Phase I and pharmacokinetic study of 24-hour infusion 5-fluorouracil and leucovorin in patients with organ dysfunction

Impact of renal impairment on dihydropyrimidine dehydrogenase (DPD) phenotyping

BACKGROUND

The chemotherapeutic agent 5-fluorouracil (5-FU) is catabolized by dihydropyrimidine dehydrogenase (DPD), the deficiency of which may lead to severe toxicity or death. Since 2019, DPD deficiency testing, based on uracilemia, is mandatory in France and recommended in Europe before initiating fluoropyrimidine-based regimens. However, it has been recently shown that renal impairment may impact uracil concentration and thus DPD phenotyping.

PATIENTS AND METHODS

The impact of renal function on uracilemia and DPD phenotype was studied on 3039 samples obtained from three French centers. We also explored the influence of dialysis and measured glomerular filtration rate (mGFR) on both parameters. Finally, using patients as their own controls, we assessed as to what extent modifications in renal function impacted uracilemia and DPD phenotyping.

RESULTS

We observed that uracilemia and DPD-deficient phenotypes increased concomitantly to the severity of renal impairment based on the estimated GFR, independently and more critically than hepatic function. This observation was confirmed with the mGFR. The risk of being classified 'DPD deficient' based on uracilemia was statistically higher in patients with renal impairment or dialyzed if uracilemia was measured before dialysis but not after. Indeed, the rate of DPD deficiency decreased from 86.4% before dialysis to 13.7% after. Moreover, for patients with transient renal impairment, the rate of DPD deficiency dropped dramatically from 83.3% to 16.7% when patients restored their renal function, especially in patients with an uracilemia close to 16 ng/ml.

CONCLUSIONS

DPD deficiency testing using uracilemia could be misleading in patients with renal impairment. When possible, uracilemia should be reassessed in case of transient renal impairment. For patients under dialysis, testing of DPD deficiency should be carried out on samples taken after dialysis. Hence, 5-FU therapeutic drug monitoring would be particularly helpful to guide dose adjustments in patients with elevated uracil and renal impairment.

Decreased Disposition of Anticancer Drugs Predominantly Eliminated via the Liver in Patients with Renal Failure

Background:

Evidence has revealed that renal impairment can affect the systemic exposure of drugs which are predominantly eliminated via the liver. The modulation of drug-metabolizing enzymes and transporters expressed in the liver and/or small intestine by diverse entities, including uremic toxins, in systemic circulation of patients with severe renal failure is considered as the cause of atypical pharmacokinetics, which sometimes induce undesirable adverse events that are especially critical for drugs with narrow therapeutic window such as anticancer drugs. A dosing strategy for anticancer drugs in these patients needs to be established.

Methods:

The effects of renal impairment on the systemic exposure and safety of anticancer drugs were summarized. The proposed mechanisms for the alterations in the pharmacokinetics of these anticancer drugs were also discussed.

Results:

Changes in pharmacokinetics and clinical response were reported in 9 out of 10 cytotoxic anticancer drugs investigated, although available information was limited and sometimes controversial. Systemic exposure of 3 out of 16 tyrosine kinase inhibitors was higher in patients with severe renal failure than that in patients with normal kidney function. An increase in systemic exposure of anticancer drugs in patients with renal impairment is likely to be observed for substrates of OATP1B1, despite the limited evidence.

Conclusion:

The molecular basis for the effect of uremia on non-renal drug elimination still needed to be clarified with further studies to generate generalizable concepts, which may provide insights into establishing better clinical usage of anticancer drugs, i.e. identifying patients at risk and dose adjustment.

Basket Trials for Intractable Cancer

Currently, genomic characterization has become standard of care for tumor types such as non-small cell lung cancer, breast cancer, melanoma, and colorectal cancer. A deep understanding of genomic alterations in different tumor types would help identify potentially actionable genomic changes which occur across a wide variety of tumor types. A basket trial is a new type of clinical trial for which eligibility is based on the presence of a specific genomic alteration, irrespective of histology. Basket trials are phase II screening trials for the off-label use of a targeted drug in patients with the same genomic alterations for which it was approved. Intractable cancer refers to a type or condition of cancer which is unresponsive or resistant to treatment; intractable cancers may be classified into five subtypes as follows: hard-to-treat condition of common advanced cancer after multiple-line therapy, rare cancer in which no standard of care has been recommended, advanced cancer in which standard of care does not work well, cancer accompanied with organ dysfunction, and cancers in older or younger cancer patients. Previous studies have demonstrated that in basket trials, genomic-guided therapy yields clinical benefits in intractable cancer, thereby providing novel insights into the optimal clinical management of such cancers. In this review, we describe a novel way to classify intractable cancer, and summarize the current knowledge on such cancers. We additionally provide information on the role of basket trials in intractable cancer.

