Cardiac Toxicity of 5-Fluorouracil: A Study on 1083 Patients

Cardiotoxicity induced by chemotherapy and antibody therapy

Modern cancer therapy employs a combination of chemotherapy, antibody-based therapy, radiotherapy, and surgery to prolong life and provide cure. However, many of the chemotherapy agents and antibodies, either singly or in combination, can affect the cardiovascular system. Common cardiovascular manifestations of these therapies include heart failure, ischemia, hypotension, hypertension, edema, QT prolongation, bradyarrhythmia, and thromboembolism. The patient's age, underlying cardiovascular status, and genetic background, as well as the route of drug administration and dosage, can all contribute to the development of cardiotoxicity. Strategies to monitor for and to manage these effects are discussed in this review.

Acute coronary syndrome induced by oral capecitabine

A 41-year-old woman who was undergoing oral chemotherapy with capecitabine for metastatic breast cancer presented with recurrent episodes of chest pain associated with electrocardiographic signs of diffuse ST segment elevation. After spontaneous pain relief, the electrocardiogram showed ischemic evolution in the anterior precordial leads. Coronary and ventricular angiography, performed 24 h later, showed normal coronary arteries and normal left ventricular function. After therapy with capecitabine was discontinued, the patient did not experience further episodes of chest pain. After a nine-month follow-up, she remains alive, with a good performance status and without clinical evidence of persistent ischemia.

Vascular Toxicity of Antineoplastic Agents

Among the various deleterious effects of cancer chemotherapy, vascular toxicity is the least well recognized. This lack of recognition may be because the vasculotoxic phenomena are not unique to antineoplastic agents, can occur in patients without exposure to these agents, and the fact cancer itself may produce a hypercoagulable state. As a result, many vascular events either go unnoticed, are ignored, and/or are attributed to the underlying malignancy. Many antineoplastic therapies are associated with various vascular phenomena that range from simple phelibitis to lethal microangiopathy. Recognition of these events is important to minimize the morbidity and even prevent unnecessary deaths. Herein we review the vascular syndromes that have been reported in association with antineoplastic agents.

Risk factors and prevention of cardiotoxicity induced by 5-fluorouracil or capecitabine

AIM

5-fluorouracil (5-FU) and its prodrug capecitabine are cardiotoxic. This retrospective study aimed to identify risk factors and to give practical measures to make such chemotherapy feasible if cardiotoxicity occur.

METHOD

Review of cardiotoxicity among 668 patients treated with 5-FU or capecitabine for gastrointestinal cancers.

RESULTS

Cardiotoxicity occurred in 29 cases (4.3%). The number of cases according to cardiotoxicity CTC grades 2-4 for patients with and without pre-existing cardiovascular disease were none, 10, and 2 cases, and 3, 14, and no cases, respectively (P=0.16). In three patients intercurrent decrease of renal clearances to <30, 48 and 71 ml min(-1) led to markedly increased cardiotoxicity. Chemotherapy dose reduction to 70 or 50%, either alone or in addition to antiangina medication prevented cardiotoxicity during subsequent chemotherapy in nine (60%) and three (20%) cases out of 15 assessable patients (P=0.001), respectively. To abolish symptoms of cardiotoxicity, sublingual nitroglycerine was efficient for 15 patients and inefficient for two (P=0.001).

CONCLUSION

Cardiac and renal co-morbidity are risk factors for 5-FU induced cardiotoxicity. In this situation, rechallenge with modified 5-FU-based chemotherapy regimen supported by symptomatic medical treatment is feasible.

Cardiac function after chemoradiation for esophageal cancer: comparison of heart dose-volume histogram parameters to multiple gated acquisition scan changes

In this paper we determine if preoperative chemoradiation for locally advanced esophageal cancer leads to changes in cardiac ejection fraction. This is a retrospective review of 20 patients treated at our institution for esophageal cancer between 2000 and 2002. Multiple gated acquisition cardiac scans were obtained before and after platinum-based chemoradiation (50.4 Gy). Dose-volume histograms for heart, left ventricle and left anterior descending artery were analyzed. Outcomes assessed included pre- and postchemoradiation ejection fraction ratio and percentage change in ejection fraction postchemoradiation. A statistically significant difference was found between median prechemoradiation ejection fraction (59%) and postchemoradiation ejection fraction (54%) (P = 0.01), but the magnitude of the difference was not clinically significant. Median percentage volume of heart receiving more than 20, 30 and 40 Gy were 61.5%, 58.5% and 53.5%, respectively. Our data showed a clinically insignificant decline in ejection fraction following chemoradiation for esophageal cancer. We did not observe statistically or clinically significant associations between radiation dose to heart, left ventricle or left anterior descending artery and postchemoradiation ejection fraction.

Cardiac troponins as biomarkers of drug- and toxin-induced cardiac toxicity and cardioprotection

Cardiac troponin T and I (cTnT, cTnI) are sensitive biochemical markers of myocardial cell necrosis and have been adopted as the gold standard tests for acute myocardial infarction. Subtle elevations in cTn above the detection limits of the currently available commercial assays confers poor prognosis. These markers are superior to classical enzyme markers of necrosis due to their cardiospecificity. The diagnosis of drug-induced cardiac toxicity using the classical enzymes is problematic due to the high elevations of these markers in skeletal muscle necrosis. cTnT and cTnI are now being adopted as sensitive biomarkers of drug-induced cardiac toxicity.

