Effect of allopurinol on the toxicity of high-dose 5-fluorouracil administered by intermittent bolus injection

Systematic review of miscellaneous agents for the management of oral mucositis in cancer patients

PURPOSE

The aim of this systematic review was to analyze the available literature and define clinical practice guidelines for the use of the following agents for the prevention and treatment of oral mucositis (OM): allopurinol, midline mucosa-sparing radiation blocks, payayor, pentoxifylline, timing of radiation therapy (RT) (morning versus late afternoon), pilocarpine, bethanechol, chewing gum, propantheline, and tetrachlorodecaoxide.

METHODS

A systematic review was conducted by the Mucositis Study Group of the Multinational Association of Supportive Care in Cancer/International Society for Oral Oncology (MASCC/ISOO). The body of evidence for each intervention, in each cancer treatment setting, was assigned an evidence level. Based on the evidence level, one of the following three guideline determinations was possible: recommendation, suggestion, no guideline possible.

RESULTS

A total of 32 papers across 10 interventions were examined. New suggestions were developed against the use of systemic pilocarpine administered orally for prevention of OM during RT in head and neck cancer patients and in patients receiving high-dose chemotherapy, with or without total body irradiation, prior to hematopoietic stem cell transplantation. A suggestion was also made against the use of systemic pentoxifylline administered orally for the prevention of OM in patients undergoing bone marrow transplantation. No guideline was possible for any other agent reviewed due to inadequate and/or conflicting evidence.

CONCLUSIONS

None of the agents reviewed was determined to be effective for the prevention or treatment of OM. Two agents, pilocarpine and pentoxifylline, were determined to be ineffective, in the populations listed above. Additional well-designed research is needed on other interventions.

Interventions for preventing oral mucositis for patients with cancer receiving treatment

BACKGROUND

Treatment of cancer is increasingly more effective but is associated with short and long term side effects. Oral side effects remain a major source of illness despite the use of a variety of agents to prevent them. One of these side effects is oral mucositis (mouth ulcers).

OBJECTIVES

To evaluate the effectiveness of prophylactic agents for oral mucositis in patients with cancer receiving treatment, compared with other potentially active interventions, placebo or no treatment.

SEARCH STRATEGY

Electronic searches of Cochrane Oral Health Group and PaPaS Trials Registers (to 16 February 2011), CENTRAL (The Cochrane Library 2011, Issue 1), MEDLINE via OVID (1950 to 16 February 2011), EMBASE via OVID (1980 to 16 February 2011), CINAHL via EBSCO (1980 to 16 February 2011), CANCERLIT via PubMed (1950 to 16 February 2011), OpenSIGLE (1980 to 2005) and LILACS via the Virtual Health Library (1980 to 16 February 2011) were undertaken. Reference lists from relevant articles were searched and the authors of eligible trials were contacted to identify trials and obtain additional information.

SELECTION CRITERIA

Randomised controlled trials of interventions to prevent oral mucositis in patients receiving treatment for cancer.

DATA COLLECTION AND ANALYSIS

Information regarding methods, participants, interventions, outcome measures, results and risk of bias were independently extracted, in duplicate, by two review authors. Authors were contacted for further details where these were unclear. The Cochrane Collaboration statistical guidelines were followed and risk ratios calculated using random-effects models.

MAIN RESULTS

A total of 131 studies with 10,514 randomised participants are now included. Overall only 8% of these studies were assessed as being at low risk of bias. Ten interventions, where there was more than one trial in the meta-analysis, showed some statistically significant evidence of a benefit (albeit sometimes weak) for either preventing or reducing the severity of mucositis, compared to either a placebo or no treatment. These ten interventions were: aloe vera, amifostine, cryotherapy, granulocyte-colony stimulating factor (G-CSF), intravenous glutamine, honey, keratinocyte growth factor, laser, polymixin/tobramycin/amphotericin (PTA) antibiotic pastille/paste and sucralfate.

AUTHORS' CONCLUSIONS

Ten interventions were found to have some benefit with regard to preventing or reducing the severity of mucositis associated with cancer treatment. The strength of the evidence was variable and implications for practice include consideration that benefits may be specific for certain cancer types and treatment. There is a need for further well designed, and conducted trials with sufficient numbers of participants to perform subgroup analyses by type of disease and chemotherapeutic agent.

Interventions for preventing oral mucositis for patients with cancer receiving treatment

BACKGROUND

Treatment of cancer is increasingly more effective but is associated with short and long term side effects. Oral side effects remain a major source of illness despite the use of a variety of agents to prevent them. One of these side effects is oral mucositis (mouth ulcers).

