Tumor lysis syndrome prevention

Hydration (sodium loading) Y Prior to amphotericin or contrast dye administration tumor lysis syndrome prevention... 

RH is admitted to the pediatric oncology service. She is started on allopurinol and intravenous fluids with sodium bicarbonate to prevent tumor lysis syndrome. According to her risk status, she will receive a three-drug induction with vincristine, dexamethasone, and pegylated asparaginase. She also will receive intrathecal (IT) chemotherapy for CNS prophylaxis with methotrexate, cytarabine, and hydrocortisone. 

The primary goals of management of tumor lysis syndrome are (1) prevention of renal failure and (2) prevention of electrolyte imbalances. Thus the best treatment for tumor lysis syndrome is prophylaxis to enable delivery of cytotoxic therapy for the underlying malignancy. 

The primary goals of management of tumor lysis syndrome are (1) prevention of renal failure and (2) prevention of electrolyte imbalances. Thus the best treatment for tumor lysis syndrome is prophylaxis to enable delivery of cytotoxic therapy for the underlying malignancy. For patients who present with or develop tumor lysis syndrome despite prophylaxis, treatment goals include (1) decrease uric acid levels, (2) correct electrolyte imbalances, and (3) prevent compromised renal function. These goals should be achieved in a cost-effective manner. 

Prevention of tumor lysis syndrome generally is achieved by increasing the urine output and preventing accumulation of uric acid. Prophylactic strategies should begin immediately on presentation, preferably 48 hours prior to cytotoxic therapy. Treatment modalities primarily increase uric acid solubility, address electrolyte disturbances, and support renal output. 

Pharmacologic prevention strategies for tumor lysis syndrome are aimed at low- and high-risk patients (Fig. 96-7). Allopurinol is a xanthine oxidase inhibitor that is used for prevention only because it has no effect on preexisting elevated uric acid. Rasburicase is a recombinant form of urate oxidase that is useful for both prevention and treatment but is extremely expensive (Table 96-12). Although the approved dose is 0.2 mg/kg per day... 

In general, the MoAbs used in treating cancer are relatively well tolerated compared with conventional cytotoxic chemotherapy. The main adverse effect associated with rituximab use is infusion-related or hypersensitivity reactions. Patients may experience fever, rigors, dyspnea, hypotension, and rarely anaphylactoid reactions. Premedication with acetaminophen, diphenhydramine, and corticosteroids can reduce these reactions. Patients with significant tumor burden at the time of first treatment with rituximab may experience tumor lysis syndrome, and appropriate measures should be implemented to prevent this complication in these patients. 

HDAC infusions should be administered over 2-3 hours to decrease risk of CNS toxicity use steroid eyedrops during treatment and for 48 hours posttreatment to prevent conjunctivitis with HDAC Increased HDAC neurotoxicity in patients with impaired renal function dose reduction recommended frequent neurologic exams monitor creatinine avoid concurrent administration of nephrotoxic drugs Rapid cell kill may see tumor lysis syndrome with large tumor burden (WBC >100,000/mm3)... 

AUopurinol inhibits xanthine oxidase and prevents the synthesis of urate from hypoxanthine and xanthine. It is used to treat hyperuricemia in patients with gout and to prevent it in those with hematological malignancies about to undergo chemotherapy (acute tumor lysis syndrome). Even though underexcretion rather than overproduction is the underlying defect in most gout patients, allopurinol remains effective therapy. 

Allopurinol is contraindicated in patients who have exhibited serious adverse fffects or hypersensitivity reactions to the medication, and in nursing mothers and children, except those with malignancy or certain inborn errors of purine metabolism (e.g., Lesch-Nyhan syndrome). Allopurinol generally is used in complicated hyperuricemia (see above), to prevent acute tumor lysis syndrome, or in patients with hyperuricemia post-transplantation. If necessary, it can be used in conjunction with uricosuric agents. 

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