Cardiotoxicity of cancer chemotherapy: implications for children

Many children and adolescents with cancer receive chemotherapeutic agents that are cardiotoxic. Thus, while survival rates in this population have improved for some cancers, many survivors may experience acute or chronic cardiovascular complications that can impair their quality of life years after treatment. In addition, cardiac complications of treatment lead to reductions in dose and duration of chemotherapy regimens, potentially compromising clinical efficacy. Anthracyclines are well known for their cardiotoxicity, and alkylating agents, such as cyclophosphamide, ifosfamide, cisplatin, busulfan, and mitomycin, have also been associated with cardiotoxicity. Other agents with cardiac effects include vinca alkaloids, fluorouracil, cytarabine, amsacrine, and asparaginase and the newer agents, paclitaxel, trastuzumab, etoposide, and teniposide. The heart is relatively vulnerable to oxidative injuries from oxygen radicals generated by chemotherapy. The cardiac effects of these drugs include asymptomatic electrocardiographic abnormalities, blood pressure changes, arrhythmias, myocarditis, pericarditis, cardiac tamponade, acute myocardial infarction, cardiac failure, shock, and long-term cardiomyopathy. These effects may occur during or immediately after treatment or may not be apparent until months or years after treatment. Mild myocardiocyte injury from chemotherapy may be of more concern in children than in adults because of the need for subsequent cardiac growth to match somatic growth and because survival is longer in children. Primary prevention is therefore important. Patients should be educated about the cardiotoxic risks of treatment and the need for long-term cardiac monitoring before chemotherapy is begun. Cardiotoxicity may be prevented by screening for risk factors, monitoring for signs and symptoms during chemotherapy, and continuing follow-up that may include electrocardiographic and echocardiographic studies, angiography, and measurements of biochemical markers of myocardial injury. Secondary prevention should aim to minimize progression of left ventricular dysfunction to overt heart failure. Approaches include altering the dose, schedule, or approach to drug delivery; using analogs or new formulations with fewer or milder cardiotoxic effects; using cardioprotectants and agents that reduce oxidative stress during chemotherapy; correcting for metabolic derangements caused by chemotherapy that can potentiate the cardiotoxic effects of the drug; and cardiac monitoring during and after cancer therapy. Avoiding additional cardiotoxic regimens is also important in managing these patients. Treating the adverse cardiac effects of chemotherapy will usually be dependent on symptoms or will depend on the anticipated cardiovascular effects of each regimen. Treatments include diuresis, afterload reduction, beta-adrenoceptor antagonists, and improving myocardial contractility.

Treatment of stage IV colorectal carcinoma in elderly patients

Colorectal adenocarcinoma ranks second as a cause of death due to cancer in the Western world. In Europe, 40% of patients with colorectal cancer are over 70 years old and the incidence increased through the 1980's. Without any treatment the median survival after the detection of liver metastases is approximately 9 months, depending on the extent of disease at the time of diagnosis but not on the patients age. In the elderly there are only few data apt to define the standard regimen in the advanced disease, but results seem similar to those observed in younger patients. As a result of exclusion criteria and screening, elderly patients entering clinical trials are usually a select group, with good performance status, access to transportation, and limiting numbers of coexisting conditions. This paper examines the factors pertinent to the small number of clinical trials designed for metastatic colorectal cancer in this group of persons.

The frequency and pattern of cardiotoxicity observed with capecitabine used in conjunction with oxaliplatin in patients treated for advanced colorectal cancer (CRC)

We examined the cardiotoxicity in 153 patients treated with capecitabine and oxaliplatin in two prospective trials for advanced colorectal cancer. Ten patients (6.5%) developed cardiac events. One patient (0.7%) had sudden death, one patient developed cardiac failure with raised troponin I while another developed ventricular tachycardia (VT). The remaining seven patients (4.6%) experienced angina and three of the seven patients had raised troponin I, one of which developed ventricular fibrillation. Eight events occurred within cycle 1 (median cycle 1 day 10). Four patients with angina and one patient with VT recovered on stopping capecitabine, four patients required additional medical management and the remaining patient died suddenly at home. Patients with ischaemic heart disease appeared to be at increased risk. Physicians and patients need to be aware of these complications, so that prompt discontinuation of treatment and appropriate interventions may be instituted.

[Reversible cardiogenic shock under 5-fluorouracil treatment]

5-fluorouracil, an antimetabolite agent, has been widely used since 1957 for treatment of varied types of cancer such as gastro-intestinal, pancreas, breast, lung, head and neck malignancies. Cardiotoxicity of 5-fluorouracil is rare and was first described in 1975. It can induce severe complications and involve vital prognosis in the short-term. These complications are less known by cardiologists than medical oncologists. The following clinical case represents a potentially serious and rare case of completely reversible cardiogenic shock in a patient with a colo-rectal cancer. A better knowledge of these complications could reduce cases of death by an earlier diagnosis, and a better evaluation of patients with high cardiotoxicity risk.

Ultrasound Tissue Characterization by Integrated Backscatter for Analyzing Fluorouracil Induced Myocardial Damage

BACKGROUND

5-Fluorouracil (5-FU) cardiotoxicity is a well-known clinical phenomenon whose pathophysiology remains controversial. Cyclic variation of integrated backscatter (CVIBS) assesses acoustic properties of myocardium that may reflect both contractility and structural changes. The aim of this study was to evaluate CVIBS alterations in cancer patients under high-dose leucovorin and infusional 5-FU (HDLV5FU) chemotherapy.

METHOD

We prospectively evaluated 37 cancer patients under HDLV5FU treatment. Transthoracic echocardiography and CVIBS were performed at the 0th, 48th hours, and on day 15 of the first cycle. The parasternal long-axis view was preferred to obtain the image of integrated backscatter and mainly two regions of interest--interventricular septum (IVS) and posterior wall (PW)--were used.