OBJECTIVES

To evaluate the effectiveness of prophylactic agents for oral mucositis in patients with cancer receiving treatment, compared with other potentially active interventions, placebo or no treatment.

SEARCH STRATEGY

Electronic searches of Cochrane Oral Health Group and PaPaS Trials Registers (to 1 June 2010), CENTRAL (The Cochrane Library 2010, Issue 2), MEDLINE via OVID (1950 to 1 June 2010), EMBASE via OVID (1980 to 1 June 2010), CINAHL via EBSCO (1980 to 1 June 2010), CANCERLIT via PubMed (1950 to 1 June 2010), OpenSIGLE (1980 to 2005) and LILACS via the Virtual Health Library (1980 to 1 June 2010) were undertaken. Reference lists from relevant articles were searched and the authors of eligible trials were contacted to identify trials and obtain additional information.

SELECTION CRITERIA

Randomised controlled trials of interventions to prevent oral mucositis in patients receiving treatment for cancer.

DATA COLLECTION AND ANALYSIS

Information regarding methods, participants, interventions, outcome measures, results and risk of bias were independently extracted, in duplicate, by two review authors. Authors were contacted for further details where these were unclear. The Cochrane Collaboration statistical guidelines were followed and risk ratios calculated using random-effects models.

MAIN RESULTS

A total of 131 studies with 10,514 randomised participants are now included. Nine interventions, where there was more than one trial in the meta-analysis, showed some statistically significant evidence of a benefit (albeit sometimes weak) for either preventing or reducing the severity of mucositis, compared to either a placebo or no treatment. These nine interventions were: allopurinol, aloe vera, amifostine, cryotherapy, glutamine (intravenous), honey, keratinocyte growth factor, laser, and polymixin/tobramycin/amphotericin (PTA) antibiotic pastille/paste.

AUTHORS' CONCLUSIONS

Nine interventions were found to have some benefit with regard to preventing or reducing the severity of mucositis associated with cancer treatment. The strength of the evidence was variable and implications for practice include consideration that benefits may be specific for certain cancer types and treatment. There is a need for further well designed, and conducted trials with sufficient numbers of participants to perform subgroup analyses by type of disease and chemotherapeutic agent.

Interventions for preventing oral mucositis for patients with cancer receiving treatment

BACKGROUND

Treatment of cancer is increasingly more effective but is associated with short and long-term side effects. Oral side effects remain a major source of illness despite the use of a variety of agents to prevent them. One of these side effects is oral mucositis (mouth ulcers).

OBJECTIVES

To evaluate the effectiveness of prophylactic agents for oral mucositis in patients with cancer receiving treatment, compared with other potentially active interventions, placebo or no treatment.

SEARCH STRATEGY

The Cochrane Oral Health Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE were searched. Reference lists from relevant articles were scanned and the authors of eligible studies were contacted to identify trials and obtain additional information. Date of most recent searches: April 2004.

SELECTION CRITERIA

Trials were selected if they met the following criteria: design - random allocation of participants; participants - anyone with cancer receiving chemotherapy or radiotherapy treatment for cancer; interventions - agents prescribed to prevent oral mucositis; outcomes - prevention of mucositis, pain, amount of analgesia, dysphagia, systemic infection, length of hospitalisation, cost and patient quality of life.

DATA COLLECTION AND ANALYSIS

Information regarding methods, participants, interventions and outcome measures and results were independently extracted, in duplicate, by two review authors. Authors were contacted for details of randomisation and withdrawals and a quality assessment was carried out. The Cochrane Oral Health Group statistical guidelines were followed and risk ratios (RR) calculated using random-effects models.

