Mesna versus hyperhydration for the prevention of cyclophosphamide-induced hemorrhagic cystitis in bone marrow transplantation

Efficacy of mesna for prevention of hemorrhagic cystitis after high-dose cyclophosphamide therapy

For these reasons, a definitive statement about the relative efficacy of mesna for prophylaxis of cyclophosphamide-associated HC in BMT patients cannot be made. Because HC is a frequent and potentially serious complication of high-dose cyclophosphamide therapy, the implementation of some preventive measure is mandatory in all patients. Unless medically contraindicated, provision of sufficient hydration and diuresis to maintain adequate high urine flow should be a component of all prophylactic regimens. It is unclear whether the addition of mesna therapy or bladder irrigation to intravenous hydration provides greater protection. Studies indicate that mesna probably has no adverse effect on engraftment. This is consistent with its chemistry and pharmacology, as the drug is hydrophilic and activated only in the kidneys. Thus, it is inactive in the bloodstream and unable to penetrate cell membranes and interfere with the action of cyclophosphamide. Although safety issues surrounding the use of mesna for prevention of cyclophosphamide-associated HC appear to have been resolved, efficacy issues must await the completion of further well-controlled comparative trials.

The response of the urinary bladder, urethra, and ureter to radiation and chemotherapy

A comprehensive review of the physiological and clinical response of the urinary bladder, ureter, and urethra to radiation and chemotherapy is presented. The clinical syndromes that follow therapy for cancer of the bladder, prostate, and cervix are reviewed in detail. Methods of assessing, scoring, and managing toxicity are discussed.

Prevention of hemorrhagic cystitis following allogeneic bone marrow transplant preparative regimens with cyclophosphamide and busulfan: role of continuous bladder irrigation

High dose cyclophosphamide and/or busulfan conditioning treatment of recipients of bone marrow transplants proved to be highly effective but associated with substantial and sometimes life threatening hemorrhagic cystitis. To prevent this complication, a prophylactic continuous bladder irrigation program was instituted in patients receiving cyclophosphamide and/or busulfan in preparation for bone marrow transplantation. Retrospective analysis of 199 patients who underwent allogeneic bone marrow transplantation revealed that continuous bladder irrigation significantly decreased the frequency of hemorrhagic cystitis in patients receiving busulfan and cyclophosphamide (continuous bladder irrigation 23% versus no bladder irrigation 53%, p < 0.004). There was no difference in the frequency of hemorrhagic cystitis between the different preparative regimens in patients who underwent continuous bladder irrigation. There was no relationship between the incidence of hemorrhagic cystitis and the severity of graft-versus-host disease or the time to engraftment. The duration of hemorrhagic cystitis and overall survival rates were similar in both groups, and there was no increase in complications related to catheterization. In general, continuous bladder irrigation was well tolerated, decreased the incidence of hemorrhagic cystitis and may be useful in bone marrow transplant patients.

Treatment of cyclophosphamide-induced hemorrhagic cystitis with prostaglandins

OBJECTIVE

To report a case of cyclophosphamide-induced hemorrhagic cystitis, discuss prevention, and review treatment options, particularly the use of intravesicular prostaglandins.

DATA SOURCES

Literature obtained through a computerized search, with subsequent bibliography scanning. Information on the individual case was obtained from the patient's medical record and the Pharmacy Clinical Research Specialist.

CASE SUMMARY

A 29-year-old woman who had a postallogeneic bone marrow transplantation was hospitalized because of graft-versus-host disease. During hospitalization, she developed a cyclophosphamide-induced hematuria that, despite hydration and transfusions of blood products, progressed to refractory hemorrhagic cystitis. A response was prompted ultimately by a regimen consisting of continuous bladder irrigation and intermittent intravesical instillation of carboprost.

DISCUSSION

The best treatment for hemorrhagic cystitis remains prevention. Therapies for established cystitis are varied; the choice depends on the degree of hematuria present. Therapies are often temporary or ineffective, and themselves cause significant morbidity. One promising treatment option involves the intravesicular administration of prostaglandins. Reports in the literature discuss a variety of products, dosages, and treatment schedules that have been used with some success. The available data on this technique are presented.

CONCLUSIONS

Prostaglandins appear to be effective in resolving established hemorrhagic cystitis; however, their place in therapy remains unclear. Before this class can be employed routinely, several basic issues remain. These include optimal dosage, dosing schedule, duration of treatment, and comparative efficacy with other agents.

Clinical pharmacokinetics of cyclophosphamide

Cyclophosphamide has been in clinical use for the treatment of malignant disease for over 30 years. It remains one of the most useful anticancer agents, and is also widely used for its immunosuppressive properties. Cyclophosphamide is inactive until it undergoes hepatic transformation to form 4-hydroxycyclophosphamide, which then breaks down to form the ultimate alkylating agent, phosphoramide mustard. Sensitive and specific methods are now available for the measurement of cyclophosphamide, its metabolites and its stereoisomers in plasma and urine. The pharmacokinetics of cyclophosphamide have been understood for many years; those of the cytotoxic metabolites have been described more recently. The pharmacokinetics are not significantly altered in the presence of hepatic or renal insufficiency. As activity resides exclusively in the metabolites, whose pharmacokinetics are not predicted by those of the parent compound, correlations between cyclophosphamide pharmacokinetics and pharmacodynamics have not been demonstrated. Cyclophosphamide is used in doses that range from 1.5 to 60 mg/kg/day. A steep dose-response curve exists, and reductions in dose can lead to unfavourable outcomes. Myelosuppression is the dose-limiting toxicity, although in the setting of bone marrow transplantation, escalation beyond that dosage range is limited by cardiac toxicity. Longer term complications of cyclophosphamide therapy include infertility and an increased incidence of second malignancies. Cellular sensitivity to cyclophosphamide is a function of cellular thiol concentration, metabolism by aldehyde dehydrogenases to form inactive metabolites, and the ability of DNA to repair alkylated nucleotides. Whether alteration of these cellular functions will lead to further improvements in clinical outcomes is an area of active investigation.