RESULTS

Clinical cardiotoxicity was observed in two patients. No significant differences were detected in pre- and posttreatment conventional echocardiography evaluations. However, both the IVS (9.3 +/- 1.0 to 8.1 +/- 1.2 dB, P < 0.001) and PW (9.1 +/- 0.7 to 7.8 +/- 0.9 dB, P < 0.001) CVIBS values significantly decreased in all patients. All values were returned to pretreatment levels (9.2 +/- 0.9 dB in the CVIBS-IVS and 8.9 +/- 0.6 dB in CVIBS-PW, respectively) on day 15 after the treatments.

CONCLUSION

This study suggests that HDLV5FU may cause acute transient alterations in CVIBS values in the absence of clinical symptoms and signs of cardiotoxicity. The clinical value of CVIBS should be further studied in patients receiving 5-FU-based therapy.

Influence of high-dose leucovorin and 5-fluorouracil chemotherapy regimen on P wave duration and dispersion

BACKGROUND

Although 5-fluorouracil (5-FU)-related cardiotoxicity is well known, atrial arrhythmia, as a potentially serious complication has not been studied in detail. The aim of this study was to determine the P max and Pd in the electrocardiograms (ECG) of patients receiving 5-FU treatment.

METHODS

Twenty-five patients (mean age: 62 years) receiving a 5-FU bolus plus continuous infusion with calcium leucovorin over 48 h and with normal pre-treatment cardiac physical examinations, ECG and echocardiography were enrolled. P maximum (P max), P minimum (P min) and P dispersion (Pd) (maximum minus minimum P wave duration) were measured from the 12-lead ECG at the 0th and 48th hour of the first chemotherapy cycle. Echocardiography was also obtained in all patients at the same times.

RESULTS

Clinical cardiotoxicity was observed in two patients. P max and Pd were both significantly longer after 5-FU treatment at the 48th hour (P < 0.001). P min did not change (P > 0.05).

CONCLUSION

Treatment with 5-FU based regimens may increase Pd and prolong the P max in cancer patients. These alterations may be predictive of patients at risk of atrial arrhythmias during 5-FU treatment.

Cardiovascular complications of cancer therapy: diagnosis, pathogenesis, and management

The cardiotoxicity of anticancer agents can lead to significant complications that can affect patients being treated for various malignancies. The severity of such toxicity depends on many factors such as the molecular site of action, the immediate and cumulative dose, the method of administration, the presence of any underlying cardiac condition, and the demographics of the patient. Moreover, toxicity can be affected by current or previous treatment with other antineoplastic agents. Cardiotoxic effects can occur immediately during administration of the drug, or they may not manifest themselves until months or years after the patient has been treated. In this article we review commonly used chemotherapy agents, including several recently approved medications, for their propensity to cause cardiotoxicity. Further research will be required to more accurately predict which patients are at risk for developing cardiotoxicity. In addition, management plans, as well as strategies to reduce cardiotoxicity, need to be developed.

Capecitabine-induced coronary vasospasm--a case report

The authors report the case of a 70-year-old man with metastatic colon cancer and no known history of coronary disease or major risk factors who developed coronary vasospasm after the initiation of capecitabine (Xeloda). Although coronary vasospasm has been associated with another older fluoropyrimidine compound, 5-fluorouracil, this is the first reported occurrence with this relatively newer cancer drug.

[Angina related to 5-Fluorouracil]

Treatment with 5-fluorouracil is common in oncological patients. Side effects on bone marrow, skin, and mucous membranes have been reported. Cardiotoxicity, which is less predictable, can be life-threatening. Manifestations include angina, arrhythmias, infarction, heart failure and cardiogenic shock. The toxic mechanisms that might be involved have been much discussed but have not yet been clearly established. Current evidence supports the possibility of a metabolic effect in common with the cascade secondary to ischemia due to coronary disease. Based on a case report, we discuss the usual clinical presentation, treatment and prognosis. Finally we make recommendations for managing patients being treated with 5-fluorouracil.

Chemotherapy-induced cardiotoxicity: current practice and prospects of prophylaxis

Cardiotoxicity is a potential side effect of few chemotherapeutic agents. The anthracycline class of cytotoxic antibiotics are the most famous, but other chemotherapeutic agents can also cause serious cardiotoxicity and are not so well recognised. Examples include cyclophosphamide, ifosfamide, mitomycin and fluorouracil. Prediction and hence prophylaxis has always been a difficult task. Ideal monitoring techniques, upon which efficient prophylaxis depends, are yet to be determined. Current prophylaxis relies upon early detection of systolic and/or diastolic dysfunction. While somewhat useful, in some cases by the time defects are detected progression of chemotherapy-induced cardiomyopathy is beyond prevention. Prophylaxis would be much more efficient if a biochemical marker of myocardiocyte damage could be reliably used to stop further chemotherapy at the correct time before irreversible progressive 'macroscopic' damage becomes evident upon imaging. Work is currently progressing to identify the role of markers such as troponins and natriuretic peptides in this regard.

Capecitabine can induce acute coronary syndrome similar to 5-fluorouracil

Capecitabine is a member of a new class of oral fluoropyrimidines. It is a 5-fluorouracil (5-FU) prodrug, activated by a series of enzymes. Activation has been demonstrated to occur preferentially in tumor tissue, which may explain the favorable balance of efficacy and toxicity of this drug. Cardiotoxicity, a rare but potentially serious adverse effect of 5-FU, has not been reported for capecitabine to date. Here we report a patient who experienced a severe and prolonged acute coronary syndrome during treatment with capecitabine. He had previously developed similar symptoms during treatment with infusional 5-FU. Capecitabine should thus be considered an agent with cardiotoxic potential. This adverse effect should be specifically monitored in all patients treated with capecitabine. Patients with symptoms suggestive of cardiotoxicity during previous treatment with a fluoropyrimidine should not be treated with capecitabine.