A case of an elderly patient with high-grade colorectal cancer in poor general condition who showed near complete response to chemotherapy and achieved long-term survival

•

Systemic therapy can achieve good treatment outcomes in advanced CRC.

•

Suitable chemotherapeutics can markedly improve the prognosis of unresectable CRC.

•

Unresectable CRC can now be treated with systemic chemotherapy instead of BSC.

Introduction

Chemotherapy is difficult to administer in patients with poor performance status (PS), advanced metastatic lesion, and unresectable colon cancer. We report herein our experience of a patient who showed complete response to chemotherapy and marked PS improvement. The patient presented with the following adverse factors poor PS, advanced progression of metastatic lesions, advanced unresectable colorectal cancer with severe stricture, and old age.

Presentation of case

The patient was an 80-year-old male diagnosed with occlusive cancer of the descending colon with multiple metastases in the liver, Stage Ⅳb (National Comprehensive Cancer Network guidelines version 2. 2018). A 5-fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) + panitumumab (Pmab) regimen was successfully administered and led to decreased tumor marker levels; oral intake also became possible. Additional examinations showed that the primary lesion and distant metastatic lesions had almost disappeared; the patient had achieved a near complete response (CR). Currently, 35 cycles of mFOLFOX6＋Pmab have been administered, and his near CR has been maintained for 32 months.

Discussion

Best supportive care (BSC) is the recommended option for elderly patients with advanced unresectable colon cancer. This is the first case in which an elderly patient with poor PS and advanced unresectable colorectal cancer was treated with combination chemotherapy of mFOLFOX6 + Pmab.

Conclusion

Although the use of chemotherapy for elderly with advanced unresectable colorectal cancer or those with poor PS is limited, this case shows that systemic chemotherapy is now an option for such cases previously managed with BSC.

Retrospective Analysis of the Risk Factors for Grade IV Neutropenia in Oesophageal Cancer Patients Treated with a Docetaxel, Cisplatin, and 5-Fluorouracil Regimen

BACKGROUND

Previous Japanese trials of the docetaxel, cisplatin, and 5-fluorouracil regimen for oesophageal cancer have demonstrated that a large proportion of patients also develop grade IV neutropenia. Our aim was to examine the risk factors for neutropenia in patients treated with this regimen.

METHODS

We retrospectively analysed the risk factors for developing grade IV neutropenia in 66 patients with oesophageal cancer using a multivariate analysis.

RESULTS

After administering the docetaxel, cisplatin, and 5-fluorouracil regimen, 49 patients (74.2%) developed grade IV neutropenia. Grade IV neutropenia was significantly associated with platelet count (p < 0.01), alanine transaminase level (p = 0.05), and proton-pump inhibitor administration (p < 0.05). Receiver operating characteristic curve analysis confirmed a platelet count of 290 × 103/μL as the optimal diagnostic cut-off value for grade IV neutropenia. The receiver operating characteristic area for grade IV neutropenia was increased by including patients that were administered a proton-pump inhibitor and alanine transaminase level (updated model; sensitivity and specificity, 75.5 and 88.2%, respectively).

CONCLUSIONS

Our findings suggest that a platelet count is the most significant predictor of grade IV neutropenia.

Chemotherapy in patients with hepatobiliary cancers and abnormal hepatic function

Sorafenib and cisplatin plus gemcitabine currently represent first-line treatment standards in advanced hepatocellular carcinoma and biliary cancer, respectively. Conventional cytotoxic agents (monotherapy or combination therapy) have demonstrated activity in the second-line setting or in those in which first-line agents are contraindicated. A strategy for safe yet effective administration of such systemic therapies in patients with advanced hepatobiliary cancer and abnormal liver function needs to be strongly considered. Here, we highlight the safety and tolerability of systemic therapies routinely used for the treatment of advanced hepatobiliary cancer in patients with hepatic dysfunction. Based on data from available clinical studies, we review dosing strategies recommended for chemotherapy and targeted therapy in those with liver dysfunction. Dose modifications for many agents in this population remain empiric due to limited clinical evidence. Future dedicated phase I studies are needed to provide further dosing considerations for combination therapy in those with abnormal liver function in which data is lacking.

