations between the intestinal microbiota and treatment response in patients with metastatic colorectal cancer (mCRC) during capecitabine treatment.

PATIENTS AND METHODS

Patients with mCRC treated with capecitabine were prospectively enrolled in a multicentre cohort study. Patients collected a faecal sample and completed a questionnaire before, during, and after three cycles of capecitabine. Several clinical characteristics, including tumour response, toxicity and antibiotic use were recorded. Intestinal microbiota were analysed by amplicon sequencing of the 16S rRNA V4 gene-region.

RESULTS

Thirty-three patients were included. After three cycles of capecitabine, six patients (18%) achieved a partial response, 25 (76%) showed stable disease, and one (3%) experienced progressive disease. Of the 90 faecal samples were collected. Microbial diversity (α-diversity), community structure (β-diversity), and bacterial abundance on phylum and genus level were not significantly different between responders and non-responders and were not significantly affected by three cycles of capecitabine.

CONCLUSION

This is the first clinical study with longitudinal intestinal microbiota sampling in mCRC patients that explores the role of the intestinal microbiota during treatment with capecitabine. Intestinal microbiota composition and diversity before, during, and after three cycles of capecitabine were not associated with response in this study population. Capecitabine did not induce significant changes in the microbiota composition and diversity during the treatment period. Individual effects of antibiotics during capecitabine treatment were observed.

Randomized Phase II Trial Evaluating Two Sequential Treatments in First Line of Metastatic Pancreatic Cancer: Results of the PANOPTIMOX-PRODIGE 35 Trial

PURPOSE

Metastatic pancreatic cancer (mPC) still harbors a dismal prognosis. Our previous trial (PRODIGE 4-ACCORD 11) demonstrated the superiority of 6-month chemotherapy with fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX) over gemcitabine for overall survival. The high limiting oxaliplatin-related neurotoxicity supports the evaluation of an oxaliplatin stop-and-go strategy and a sequential strategy in mPC.

METHODS

In this phase II study, patients were randomly assigned to receive either 6 months of FOLFIRINOX (arm A), 4 months of FOLFIRINOX followed by leucovorin plus fluorouracil maintenance treatment for controlled patients (arm B), or a sequential treatment alternating gemcitabine and fluorouracil, leucovorin, and irinotecan every 2 months (arm C). The primary end point was progression-free survival at 6 months.

RESULTS

Between January 2015 and November 2016, 276 patients (mean age: 63 years; range: 40-76 years) were enrolled (A: 91, B: 92, and C: 90). Grade 3 or 4 neurotoxicity occurred in 10.2% of patients in arm A and 19.8% in arm B. The median ratio of received dose/targeted dose of oxaliplatin was 83% in arm A and 92% in arm B. The 6-month progression-free survival was 47.1% in A, 42.9% in B, and 34.1% in C. The median overall survival was 10.1 months in arm A, 11.2 in arm B, and 7.3 in arm C. Median survival without deterioration in quality-of-life scores was higher in the maintenance arm (11.4 months) than in arms A and C (7.2 and 7.5 months, respectively).

CONCLUSION

Maintenance with leucovorin plus fluorouracil appears to be feasible and effective in patients with mPC controlled after 4 months of induction chemotherapy with FOLFIRINOX. Severe neurotoxicity was higher in the maintenance therapy arm, probably because of the higher cumulative dose of oxaliplatin.

Comparative study of low dose of capecitabine versus standard dose in metastatic breast cancer: Efficacy and safety

Background

A lower dose of capecitabine revealed better toxicity profiles and comparable efficacy in treatment of metastatic breast cancer (MBC). We aimed to evaluate the efficacy and toxicity of lower dose of capecitabine in comparison with the standard dose.

Patients and methods

Patients were enrolled in two groups. Group 1 included 21 patients who received the standard dose of capecitabine (1250 mg/m2 twice daily [BID] for 14 days), while the patients in group 2 (19 patients) received lower dose of capecitabine (850 mg/m2 BID for 14 days) every 3 weeks.

Results

In group 1, dose reduction was reported in 12 (57.1%) patients versus 1 patient in group 2 (5.3%; P = 0.0005). Patients in group 1 reported higher toxicity rates without any significant difference between the groups. The median duration of response was 17 weeks in group 1, while it was 19 weeks in group 2. Disease progression was recorded in 10 (47.6%) patients in group 1 versus 8 (42.1%) patients in group 2 (P = 0.81). The mean time to progression was 8.16 ± 0.63 months and the median was 10.1 months in group 1, while the mean was 8.98 ± 0.75 months and the median was 10 months in group 2 (P = 0.66). The overall survival had a mean of 11.94 ± 0.754 and 11.24 ± 0.665 months, while the median was 13.1 and 13 months in groups 1 and 2, respectively (P = 0.9).

Conclusion

A lower dose of capecitabine provides MBC patients with an active therapy that can be continued for prolonged periods to achieve long-term disease control without compromising its antitumor activity.