Circulatory shock

Patients with malignancy may present with acute circulatory compromise requiring ICU monitoring and care. The clinician must be familiar with a multiplicity of acute and chronic medical conditions common to the general population and also with conditions directly related to cancer or therapy thereof.

Chemotherapy in elderly patients with colorectal cancer

BACKGROUND

Colorectal cancer is usually diagnosed in patients around 70 years of age. With a continuous increase in life expectancy we may expect a higher number of elderly patients in the future. Because patients above 70 or 75 years are often excluded there is uncertainty as to what extent systemic adjuvant and palliative treatment should be offered to elderly patients.

METHODS

We reviewed the available literature on adjuvant and metastatic colorectal cancer in order to identify reports on elderly patients treated within chemotherapy trials.

RESULTS

Only about 20% of patients entering clinical trials belong to the age group of over 70 years and represent the minority of the very fit patients. Compared to their younger counterparts 5-FU-based treatment appears to be equally effective and more toxic according to some reports. Data regarding raltitrexed, oral fluoropyrimidines, topoisomerase I inhibitors or DACH-platin derivates are limited but suggest no age-specific differences in activity or toxicity.

CONCLUSIONS

Elderly patients should not be excluded from clinical trials and studies in unfit elderly patients are warranted. Elderly patients need more attention regarding their functional, social and mental status. Fit elderly patients should be offered adjuvant or palliative chemotherapy.

Cardiotoxicity of 5-flourouracil: two case reports

Cardiotoxicity is a rare but serious side effect of 5-flourouracil (5-FU). The cardiotoxicity incidence of 5-FU is increasing with its frequent use in chemotherapy protocols. To explain the mechanism of this cardiotoxicity, many theories have been suggested by different authors. Most commonly, coronary artery vasospasm and flouroacetate,a toxic metabolite of 5-FU, are considered responsible for the toxicity. Ischemic symptoms and signs related to 5-FU are observed during the late phase of the administration of the drug. The close and careful monitorization of all the patients, especially the ones with pre-existent coronary artery disease, during 5-FU infusion is mandatory. Because there is not a single and effective modality of treatment or prophylaxis for 5-FU cardiotoxicity, the patients should be selected carefully for 5-FU administration and 5-FU infusion should be stopped as soon as a symptom is encountered.

Antithrombotic treatment in protection against thrombogenic effects of 5-fluorouracil on vascular endothelium: a scanning microscopy evaluation

Cardiotoxicity is a serious side effect of treatment of malignant diseases with 5-fluorouracil (5-FU). The underlying pathophysiologic mechanism remains unclear but clinical data suggest that the endothelium of coronary arteries may be involved. Experimental studies indicate that the endothelium is especially susceptible to 5-FU and support the hypothesis that a thrombogenic effect of 5-FU, secondary to its direct toxic effect on the endothelium, is one of the pathophysiologic mechanisms behind 5-FU-induced cardiotoxicity. In the present study we evaluate the role of antithrombotic treatment with dalteparin as protection against the thrombogenic effect of 5-FU on the vascular endothelium in a rabbit model. The effects on the vascular endothelium of 5-FU, dalteparin, and the combination of these two substances were evaluated with scanning electron microscopy 1, 3, 7, 14, and 30 days after treatment and compared with a control group. Very severe damage to the endothelium was seen in 5-FU-treated animals, often leading to intima disruption and denudation of underlying structures, with accompanying platelet accumulation and fibrin formation. The most extensive damage was observed on Day 3 after treatment. The cytotoxic effect of 5-FU was partly reversible. The combination of 5-FU and dalteparin gave lower scores on Day 3 because of less evidence of thrombotic events. However, the reversibility of the endothelial damage was poorer in this group, as well as in the group that received dalteparin alone. The findings support the hypothesis that antithrombotic treatment with dalteparin can protect against the thrombogenic effect of 5-FU, secondary to its direct toxic effect on the vascular endothelium. However, the study indicates that dalteparin per se has a toxic effect on the endothelium that is different from that of 5-FU.

Acute reversible cardiomyopathy and thromboembolism after cisplatin and 5-fluorouracil chemotherapy--a case report

Acute development of cardiomyopathy and occlusive thromboembolic events following cisplatin and 5-fluorouracil (5-FU) is rare but frequently lethal. The authors report the successful management of such an event in a 52-year-old man with squamous cell carcinoma of the soft palate. The possible pathophysiological mechanisms are discussed.

[Emergency coronary angioplasty following treatment with 5-fluorouracil]

INTRODUCTION

The incidence of cardiac toxicity due to 5-fluorouracil (5-FU) ranges from 1.2 to 18%. Most complications occur at the time of the first cure. Their mechanisms have not yet been clearly defined.

EXEGESIS

The authors report a case of unstable angina induced by 5-FU. A coronary angioplasty was performed on a previously ignored coronary lesion.

CONCLUSION

Recent studies support the hypothesis that 5-FU has endothelial toxicity resulting in thrombogenic effect and release of vasoactive substances. Unstable angina pectoris would be related to plaque rupture caused by 5-FU. Patients with previous history of coronary disease are at significantly increased risk for 5-FU-induced cardiotoxicity. They probably would benefit from continuous electrocardiographic monitoring. Rechallenge with 5-FU after cardiotoxicity problems should include only those patients for whom there is no alternative treatment.