Patients with Metastatic Colorectal Cancer and Hyperbilirubinemia Treated with FOLFIRI plus Bevacizumab as First-Line Treatment

Metastatic colorectal cancer (mCRC) combined with hyperbilirubinemia is typically considered a contraindication to irinotecan-based therapy, a proven first-line treatment of mCRC. Herein, we present 6 consecutive patients with mCRC combined with hyperbilirubinemia who underwent UGT1A1 genotyping before receiving FOLFIRI plus bevacizumab. Dose escalation of irinotecan was performed according to the results of UGT1A1 genotyping in all patients. Improvement in the serum total bilirubin level to a normal range was noted in all 6 patients. Disease control was 100%. The median progression-free survival was 7.5 months and the median overall survival was 8.5 months. FOLFIRI plus bevacizumab as a first-line chemotherapy may achieve effective disease control and be safe in patients with mCRC and hyperbilirubinemia based on UGT1A1 genotyping. More prospective clinical studies are necessary to evaluate the clinical benefits and safety of this treatment approach.

Chemotherapy in the Setting of Severe Liver Dysfunction in Patients with Metastatic Colorectal Cancer

The liver is the dominant site of metastases for patients with metastatic colorectal cancer (mCRC). Depending on the timing of diagnosis and the biology of the disease, it is not uncommon for these patients to present with visceral crisis in the form of severe liver dysfunction. Treatment of these individuals is, however, difficult and challenging. The decision to consider chemotherapy in these dire circumstances entails consideration of numerous factors. If we were to focus on just the metabolism of the different drugs and biologic agents available to treat mCRC, both 5-fluorouracil and oxaliplatin alone or in combination with a monoclonal antibody are reasonable choices. Specifically, FOLFOX is a feasible and safe option in patients with mCRC with severe liver dysfunction. Choice of the biologic agent to add to the doublet chemotherapy could be individualized based on the RAS status and the clinical scenario. Based on the divergent experience of treating 2 cases and other prior reports, a summary of recommendations with a model in the form of a “therapeutic triad” is presented. The paper highlights the therapeutic challenges in patients with mCRC and severe liver dysfunction. The choice of chemotherapeutic agents and reports of other cases/series is also presented.

Circadian variation in plasma 5-fluorouracil concentrations during a 24 hour constant-rate infusion

Background

Varying the rate of continuous intravenous infusions of 5-fluorouracil (5FU) chemotherapy over a 24-hour period has been reported to improve patient outcomes. It has been hypothesized that circadian variation in drug disposition is a contributing factor. We analyzed 5-FU concentrations during a 24-hour continuous 5-FU infusion.

Methods

Sixty-four subjects with advanced malignancies including pancreatic, hepatocellular, colorectal as well as other epithelial malignancies and either abnormal hepatic or renal function were treated on a phase I and pharmacokinetic study of weekly 24-hour intravenous infusions of 5-FU and leucovorin. No other concomitant anticancer therapy was administered. Blood samples were collected every three hours from 61 subjects for measurement of plasma 5-FU during the first two weekly infusions.

Results

After adjusting for differences in dose, elapsed time from start of infusion and infusion number (2 versus 1), mean 5-FU concentration was highest at 6 am and lowest at 3 pm, with an overall change in the mean from 3 pm to 6 am of +20 percent (95% CI = 12–28%). However, this variation in mean concentration associated with time of day was comparable in magnitude to the between-patient differences, within-patient differences between infusions, and the residual variation within infusion (coefficient of variation = 21%).

Conclusions

Our data show systematic variation by time of day in plasma concentrations of 5-FU administered at a constant rate over 24 hours, but it is small compared to the total variation in plasma concentration contributed by other sources. Circadian variation in men was more pronounced than in women.

Hepatotoxicity Secondary to Chemotherapy

The difficult problem faced by multiple generation of practicing physicians is determining the cause of abnormal liver function tests in cancer patients on chemotherapy. Hepatotoxicity from chemotherapy occurs frequently from an unpredictable or idiosyncratic reaction. Despite remarkable advances in our understanding of the mechanisms of action, pharmacodynamics, and interrelationships between the liver and chemotherapy, the underlying etiology of hepatic toxicity for various agents remains unexplained. Here, we present a concise review of the broad differential diagnosis for abnormal liver function tests (LFTs) in oncology patients.