MAIN RESULTS

Two hundred and two studies were eligible. One hundred and thirty two were excluded for various reasons, usually as there was no useable information on mucositis. Of the 71 useable studies all had data for mucositis comprising 5217 randomised patients. Interventions evaluated were: acyclovir, allopurinol mouthrinse, aloe vera, amifostine, antibiotic pastille or paste, benzydamine, beta carotene, calcium phosphate, camomile, chlorhexidine, clarithromycin, folinic acid, glutamine, GM-CSF, honey, hydrolytic enzymes, ice chips, iseganan, keratinocyte GF, misonidazole, oral care, pentoxifylline, povidone, prednisone, propantheline, prostaglandin, sucralfate, traumeel and zinc sulphate. Of the 29 interventions included in trials, 10 showed some evidence of a benefit (albeit sometimes weak) for either preventing or reducing the severity of mucositis. Interventions where there was more than one trial in the meta-analysis finding a significant difference when compared with a placebo or no treatment were: amifostine which provided minimal benefit in preventing moderate and severe mucositis RR = 0.84 (95% confidence interval (CI) 0.75 to 0.95) and 0.60 (95% CI 0.37 to 0.97), antibiotic paste or pastille demonstrated a moderate benefit in preventing mucositis RR = 0.87 (95% CI 0.79 to 0.97), hydrolytic enzymes reduced moderate and severe mucositis with RRs = 0.52 (95% CI 0.36 to 0.74) and 0.17 (95% CI 0.06 to 0.52), and ice chips prevented mucositis at all levels RR = 0.63 (95% CI 0.44 to 0.91), 0.43 (95% CI 0.23 to 0.81), 0.27 (95% CI 0.11 to 0.68). Other interventions showing some benefit with only one study were: benzydamine, calcium phosphate, honey, oral care protocols, povidone and zinc sulphate. The number needed to treat (NNT) to prevent one patient experiencing moderate or severe mucositis over a baseline incidence of 60% for amifostine is 10 (95% CI 7 to 33), antibiotic paste or pastille 13 (95% CI 8 to 56), hydrolytic enzyme 4 (95% CI 3 to 6) and ice chips 5 (95% CI 3 to 19). When the baseline incidence is 40%/90% the NNTs for amifostine are 16/7, for antibiotic paste or pastille 19/7, for hydrolytic enzyme 5/3 and for ice chips 7/3. The general reporting of RCTs was poor. However, the assessments of the quality of the randomisation improved when the authors provided additional information.

AUTHORS' CONCLUSIONS

Several of the interventions were found to have some benefit at preventing or reducing the severity of mucositis associated with cancer treatment. The strength of the evidence was variable and implications for practice include consideration that benefits may be specific for certain cancer types and treatment. There is a need for well designed and conducted trials with sufficient numbers of participants to perform subgroup analyses by type of disease and chemotherapeutic agent.

Chemotherapy- and Radiotherapy-Induced Oral Mucositis: Review of Preventive Strategies and Treatment

Oral mucositis is a frequently encountered and potentially severe complication associated with administration of chemotherapy and radiotherapy. Although many pharmacologic interventions have been used for the prevention and treatment of oral mucositis, there is not one universally accepted strategy for its management. Most preventive and treatment strategies are based on limited, often anecdotal, clinical data. Basic oral hygiene and comprehensive patient education are important components of care for any patient with cancer at risk for development of oral mucositis. Nonpharmacologic approaches for the prevention of oral mucositis include oral cryotherapy for patients receiving chemotherapy with bolus 5-fluorouracil, and low-level laser therapy for patients undergoing hematopoietic stem cell transplantation. Chlorhexidine, amifostine, hematologic growth factors, pentoxifylline, glutamine, and several other agents have all been investigated for prevention of oral mucositis. Results have been conflicting, inconclusive, or of limited benefit. Treatment of established mucositis remains a challenge and focuses on a palliative management approach. Topical anesthetics, mixtures (also called cocktails), and mucosal coating agents have been used despite the lack of experimental evidence supporting their efficacy. Investigational agents are targeting the specific mechanisms of mucosal injury; among the most promising of these is recombinant human keratinocyte growth factor.

Neurotoxic complications of chemotherapy in patients with cancer: clinical signs and optimal management

Neurotoxic side effects of chemotherapy occur frequently and are often a reason to limit the dose of chemotherapy. Since bone marrow toxicity, as the major limiting factor in most chemotherapeutic regimens, can be overcome with growth factors or bone marrow transplantation, the use of higher doses of chemotherapy is possible, which increases the risk of neurotoxicity. Chemotherapy may cause both peripheral neurotoxicity, consisting mainly of a peripheral neuropathy, and central neurotoxicity, ranging from minor cognitive deficits to encephalopathy with dementia or even coma. In this article we describe the neurological adverse effects of the most commonly used chemotherapeutic agents. The vinca-alkaloids, cisplatin and the taxanes are amongst the most important drugs inducing peripheral neurotoxicity. These drugs are widely used for various malignancies such as ovarian and breast cancer, and haematological cancers. Chemotherapy-induced neuropathy is clearly related to cumulative dose or dose-intensities. Patients who already have neuropathic symptoms due to diabetes mellitus, hereditary neuropathies or earlier treatment with neurotoxic chemotherapy are thought to be more vulnerable for the development of chemotherapy-induced peripheral neuropathy. Methotrexate, cytarabine (cytosine arabinoside) and ifosfamide are primarily known for their central neurotoxic side effects. Central neurotoxicity ranges from acute toxicity such as aseptic meningitis, to delayed toxicities comprising cognitive deficits, hemiparesis, aphasia and progressive dementia. Risk factors are high doses, frequent administration and radiotherapy preceding methotrexate chemotherapy, which appears to be more neurotoxic than methotrexate as single modality. Data on management and neuroprotective agents are discussed. Management mainly consists of cumulative dose-reduction or lower dose-intensities, especially in patients who are at higher risk to develop neurotoxic side effects. None of the neuroprotective agents described in this article can be recommended for standard use in daily practise at this moment, and further studies are needed to confirm some of the beneficial effects described.