Cardiotoxicity of chemotherapeutic agents: incidence, treatment and prevention

Cytostatic antibiotics of the anthracycline class are the best known of the chemotherapeutic agents that cause cardiotoxicity. Alkylating agents such as cyclophosphamide, ifosfamide, cisplatin, carmustine, busulfan, chlormethine and mitomycin have also been associated with cardiotoxicity. Other agents that may induce a cardiac event include paclitaxel, etoposide, teniposide, the vinca alkaloids, fluorouracil, cytarabine, amsacrine, cladribine, asparaginase, tretinoin and pentostatin. Cardiotoxicity is rare with some agents, but may occur in >20% of patients treated with doxorubicin, daunorubicin or fluorouracil. Cardiac events may include mild blood pressure changes, thrombosis, electrocardiographic changes, arrhythmias, myocarditis, pericarditis, myocardial infarction, cardiomyopathy, cardiac failure (left ventricular failure) and congestive heart failure. These may occur during or shortly after treatment, within days or weeks after treatment, or may not be apparent until months, and sometimes years, after completion of chemotherapy. A number of risk factors may predispose a patient to cardiotoxicity. These are: cumulative dose (anthracyclines, mitomycin); total dose administered during a day or a course (cyclophosphamide, ifosfamide, carmustine, fluorouracil, cytarabine); rate of administration (anthracyclines, fluorouracil); schedule of administration (anthracyclines); mediastinal radiation; age; female gender; concurrent administration of cardiotoxic agents; prior anthracycline chemotherapy; history of or pre-existing cardiovascular disorders; and electrolyte imbalances such as hypokalaemia and hypomagnesaemia. The potential for cardiotoxicity should be recognised before therapy is initiated. Patients should be screened for risk factors, and an attempt to modify them should be made. Monitoring for cardiac events and their treatment will usually depend on the signs and symptoms anticipated and exhibited. Patients may be asymptomatic, with the only manifestation being electrocardiographic changes. Continuous cardiac monitoring, baseline and regular electrocardiographic and echocardiographic studies, radionuclide angiography and measurement of serum electrolytes and cardiac enzymes may be considered in patients with risk factors or those with a history of cardiotoxicity. Treatment of most cardiac events induced by chemotherapy is symptomatic. Agents that can be used prophylactically are few, although dexrazoxane, a cardioprotective agent specific for anthracycline chemotherapy, has been approved by the US Food and Drug Administration. Cardiotoxicity can be prevented by screening and modifying risk factors, aggressively monitoring for signs and symptoms as chemotherapy is administered, and continuing follow-up after completion of a course or the entire treatment. Prompt measures such as discontinuation or modification of chemotherapy or use of appropriate drug therapy should be initiated on the basis of changes in monitoring parameters before the patient exhibits signs and symptoms of cardiotoxicity.

Severe cardiotoxicity during 5-fluorouracil chemotherapy: a case and literature report

The chemotherapeutic agent 5-fluorouracil (5-FU) is a widely accepted part of many cancer treatment protocols. Its cardiotoxic potential is known, but considered uncommon and usually not life threatening, although some cases of severe cardiotoxicity related to 5-FU have been reported. The pathogenesis of cardiotoxicity caused by 5-FU is not clear. We report a case of sudden onset of severe cardiac failure, without ischemic symptoms or signs, during 5-FU treatment with serious consequences, in a previously healthy 23-year-old patient with squamous cell carcinoma of the tongue. Endomyocardial biopsy showed proliferation of the sarcoplasmic reticulum with marked vacuolization, similar to that found with doxorubicin cardiotoxicity. Because 5-FU cardiotoxicity is unpredictable and can have potentially fatal consequences, it requires, in our opinion, further clarification. With this well-documented case, including an endomyocardial biopsy, we hope to encourage additional efforts to investigate the pathophysiologic mechanisms of 5-FU cardiotoxicity.

5-fluorouracil: a pharmacological paradigm in the use of cytotoxics

1. Painstaking progress in drug development is well illustrated by 5-fluorouracil (5FU), originally designed 40 years ago as a fluorinated analogue of the naturally occurring base uracil. Innovative pharmacokinetic and pharmacodynamic strategies have seen significant clinical improvements for cancer patients over the past decade. 2. 5-Fluorouracil acts by three main mechanisms. Principally, the intermediate metabolite fluorodeoxyuridine monophosphate inhibits a key enzyme in pyrimidine biosynthesis, namely thymidylate synthase (TS). Additionally, 5FU is metabolized to ribo- and deoxy-ribonucleotides, which act as false bases for incorporation into RNA and DNA. 3. Biomodulation of 5FU has been attempted with methotrexate (MTX), folinic acid, interferons, cisplatin and radiotherapy. Methotrexate augments the actions of 5FU by inhibiting dihydrofolate reductase and decreasing the folate pool required for pyrimidine biosynthesis, inhibiting TS via MTX-polyglutamate and directly inhibiting purine biosynthesis. Interferons increase steady state concentrations of 5FU. 5-Fluorouracil enhances the cytotoxicity of cisplatin and radiotherapy by inhibiting DNA repair. Folinic acid enhances TS inhibition by increasing the intracellular pool of folates that stabilize the 5FU-TS complex. 4. 5-Fluorouracil has a short plasma half-life. Thymidylate synthase inhibition is limited to the S-phase of the cell cycle and only a small fraction of most cancer cells are in S-phase at any one time. Increased response rates seen with infusional protocols may reflect the effective recruitment of additional mechanisms of cytotoxicity, not dependent on cell cycle, including effects on RNA synthesis. 5. Patients with localized metastatic disease may benefit from locoregional treatments. These include hepatic intra-arterial therapy with related compounds, such as floxuridine, which reach high concentrations at sites of tumour, while systemic toxicities are minimized by efficient hepatic clearance. 6. Recent developments include orally bioavailable formulations, such as ftorafur, capecitabine and the combination of 5FU with the dihydropyrimidine phosphate dehydrogenase inhibitor ethynyluracil. Recognition of diurnal variation in the activity of such key enzymes as DPD has led to the administration of 5FU at regulated, variable infusion rates (chronomodulation). These promising pharmacological approaches may further improve clinical outcomes in common cancers.