Differential effects of arsenic trioxide on chemosensitization in human hepatic tumor and stellate cell lines

BACKGROUND

Crosstalk between malignant hepatocytes and the surrounding peritumoral stroma is a key modulator of hepatocarcinogenesis and therapeutic resistance. To examine the chemotherapy resistance of these two cellular compartments in vitro, we evaluated a well-established hepatic tumor cell line, HepG2, and an adult hepatic stellate cell line, LX2. The aim was to compare the chemosensitization potential of arsenic trioxide (ATO) in combination with sorafenib or fluorouracil (5-FU), in both hepatic tumor cells and stromal cells.

METHODS

Cytotoxicity of ATO, 5-FU, and sorafenib, alone and in combination against HepG2 cells and LX2 cells was measured by an automated high throughput cell-based proliferation assay. Changes in survival and apoptotic signaling pathways were analyzed by flow cytometry and western blot. Gene expression of the 5-FU metabolic enzyme, thymidylate synthase, was analyzed by real time PCR.

RESULTS

Both HepG2 and LX2 cell lines were susceptible to single agent sorafenib and ATO at 24 hr (ATO IC(50): 5.3 μM in LX2; 32.7 μM in HepG2; Sorafenib IC(50): 11.8 μM in LX2; 9.9 μM in HepG2). In contrast, 5-FU cytotoxicity required higher concentrations and prolonged (48-72 hr) drug exposure. Concurrent ATO and 5-FU treatment of HepG2 cells was synergistic, leading to increased cytotoxicity due in part to modulation of thymidylate synthase levels by ATO. Concurrent ATO and sorafenib treatment showed a trend towards increased HepG2 cytotoxicity, possibly due to a significant decrease in MAPK activation in comparison to treatment with ATO alone.

CONCLUSIONS

ATO differentially sensitizes hepatic tumor cells and adult hepatic stellate cells to 5-FU and sorafenib. Given the importance of both of these cell types in hepatocarcinogenesis, these data have implications for the rational development of anti-cancer therapy combinations for the treatment of hepatocellular carcinoma (HCC).

Should cirrhosis change our attitude towards treating non-hepatic cancer?

Cirrhosis is a major cause of morbidity and mortality and is the end stage of any chronic liver disease. Cancer, a leading cause of death worldwide, is a growing global health issue. There are limited data in the literature on the incidence, prevalence and management of non-hepatic cancers (NHC) in cirrhotic patients. The aim of this brief review was to underline the main concerns, pitfalls and warnings regarding practice for these patients. Survival of patients with compensated cirrhosis is significantly longer than that of decompensated cirrhosis and patients with NHC and in Child-Pugh class C should not be candidates for cytotoxic chemotherapy. It is important before starting cytotoxic chemotherapy to assess the aetiology and stage of liver disease and to screen these patients for portal hypertension and fluid retention. During cytotoxic chemotherapy, the effectiveness of cancer treatment, as well the appearance of early signs of hepatic decompensation, must be thoroughly monitored. Future phase 3 trial designs in oncology should include a share of patients with compensated cirrhosis to obtain specific information in this setting. Identification of tests able to measure the global degree of hepatic impairment caused by cirrhosis could help in the management of this particular clinical situation.

5FU continuous infusion in heavily pretreated advanced breast cancer patients

BACKGROUND

Despite advances in the first- and secondline treatment of advanced breast cancer, optimal therapy thereafter remains controversial. Treatment of heavily pretreated patients is not standardized, often of low efficacy, and limited by comorbidity. In these patients, an effective treatment with low toxicity is needed.

PATIENTS AND METHODS

We retrospectively analyzed all metastatic breast cancer patients treated with 5-fluorouracil as continuous infusion (CI-5FU) with daily doses of 150-300 mg/m(2).