Peripheral neuropathy associated with weekly oral 5-fluorouracil, leucovorin and eniluracil

5-Fluorouracil (5-FU)-associated neurotoxicity is uncommon; symptoms may occur abruptly or more gradually during the course of chemotherapy. Peripheral neuropathy with 5-FU therapy has only rarely been reported. Two patients treated in a phase I trial of oral 5-FU, leucovorin and eniluracil, an inhibitor of dihydropyrimidine dehydrogenase (DPD), developed delayed onset symptoms of unsteady gait and reduced sensation in the legs. Magnetic resonance imaging scans of the brain and neurologic examination did not support a CNS basis for the condition. Electromyograms and nerve conduction studies revealed sensorimotor polyneuropathy. Other common etiologies of peripheral neuropathy were excluded. The neurological condition of these patients stabilized after 5-FU dose reduction and partial resolution gradually occurred when protocol therapy was stopped. Although CNS symptoms may rarely complicate 5-FU therapy, peripheral neuropathy is unexpected. Patients with DPD deficiency treated with conventional doses of 5-FU typically develop acute CNS toxicity shortly after therapy, accompanied by extremely high systemic exposure to 5-FU. Patients with normal 5-FU clearance may also experience CNS toxicity, particularly with high-dose schedules, and both parent drug and its catabolites may be contributory. Since DPD was profoundly inhibited during eniluracil therapy in these two patients, it is likely that 5-FU or its active metabolites were contributing factors to the peripheral neuropathy.

Treatment of liver metastases from colorectal cancer with hepatic artery occlusion, intraportal 5-fluorouracil infusion, and oral allopurinol. A randomized clinical trial

BACKGROUND

Regional therapy for colorectal liver metastases aimed at prolonging survival has not been tested fully in a randomized trial with untreated control subjects. This study explored the efficacy of temporary hepatic artery occlusion followed by intraportal infusion of 5-fluorouracil (5-FU) and oral allopurinol as biochemical modulators in prolonging the survival of patients with nonresectable liver metastases and no extrahepatic cancer.

METHODS

Eighty-four patients were considered for randomization, of whom 24 were excluded at laparotomy because of extrahepatic cancer (n = 17) or resectable lesions (n = 5). In two patients, no cancer was identified in the liver. Thirty-two patients were allocated to receive treatment, and 28 were allocated to receive no regional or systemic treatment. Six patients were excluded after randomization because of major protocol violations.

RESULTS

The median survival time for patients was 17 months (range, 0-66), and for control subjects, the median was 8 months (range, 0-31). Log rank analysis demonstrated a significant survival benefit for treatment versus no treatment (P = 0.0039). (In two patients, early death was due to toxicity from the wrong dose of 5-FU and the wrong route of administration, respectively; the mean and median survival were reduced by 1 month).

CONCLUSION

This study identified a treatment modality that prolongs survival in patients with nonresectable liver metastases and no extrahepatic metastases from colorectal cancer, suggesting that control subjects receiving no therapy may not be necessary in future randomized trials.

Unexpected neurotoxicity in dogs receiving a cyclophosphamide, dactinomycin, and 5-fluorouracil chemotherapy protocol

An inexpensive combination chemotherapy protocol containing cyclophosphamide, dactinomycin, and 5-fluorouracil was evaluated in dogs with carcinomas. Fifteen dogs were entered in this study, and there were 1 complete response and 2 partial responses among 12 evaluable dogs. However, 6 of 15 dogs (40%) developed neurotoxicity. The neurotoxicity of this protocol was compared with a previous 5-fluorouracil-containing protocol and found to be significantly higher. Due to the unacceptably high rate of neurotoxicity, this protocol cannot be recommended for use in dogs with cancer.