Toxic cardiogenic shock in a patient receiving weekly 24-h infusion of high-dose 5-fluorouracil and leucovorin

A 54-year-old man was treated with weekly 24-h infusion of high-dose 5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon cancer. At first, he tolerated the treatment well and no significant toxicity was identified. After a total of eight courses of treatment, a stable disease was observed, but mild shortness of breath was found on occasion. The patient had no previous history of cardiac disease and the heart performance assessed by left ventricular ejection fraction before treatment was normal. Unfortunately, acute pulmonary edema with lethal cardiogenic shock occurred during the ninth course of treatment, in spite of intensive medical treatment. The chest X-ray showed extreme cardiomegaly. Repeated assessment of his heart function by echocardiogram and ventricular ejection fraction revealed a very poor cardiac performance. Toxic cardiogenic shock during weekly 24-h infusion of high-dose 5-fluorouracil and leucovorin is extremely rare. To the best of our knowledge, no case has been reported in the English literature. We report a case and the relevant literature about the incidence, clinical picture and possible pathophysiology on 5-fluorouracil-related cardioxicity is reviewed.

Weekly 24-hour infusion of high-dose 5-fluorouracil and leucovorin in patients with advanced colorectal cancer: Taiwan experience

Between January 1994 and November 1995, 41 patients with metastatic colorectal carcinoma were enrolled in this study. All these patients had recurrent disease after a prior 5-fluorouracil based adjuvant chemotherapy or failed to achieve response by prior chemotherapy that included 5-fluorouracil. 5-Fluorouracil, 2600 mg/m2, was administered concurrently with 100 mg/m2 leucovorin over 24 hours of continuous intravenous infusion. The treatment was repeated every week until progressive disease was documented. Forty-one patients received a total of 810 courses of treatment. The overall response rate was 17.1% (95% confidence interval 5.6-28.6%). In two patients who achieved complete response, the liver was the metastatic site. The median survival was 18.4 months for responders and 12.6 months for non-responders. Gastrointestinal toxicities including diarrhea, stomatitis, nausea and vomiting were the major side-effects. Sixteen incidences (39.0%) of grade 2-3 gastrointestinal toxicities were observed. One patient (2.4%) developed a grade 3 cardiac toxicity, and another one (2.4%) had a grade 2 neurotoxicity. Hematological toxicities were minimal with no evidence of severe (grade 2 or more) leukopenia or thrombocytopenia. We conclude that in patients with pretreated metastatic colorectal cancer, weekly 24-hour infusion of high-dose 5-fluorouracil and leucovorin is associated with higher efficacy and tolerable toxicity. This regimen is a good option as a second-line treatment for those whose diseases are recurrent from or refractory to prior 5-fluorouracil, and deserves a longer period of follow-up.

Noninvasive evaluation of cardiotoxicity of 5-fluorouracil and low doses of folinic acid: a one-year follow-up study

PURPOSE

To conduct a serial evaluation of the cardiac effects of antineoplastic therapy with 5-fluorouracil (5-FU) and low-dose folinic acid.

PATIENTS AND METHODS

Sixteen patients with colon-rectal carcinoma, without cardiac disease, treated with 400 mg/ m2/die of 5-FU and 20 mg/m2/die of folinic acid for five days, once a month, for six months. Parameters evaluated: blood pressure, ECG, two-dimensional and digitized M-mode echocardiograms before and after the first and fifth drug administrations of the first cycle, after the fifth drug administration of the sixth cycle and six months after the treatment.

RESULTS

Blood pressure, heart rate, left ventricular (LV) diameter and LV mass index did not change; all of the patients showed a decrease in the peak shortening rate of the LV diameter index of systolic function, and of the peak lengthening rate of the LV diameter and peak thinning rate of LV posterior wall, indexes of diastolic function, with abnormal values in 11 patients at the end of treatment LV wall motion remained normal in all; two patients developed transient T wave inversion without chest pain and with normal cardiac enzymes and myocardial scintigraphy during dypiridamole stress test. Six months after the treatment all indexes of LV systolic and diastolic function had returned within the normal limits and were similar to pre-treatment values.

CONCLUSIONS

5-FU and low-dose folinic acid treatment induced a decrease of LV systolic function and an impairment of diastolic function, that developed without symptoms and were transient and reversible.

Cisplatin and continuous infusion of fluorouracil followed by radiation and weekly carboplatin in the treatment of locally advanced head and neck cancer: a Hellenic Cooperative Oncology Group study

Induction chemotherapy followed by radiation has been extensively studied in an effort to improve local control and possibly overall survival of patients with locally advanced head and neck cancer. From June 1989 until May 1991, 39 patients with locally advanced squamous cell carcinoma of the head and neck (SCCHN) were treated with 3 cycles of induction chemotherapy, consisting of cisplatin (100 mg/m2 d 1) and fluorouracil (1000 mg/m2 d 2-6) followed by radiation potentiated by weekly administration of carboplatin (60 mg/m2). Surgery was performed in selected patients with residual disease after the combined modality approach. Four cycles of adjuvant chemotherapy with carboplatin (325 mg/m2) and bleomycin (15 u) were administered in those patients who demonstrated a partial response after locoregional treatment. There were 36 men and 3 women with a median age of 56 (range 39-74) years and Karnofsky performance status of 70 (range 60-100). The primary site of the tumor was nasopharynx (8), oropharynx (8), hypopharynx (3), oral cavity (4), larynx (13), paranasal sinus (2), and salivary glands (1). Thirty-two (82%) patients presented with stage IV disease. After the completion of induction chemotherapy, 14 (36%, 95% CI 21-53%) patients achieved a complete response (CR). This CR rate was increased to 56% (95% CI, 42-74%) after locoregional treatment. Main toxicities included nausea/vomiting (56%), leukopenia (40%), anemia (30%), thrombocytopenia (10%), stomatitis (28%), diarrhea (17%), and alopecia (12%). Median relapse-free survival was 18 (1-50) months, median time to progression was 13 (0.3-58.5) months, and median survival 19 (0.3-59) months. Induction chemotherapy with cisplatin and fluorouracil followed by radiation potentiated with carboplatin is feasible. However, this combined modality approach, as applied in the present study, does not appear to yield superior results than those reported with chemotherapy followed by radiation alone.