RESULTS

43 patients were treated with CI-5FU until disease progression. The median number of metastatic sites was 3. Most patients were heavily pretreated with a median of 3 palliative chemotherapies (range 1-11). 42 patients were evaluable for objective response; among them 5 (12%) showed a partial response (PR) and 6 (15%) showed stable disease (SD) lasting at least 6 months, leading to a clinical benefit (CB) rate (complete response + PR + SD ≥ 6 months) of 27%. The median time to progression of patients with CB was 10 months (range 3-22). Overall survival of all patients from the start of CI-5FU was 8 months (range 1-75) and from the time of first metastases 42 months (range 9-281). Toxicity was low even in patients with hepatic insufficiency.

CONCLUSION

CI-5FU showed a positive efficacy/toxicity ratio. Taking into account the high number of previous treatments, it results in a remarkable CB rate of 27%.

Safe use of FOLFOX in two patients with metastatic colorectal carcinoma and severe hepatic dysfunction

BACKGROUND

Chemotherapeutic options for patients with metastasised colorectal cancer and impaired liver function are limited. Although oxaliplatin and 5-FU are well tolerated as single therapeutic agents, data supporting their use as combination chemotherapy in the setting of severe hepatic dysfunction are insufficient.

PATIENTS AND METHODS

Here, we report on 2 patients with colorectal cancer and severe liver dysfunction secondary to hepatic metastases. On admission both patients displayed a bilirubin of > 22 mg/dL and an alkaline phosphatase (AP) of > 350 U/L as signs of extensive hepatic tumor spread. We initiated a 5-FU/oxaliplatin-based combination chemotherapy in both patients.

RESULTS

Liver function and clinical performance improved dramatically within the first cycles of therapy in both patients. On radiologic evaluation, we observed 1 partial response and one long-term (10 months) disease stabilization. The toxicity was acceptable in both patients.

CONCLUSION

We concluded that oxaliplatin-based combination chemotherapies (eg FOLFOX4) may achieve good tumor response without significant side effects in patients with metastatic colorectal cancer and hepatic dysfunction.

Metastatic colorectal cancer with severe liver dysfunction successfully treated using FOLFOX therapy

INTRODUCTION

The liver is the most frequent site of metastases from colorectal cancer (CRC), and extensive liver metastases often cause severe secondary liver dysfunction. However, whether chemotherapy for metastatic CRC with severe liver dysfunction offers any clinical benefit is unclear since patients in this setting are typically excluded from clinical trials.

DISCUSSION

We report herein a case of metastatic sigmoid colon cancer with severe liver dysfunction that was successfully treated using infusional 5-fluorouracil, leucovorin, and oxaliplatin (FOLFOX). FOLFOX was effective and well tolerated in the present case, and subsequent addition of bevacizumab to FOLFOX after disease progression was similarly feasible.

Combination therapy with oxaliplatin and 5-fluorouracil in a patient with severe hepatic dysfunction associated with metastatic adenocarcinoma of the large bowel

Oxaliplatin has been shown to be valuable in the treatment of patients with colorectal cancer. Many of these patients will develop liver metastases during the course of their disease, with, in some cases, severe hepatic dysfunction. Although single agent oxaliplatin can be administered safely in patients with severely compromised liver function (as it is not metabolized by the liver), little is known of its safety in these patients when administered in the preferred combination with 5-fluorouracil (which is metabolized by the liver) and leucovorin (FOLFOX protocol). We report on a very sick patient with major liver dysfunction, a bilirubin of 11.2 mg/dl (190 micromol/dl) and an open abdominal wound, for whom palliative hospice care alone was originally proposed, who responded dramatically to the combination. His bilirubin fell to 0.6 mg/dl (10.2 micromol/dl) and his liver function tests returned to near normal levels. The combination was well tolerated and clinical improvement continued for more than 11 months before disease progression was observed.

Part II: Liver function in oncology: towards safer chemotherapy use

The liver is fundamentally important in drug metabolism. In oncology, the astute clinician must not only understand the meaning and limitations of commonly ordered liver biochemical tests, but also be aware of which anticancer agents might induce liver dysfunction, and of the strategies for appropriate dosing of patients with pre-existing liver dysfunction. In part I of our Review, we highlighted both the importance and inadequacies of identifying serum biochemical liver abnormalities in oncology; we also discussed a lack of routine formal investigation of liver function. We summarised chemotherapy-related hepatotoxicity and other causes of liver toxic effects in patients with cancer. Here in part II, we discuss trials that have specifically assessed chemotherapy dosing strategies in the setting of overt biochemical liver dysfunction and we note their recommendations. Furthermore, we review other assessments of liver metabolic and excretory function, particularly in the setting of chemotherapy drug handling. We discuss the potential use of these metabolic probes in practice.

