Chronic lymphocytic leukemia (CLL) is the most common form of leukemia in adults and is a slowly progressing cancer of the blood and bone marrow. According to cancer statistics, an estimated 16,060 new CLL diagnoses will be made in the United States in 2012.1 Careful surveillance predicts the time point where treatment becomes necessary.
Bendamustine has a unique structure that acts as an alkylating agent, and DNA damage occurs in the cell, causing apoptosis. Bendamustine has been shown to be beneficial as frontline, salvage treatment in CLL, indolent B-cell non-Hodgkin lymphoma, and advanced multiple myeloma. Its mechanism of action may promote less drug resistance in the cell but is not fully understood.
Prior to infusion with bendamustine, the patient is given written information regarding drug delivery and side effects. On the day of treatment, the oncology case manager will review the written information, going over expected treatment side effects. Bendamustine is administered over 60 minutes at doses of 100 mg/m2 or 120 mg/m2 on days 1 and 2 of 21- or 28-day cycles.
Adverse reactions to bendamustine include pancytopenia, nausea, vomiting, fatigue, weakness, dry mouth, somnolence, cough, constipation, headache, stomatitis, and skin rash.2 Careful monitoring of blood counts, usually once per week, is recommended due to the possibility of pancytopenias in week 3. After the first cycle is complete, patient tolerability and blood count trend will be assessed and adjustments in treatment will be made prior to the next cycle.
Along with a complete blood count with differential, a chemistry panel should be done to monitor the patient’s renal and liver function, especially in patients with impairments. Due to susceptibility for infection, particularly if the patient has received previous treatment, the usual practice is to start antibiotic prophylaxis. A broad-spectrum antibiotic such as Bactrim DS or another similar antibiotic is prescribed. For an absolute neutrophil count of <500, and/or febrile neutropenia, growth factor support will be ordered at the next cycle. Blood or platelet transfusions are normally not needed, but in the case of significant hematological toxicity, transfusions may be given, and generally a dose reduction for the next cycle will be ordered. For nausea and vomiting prophylaxis, a long-acting antiemetic is given on day 1, and the patient is given a prescription for an oral antiemetic to be used as needed at home.
The probability of tumor lysis mandates precautionary treatment. The patient is started on allopurinol and given ample fluids at the first cycle. There is a possibility of an infusion reaction necessitating emergency medication, which would include an antihistamine, antipyretic, or corticosteroid. If a grade 1 or 2 reaction occurs, subsequent cycles would include routine administration of these medications.
With overall response rates as high as 77% and a reported duration of response from 6 to 12 months, bendamustine is a reasonable treatment and has tolerable toxicity even in pretreated patients. The key to successful and safe treatment is close supervision by the physician and reinforcement of patient education. The goal of treatment is to control disease and maintain a positive quality of life.
References
- American Cancer Society. Cancer Facts & Figures 2012. Atlanta, GA: American Cancer Society; 2012. www.cancer.org/acs/groups/content @epidemiologysurveilance/documents/document/acspc-031941.pdf. Accessed November 9, 2012.
- Hussar DA. New Drugs 09. www.nursingcenter.com/pdf.asp?AID=840623. Accessed November 8, 2012.