Intermittent continuous infusion of 5-fluorouracil and low dose oral leucovorin in patients with gastrointestinal cancer: relationship between plasma concentrations and clinical parameters

Modulation of 5-fluorouracil (5-FU) by leucovorin and continuous infusion of 5-FU can both result in enhanced therapeutic efficacy. The main objective of this study was to determine the maximum tolerated dose (MTD) of oral leucovorin in combination with continuous infusion of 5-FU for 14 days every 4 weeks at a dose of 300 mg/m2/day in 30 patients with gastrointestinal cancer. The MTD of oral leucovorin was established at 10 mg/day. Dose-limiting toxicities were mucositis, diarrhoea and hand-foot syndrome. Plasma leucovorin concentrations were below the detection limit of the assay (< 0.5 microM). Plasma 5-FU concentrations varied considerably from 0.06 to 11.3 microM. A relation between toxicity, response and plasma concentration of 5-FU could not be established. Our data may indicate that even very low plasma concentrations of leucovorin are able to modulate 5-FU. In 17 patients with colorectal cancer the response rate was 24% (95% CI: 7-50%), which is comparable to other treatment schedules with leucovorin or to continuous infusion of 5-FU alone.

Chemoradiation in advanced nonsmall cell lung cancer

PURPOSE

Resectability, local control, and survival were evaluated in advanced stage nonsmall cell lung cancer treated with simultaneous chemoradiation therapy delivered in an accelerated, interrupted twice-a-day schedule.

METHODS AND MATERIALS

Forty-seven consecutive patients with Stage IIIA or IIIB nonsmall cell lung cancer, consenting to participation in the study, received cisplatin, 30 mg/m2 for 3 days, etoposid, 80 mg/m2 for 3 days, and 5-fluorouracil, 900 mg/m2 for 4 days. Radiation therapy consisted of 2 Gy given twice a day for 5 days. Two weeks rest was planned between cycles. Patients were evaluated for resectability after the second cycle. Any patient with unresectable tumor received a third cycle of treatment.

RESULTS

Forty-seven patients were evaluable for acute toxicity: eighteen (38%) required an extended rest period for esophagitis or low blood count; 3 (6%) had sepsis, of whom 1 (2%) expired. Three patients (6%) had multiple blood transfusions for low hemoglobin. Median follow-up is 23.6 months, with a range of 10-49 months. Nine patients (19%) failed locally; 15 (32%) had local and distant failure; 7 (15%) failed only at distant sites. Twelve patients (25.5%) are alive with no evidence of disease; 4 patients were lost to follow-up with disease. The 2-year actuarial survival is 49%, and the 4-year is 28.2%.

CONCLUSION

Simultaneous chemoradiation is well tolerated with acceptable toxicity. The overall 2- and 4-year actuarial survival is somewhat better than that reported in the literature. Resectability in Stage IIIB patients was not increased with this regimen nor was any surgical specimen free of cancer. The 47% distant failure rate is not different from those reported by others.

Changes of blood viscosity in patients treated with 5-fluorouracil--a link to cardiotoxicity?

Cardiotoxicity is a serious but relatively unknown side-effect of treatment with 5-fluorouracil (5-FU). The underlying mechanism of 5-FU cardiotoxicity has not been defined. The aim of the present study was to determine whether hemorheological factors might in part explain 5-FU cardiotoxicity. Changes of blood and plasma viscosity, fibrinogen and hematocrit were studied in 11 patients treated by 5-FU. The study showed a decrease in blood and plasma viscosity during treatment with 5-FU, probably caused by a decrease of plasma fibrinogen. Reversible cardiotoxic effects were demonstrated in four patients.

The spectrum of 5-fluorouracil cardiotoxicity

OBJECTIVE

To report three cases of cardiotoxicity related to the administration of 5-fluorouracil (5-FU) in patients with cancer.

CLINICAL FEATURES

Three patients with gastrointestinal malignancies were being treated with combined radiotherapy and chemotherapy regimens. Two patients developed myocardial ischaemia and the other a ventricular arrhythmia in association with 5-FU administration.

INTERVENTION AND OUTCOME

All patients survived the cardiac event. No patient was rechallenged with 5-FU. Radiotherapy was continued, achieving a good tumour response.

CONCLUSION

Cardiotoxicity is rarely reported with 5-FU. The cardiac events can be life threatening. It is difficult to predict which patients will be affected. Clinicians need to be aware of this potential toxicity and monitor patients appropriately.

Fluorouracil cardiotoxicity

OBJECTIVE

To review the clinical manifestations, postulated mechanisms, and therapeutic implications of fluorouracil-induced cardiac toxicity.

DATA SOURCE

A MEDLINE search was used to identify pertinent literature.

STUDY SELECTION

Studies and case reports on fluorouracil cardiotoxicity were identified through a MEDLINE search. A manual review of bibliographies of identified articles was performed to ensure that all pertinent articles were included.

DATA EXTRACTION

Data pertaining to all aspects of fluorouracil cardiac toxicity, including pathogenesis, predisposing factors, clinical manifestations, and therapeutic implications, were evaluated.