Commentary: Oncologic drugs in patients with organ dysfunction: a summary

There are few prospective data regarding the pharmacokinetics and clinical toxicity of commonly used chemotherapeutics in cancer patients with organ dysfunction. Although increasing numbers of studies are investigating newer chemotherapeutics in patients with liver or kidney dysfunction, most guidelines for dosing, especially for established agents, remain empiric. This review describes the available data (both prospective and case study) evaluating the impact of renal and hepatic dysfunction on toxicity and dosing of commonly used chemotherapeutics and provides a practical summary for their use in this setting.

Systemic anticancer therapy in gynecological cancer patients with renal dysfunction

Chronic kidney disease is a common occurrence in patients with gynecological cancer. Systemic anticancer treatment in such patients is a challenge for clinicians because of altered drug pharmacokinetics. For those drugs that are excreted mainly by the kidneys, decreased renal function may lead to increased systemic exposure and increased toxicity. Dose adjustment based on pharmacokinetic changes is required in this situation to avoid life-threatening toxicity. In this review, we summarize the nephrotoxicity and pharmacokinetic data of agents commonly used in systemic anticancer treatment of gynecological cancers and dose adjustment guidelines in the presence of impaired renal function. We review 17 medications that need dose adjustment (cisplatin, carboplatin, doxorubicin, epirubicin, cyclophosphamide, ifosfamide, topotecan, irinotecan, etoposide, capecitabine, bleomycin, methotrexate, actinomycin D, granulocyte-macrophage colony-stimulating factor, metoclopramide, cimetidine, and diphenhydramine) as well as 27 drugs that do not (paclitaxel, docetaxel, pegylated liposomal doxorubicin, gemcitabine, oxaliplatin, fluorouracil, vincristine, letrozole, anastrozole, tamoxifen, leuprorelin, megestrol, gefitinib, erlotinib, trastuzumab, leucovorin, granulocyte colony-stimulating factor, erythropoietin, ondansetron, granisetron, palonosetron, tropisetron, dolasetron, aprepitant, dexamethasone, lorazepam, and diazepam). We also review the formulae commonly used to estimate creatinine clearance, including Cockcroft-Gault, Chatelut, Jelliffe, Wright, and the Modification of Diet in Renal Disease study formulae.

Profiling dihydropyrimidine dehydrogenase deficiency in patients with cancer undergoing 5-fluorouracil/capecitabine therapy

Fluoropyrimidine drugs such as 5-fluorouracil (5-FU) and capecitabine are a mainstay in the treatment of numerous solid tumors, including colorectal cancers, alone or as part of combination therapies. Cytotoxic drugs such as 5-FU and oral capecitabine display narrow therapeutic indexes combined with high interpatient pharmacokinetic variability. As a result, severe toxicities often limit or delay the administration of successive, optimal chemotherapeutic courses, leading to unfavorable clinical outcome in patients with cancer. Catabolism and deactivation of fluoropyrimidine drugs depend on a single and exclusive enzymatic step driven by dihydropyrimidine dehydrogenase (DPD). Dihydropyrimidine dehydrogenase is prone to marked circadian rhythms, drug-drug interactions, and genetic polymorphisms; influence of its erratic activity on 5-FU pharmacokinetics and toxicity profile has been extensively investigated, and it is now well known that DPD deficiency leads to severe toxicities with 5-FU or possibly capecitabine exposure. With the ever-increasing number of patients with cancer likely to be treated with fluoropyrimidines, predicting and preventing the occurrence of such toxicities is now a major issue in clinical oncology. Early determination of DPD status in patients with cancer would allow identification of those at risk and help in subsequent dose adjustment or selection of other treatment modalities. Numerous methods, either genotypic or phenotypic, have been proposed to achieve this goal. This review covers a wide range of techniques available to establish DPD status in patients with cancer.

How may anticancer chemotherapy with fluorouracil be individualised?