A dose-intensive regimen of 5-fluorouracil for the treatment of metastatic colorectal carcinoma

5-Fluorouracil (5-FU) was delivered in a dose-intensive schedule to 23 patients with metastatic or unresectable colorectal carcinoma. The schedule consisted of bolus single-dose 5-FU therapy 400 to 500 mg followed by 4-day infusion of 5-FU, 600 to 800 mg/m2/day, followed by a 17-day to 24-day infusion of 200 to 250 mg/m2/day. Partial remissions were seen in 22% of all eligible patients. Significant toxicity, including mucositis, diarrhea, and hand-foot syndrome, necessitated dose reductions in most patients. The authors conclude that 5-FU given in this moderately intensive schedule is associated with a moderate level of response, as easily achieved with more conventional schedules or with 5-FU-leucovorin combinations. Tumor responsiveness to dose intensive 5-FU regimens may be limited.

Multimodal biochemical modulation of 5-fluorouracil activity in advanced colorectal cancer with allopurinol, folinic acid and dipyridamol

It is now commonly accepted that the activity of 5-fluorouracil (5FU) may be potentiated by folinic acid (FA). Moreover dipyridamol (DIP) interacts with the pyrimidine salvage pathway of 5FU. In 28 patients with advanced colorectal cancer, in progression under FA-5FU, we continued treatment with FA-5FU plus DIP. FA 200 mg/m2/day. i.v. push was given before 5FU 766.52 mg/m2/day (mean dose), in 60 min infusion for 5 subsequent days. Cycle was repeated every 21 days. We noticed greater but not seriously increased toxicity by the addition of DIP. The addition of DIP did not change response rates; it seemed to increase response but not significantly.

Folinic acid plus high-dose 5-fluorouracil with allopurinol protection in the treatment of advanced colorectal carcinoma

Protection by prolonged administration of allopurinol against high-dose 5-fluorouracil (5-FU) administered with folinic acid in 74 patients with colorectal cancer was investigated. The dose of 5-FU was 700 mg/m2 per day for 5 days. Of 41 patients without previous chemotherapy, 1 had a complete response and 4 had partial responses (total 12%), 15 remained stable and 21 progressed. Mean duration of response was 7.4 (1.8-12.6) months. The most frequent toxicities were decreased granulocytes (13%), diarrhoea (37%), and stomatitis (35%), which were similar to the frequencies of other studies with lower doses of 5-FU without allopurinol. Prolonged administration of allopurinol thus gives some protection to patients with colorectal cancer who receive folinic acid plus high-dose 5-FU but responses were not better than those with conventional doses.

Salivary passage of 5-fluorouracil during continuous infusion

Plasmatic and salivary concentrations of 5-FU were investigated in ten patients given 5-day continuous infusions of 5-fluorouracil (5-FU) (1 g/m2/day). Measurable concentrations of salivary 5-FU were scattered ranging from 6 to 100 ng/ml. Between individual 5-FU concentrations in saliva and plasma the coefficient of correlation was low. The theoretically predicted ratios of 5-FU concentrations in saliva over those in plasma, calculated as a function of salivary pH, did not correlate with the observed ratios, the majority of which ranged between 0.1 and 0.5. Noteworthy, 8 of 10 patients exhibited a more or less pronounced increase in 5-FU salivary excretion during 5-day continuous i.v. infusions.

Effect on liver tumor growth in rats of allopurinol and 5-fluorouracil in combination with hepatic artery ligation

Rats with an experimental solitary liver tumor of a nitrosoguanidine-induced colonic adenocarcinoma were subjected to hepatic artery ligation (HAL) alone or in combination with 5-fluorouracil (5-FU) in three different doses, with or without the addition of allopurinol. The drugs were injected i.p. on 3 consecutive days before or after the HAL procedure. HAL alone significantly reduced the tumor growth compared with the control procedure (P less than 0.001). This observation was correlated with a significantly prolonged survival for the ligated animals (P less than 0.01). The administration of a low dose of 5-FU (15 mg/kg per day) in combination with allopurinol (100 mg/kg per day) enhanced tumor growth compared with that in animals treated with 5-FU only (P less than 0.01) or nontreated animals (P less than 0.05). A significant increase in survival was observed in animals given a high dose of 5-FU (60 mg/kg per day) after HAL compared with non-treated animals (P less than 0.001) as well as animals subjected to HAL alone (P less than 0.02). All animals receiving more than 15 mg/kg per day 5-FU before HAL succumbed within 10 days. The addition of allopurinol did not protect the animals against this mortality. These observations indicate that the effect of HAL followed by 5-FU is dose-dependent and that, at least in this treatment modality, allopurinol does not modulate the toxicity of 5-FU.