DATA SYNTHESIS

Estimates from large series suggest a 1.6-2.3 percent incidence of clinically demonstrated cardiotoxicity. Predisposing factors include the presence of coronary artery disease and concurrent radiotherapy. Postulated mechanisms include direct myocardial ischemia, coronary spasm, or cardiotoxic impurities in fluorouracil formulation. Clinical manifestations include chest pain, nausea, diaphoresis with typical ischemic electrocardiographic (ECG) changes, relieved to normal after stopping the drug therapy. Nitrates and calcium-channel blockers do not protect against cardiotoxicity.

CONCLUSIONS

Fluorouracil cardiotoxicity may be much more common and clinically significant than previously thought. A high index of suspicion for cardiotoxicity must be maintained when the drug is administered, especially in the presence of heart disease and concomitant radiation therapy. In the presence of chest pain, it is mandatory to stop the infusion and, if possible, to replace fluorouracil with another chemotherapeutic agent.

Myocardial ischemia after 5-fluorouracil chemotherapy

A 40-year-old male patient with carcinoma of the tonsil was put on a 5-fluorouracil and cisplatinum regimen. On day 2 during 5-fluorouracil infusion, he had features of myocardial ischemia manifesting as angina and ST-elevation in ECG. These vasospastic ischemic changes subsided after nitroglycerine plus nifedipine therapy. Such vasospastic toxicity of 5-fluorouracil is rare and few such cases have been reported.

Cardiotoxicity of 5-fluorouracil in combination with folinic acid in patients with gastrointestinal cancer

BACKGROUND

Cardiotoxicity related to the widely used cytotoxic compound 5-fluorouracil (5-FU) is rare compared with the frequency observed with the use of anthracyclines. More effective protocols incorporating active biomodulatory compounds like folinic acid (FA) or combination chemotherapy change type and severity of toxicity as well. The objective of the current study was to assess cardiotoxicity of the combination 5-FU and folinic acid.

METHODS

The authors' multicenter experience with 390 patients treated for advanced gastrointestinal cancer with intermediate-dose folinic acid and 5-FU was reviewed.

RESULTS

The overall risk of cardiotoxicity was 3%, which is not significantly higher than that reported with 5-FU alone. Eight of 53 patients with a history of cardiac disease reported cardiac symptoms (15.1%), compared with 5 of 337 patients (1.5%) with a no history of cardiac disease. Median time to symptoms was 3 days (range, 2-6). Nine patients had symptoms resembling myocardial ischemia, one patient died due to assumed myocardial infarction related closely to fluorouracil treatment, four patients had supraventricular arrhythmia, and one patient had congestive heart failure. A history of cardiac disease was the only risk factor associated with cardiotoxicity. Relapses were frequent on reinstitution of therapy despite cardiac symptoms in the preceding cycle. Therapeutically or prophylactically administered nitrates had no significant effect.

CONCLUSION

Physicians should be aware of the cardiotoxic properties of active fluorouracil treatment. The combination of 5-FU and leucovorin does not differ from single-agent therapy in frequency or type of cardiotoxicity. Close monitoring of patients is mandatory, especially for those patients at high risk for cardiac side effects. Treatment should be discontinued if coronary symptoms develop, because neither effective treatment nor prophylaxis exists for such symptoms.

Cisplatin, 5-fluorouracil, and etoposide for advanced non-small cell lung cancer

BACKGROUND

Cisplatin and etoposide combination chemotherapy is the most commonly used regimen for advanced non-small cell lung cancer (NSCLC). 5-Fluorouracil (5-FU) is an agent with little intrinsic activity against NSCLC: However, there is increasing evidence that 5-FU is synergistic with cisplatin and vice versa. In an effort to improve on the traditional chemotherapeutic approach to NSCLC, a treatment regimen consisting of cisplatin, 5-FU, and etoposide (PFE) was developed.

METHODS

Thirty-five patients with advanced NSCLC were treated with the PFE regimen (cisplatin 25/mg/m2/d and 5-FU 1000 mg/m2/d by continuous infusion and etoposide 60 mg/m2/d, each for 4 days). The cycles were repeated every 28 days.

RESULTS

The patients received a mean of 2.8 cycles of PFE. Ten patients had a partial response to chemotherapy for an overall response rate of 28.6%. The median survival was 7.0 months. Toxicities included myocardial infarction (2 of 35), congestive heart failure (2 of 35), fatal pulmonary embolus (1 of 35), and a cerebrovascular accident (1 of 35). The incidence of Grade 4 neutropenia (5.7%) and thrombocytopenia (8.5%) was acceptable.

CONCLUSIONS

The response rate, duration of response, and survival in this group of 35 patients treated with PFE was similar to that reported for cisplatin and etoposide. The increased cardiovascular toxicity may be the result of the infused 5-FU.

Simultaneous chemoradiation in advanced non-small cell lung cancer

We designed our study to evaluate the safety and efficacy of simultaneous chemoradiation therapy in an accelerated, twice-a-day schedule to improve local control and survival in advanced lung cancer patients. Forty-one patients were entered into the study. Twenty-three had stage IIIB and 18 had stage IIIA disease. They received cisplatin 30 mg/m2, VP-16 80 mg/m2, and 5-Fluorouracil (5-FU) 900 mg/m2 in iv infusion. Radiation therapy consisted of 2G twice a day for 5 days, followed by a 2-week rest. This cycle was repeated 3 times. Patients were evaluated for surgical resection after the second cycle. Acute toxicity was acceptable: 3 patients expired (1 congestive heart failure, 1 sepsis, 1 pulmonary embolism). The 1-year actuarial survival was 60.3%; the 2-year actuarial survival was 55.3%. Our results show that this regimen is well tolerated and that the 2-year actuarial survival appears to be comparable to that reported in the literature.