Fluorouracil is used clinically against various solid tumours. Both fluorouracil toxicity and pharmacokinetics vary highly within and between individuals. The reasons why doses are not individualised routinely are difficulties in defining, predicting and achieving an optimal fluorouracil exposure or dose because of a narrow therapeutic index, nonlinear pharmacokinetics, variabilities in administration rates and metabolism, and in targets like thymidylate synthase. To individualise fluorouracil administration before the first dose, assessment of the individual dihydropyrimidine dehydrogenase (DPD) activity may be useful, because this genetically highly polymorphic enzyme controls approximately 80% of fluorouracil elimination. A complete or partial loss of DPD activity in 0.1 and 3-5% of Caucasians, respectively, leads to increased fluorouracil exposure and toxicity. Several methods to assess DPD activity in patients have been proposed (genotyping, various phenotyping methods), but each of them has limitations, as has the fluorouracil test dose approach. To adapt exposure towards fluorouracil a priori, a combination of genotyping and phenotyping may yield better prediction of toxicity than one method alone. A prerequisite for dose adaptation is the definition of fluorouracil exposure ranges with sufficient therapeutic activity, but without serious toxicity. While an increased risk of leukopenia, diarrhoea, stomatitis, and hand-foot syndrome during continuous 5-day infusions was related to fluorouracil exposures above an area under the plasma concentration-time curve (AUC) threshold of 25-30 mg.h/L, tumour response was higher when an AUC of approximately 30 mg.h/L was achieved, illustrating the extremely narrow therapeutic window of fluorouracil. Pharmacokinetic target values are less clear for other regimens, including chronomodulated regimens, which yielded a superior clinically efficacy and tolerability in several trials. However, the monitoring of fluorouracil plasma concentrations seems principally useful for individual a posteriori dose adjustment. Whether an adaptation of the fluorouracil starting dose to the results of two DPD activity tests before fluorouracil administration a priori, and the adaptation of doses to fluorouracil exposure a posteriori is a reasonable approach to better prevent toxicity and increase efficacy, remains to be evaluated in randomised clinical studies comparing these strategies to routine clinical safety monitoring.

Nutritional, functional, and emotional characteristics related to fatigue in patients during and after biochemotherapy

PURPOSE/OBJECTIVES

To test Winningham's psychobiologic entropy hypothesis in patients receiving biochemotherapy for melanoma.

DESIGN

Descriptive, correlational, cross-sectional study.

SETTING

Midwest cancer center.

SAMPLE

25 male and female patients who were receiving biochemotherapy or who had completed treatment 6-12 months prior.

METHODS

Data were collected using a series of questionnaires and diet recall.

MAIN RESEARCH VARIABLES

Fatigue, anxiety, depression, distressing symptoms, nutritional intake, and weight.

FINDINGS

Moderate fatigue was significantly related to physiologic and psychological symptoms but not to nutrient intake. The sample was overweight, and a significant number of participants were obese. High caloric intakes were evident. Depression was a significant problem.

CONCLUSIONS

Fatigue was not as severe as expected, but problems with responses to the fatigue scale may explain this. Nutritional status and nutrient intake were not correlated to fatigue in this sample. Activity levels were related to fatigue, and treatment reduced activity. On average, activity returned to pretreatment levels 6-12 months after treatment. Winningham's hypothesis held and will be useful for understanding fatigue in this population.

IMPLICATIONS FOR NURSING

Depression needs to be assessed and treated as a side effect of biotherapy. Assessing the impact of nutrition when patients are overweight or obese is difficult. A scale specifically designed to test Winningham's hypothesis is needed.

5-fluorouracil leucovorin and oxaliplatin (FOLFOX) in the treatment of metastatic colon cancer with severe liver dysfunction

Colon cancer patients with severe hepatic dysfunction secondary to liver metastases have limited treatment options. 5-Fluorouracil (5-FU) infusional therapy has been attempted, but data suggesting significant clinical benefit are lacking. Although both 5-FU and oxaliplatin have been well tolerated as single agents in patients with severe hepatic dysfunction, the combination of these drugs in this setting has not been investigated. We report on three patients with severe liver dysfunction secondary to metastatic colon cancer treated with a combination of 5-FU, oxaliplatin, and leucovorin (FOLFOX). All three patients tolerated chemotherapy well without any significant toxicity. Liver function tests improved within 2 weeks from the start of treatment. Clinical outcomes consisted of two partial responses and one disease stabilization. Two patients progressed after 4 and 7 months from FOLFOX initiation while treatment is ongoing in the third patient. FOLFOX chemotherapy is feasible and can be associated with positive outcomes in patients with metastatic colon cancer and severe hepatic dysfunction. This regimen should be investigated further in similar clinical settings.