Chemotherapy: a double-edged sword in cancer treatment

Chemotherapy is a well-known and effective treatment for different cancers; unfortunately, it has not been as efficient in the eradication of all cancer cells as been expected. The mechanism of this failure was not fully clarified, yet. Meanwhile, alterations in the physiologic conditions of the tumor microenvironment (TME) were suggested as one of the underlying possibilities. Chemotherapy drugs can activate multiple signaling pathways and augment the secretion of inflammatory mediators. Inflammation may show two opposite roles in the TME. On the one hand, inflammation, as an innate immune response, tries to suppress tumor growth but on the other hand, it might be not powerful enough to eradicate the cancer cells and even it can provide appropriate conditions for cancer promotion and relapse as well. Therefore, the administration of mild anti-inflammatory drugs during chemotherapy might result in more successful clinical results. Here, we will review and discuss this hypothesis. Most chemotherapy agents are triggers of inflammation in the tumor microenvironment through inducing the production of senescence-associated secretory phenotype (SASP) molecules. Some chemotherapy agents can induce systematic inflammation by provoking TLR4 signaling or triggering IL-1B secretion through the inflammasome pathway. NF-kB and MAPK are key signaling pathways of inflammation and could be activated by several chemotherapy drugs. Furthermore, inflammation can play a key role in cancer development, metastasis and exacerbation.

Management of Metastatic Colorectal Carcinoma in Older Adults: Balancing Risks and Benefits of Novel Therapies

The prevalence of older patients with metastatic colorectal cancer (mCRC) will continue to increase with our aging population. Treatment of mCRC has changed significantly in the last few decades as we have learned how to personalize the treatment of mCRC to the biology of the tumor, utilizing new treatment approaches. With an ever-changing treatment paradigm, managing the population of older adults becomes paramount. This review highlights the pivotal clinical trials that defined the use of systemic therapy, immunotherapy and targeted therapies for mCRC, and how those are applied to the older patient population. In addition, we outline the tools for an in-depth assessment of an older adult in regards to treatment planning and management of therapy-related toxicities. A comprehensive geriatric assessment can assist in the selection of treatment for an older adult with mCRC. While frail older patients can frequently only tolerate single agents or modified regimens, fit older adults remain candidates for a wider range of treatment options. However, since all of these treatments are associated with possible toxicities, each patient's treatment must be personalized to the patient's goals and wishes through a shared decision-making process.

Overview of Evidence-Based Chemotherapy for Oral Cancer: Focus on Drug Resistance Related to the Epithelial-Mesenchymal Transition

The increasing incidence of resistance to chemotherapeutic agents has become a major issue in the treatment of oral cancer (OC). Epithelial-mesenchymal transition (EMT) has attracted a great deal of attention in recent years with regard to its relation to the mechanism of chemotherapy drug resistance. EMT-activating transcription factors (EMT-ATFs), such as Snail, TWIST, and ZEB, can activate several different molecular pathways, e.g., PI3K/AKT, NF-κB, and TGF-β. In contrast, the activated oncological signal pathways provide reciprocal feedback that affects the expression of EMT-ATFs, resulting in a peritumoral extracellular environment conducive to cancer cell survival and evasion of the immune system, leading to resistance to multiple chemotherapeutic agents. We present an overview of evidence-based chemotherapy for OC treatment based on the National Comprehensive Cancer Network (NCCN) Chemotherapy Order Templates. We focus on the molecular pathways involved in drug resistance related to the EMT and highlight the signal pathways and transcription factors that may be important for EMT-regulated drug resistance. Rapid progress in antitumor regimens, together with the application of powerful techniques such as high-throughput screening and microRNA technology, will facilitate the development of therapeutic strategies to augment chemotherapy.

Worse capecitabine treatment outcome in patients with a low skeletal muscle mass is not explained by altered pharmacokinetics

Background

A low skeletal muscle mass (SMM) has been associated with increased toxicity and shorter survival in cancer patients treated with capecitabine, an oral prodrug of 5‐fluorouracil (5‐FU). Capecitabine and its metabolites are highly water‐soluble and, therefore, more likely to distribute to lean tissues. The pharmacokinetics (PK) in patients with a low SMM could be changed, for example, by reaching higher maximum plasma concentrations. In this study, we aimed to examine whether the association between a low SMM and increased toxicity and shorter survival could be explained by altered PK of capecitabine and its metabolites.

Methods

Previously, a population PK model of capecitabine and metabolites in patients with solid tumors was developed. In our analysis, we included patients from this previous analysis for which evaluable abdominal computed tomography (CT)‐scans were available. SMM was measured on CT‐scans, by single slice evaluation at the third lumbar vertebra, using the Slice‐o‐Matic software. The previously developed population PK model was extended with SMM as a covariate, to assess the association between SMM and capecitabine and metabolite PK.

Results

PK and SMM data were available from 151 cancer patients with solid tumors. From the included patients, 55% had a low SMM. No relevant relationships were found between SMM and the PK parameters of capecitabine and, the active and toxic metabolite, 5‐FU. SMM only correlated with the PK of the, most hydrophilic, but inactive and non‐toxic, metabolite α‐fluoro‐β‐alanine (FBAL). Patients with a low SMM had a smaller apparent volume of distribution and lower apparent clearance of FBAL.

Conclusions

No alterations in PK of capecitabine and the active and toxic metabolite 5‐FU were observed in patients with a low SMM. Therefore, the previously identified increased toxicity and shorter survival in patients with a low SMM, could not be explained by changes in pharmacokinetic characteristics of capecitabine and metabolites.