Patients with acute lymphoblastic leukemia (ALL) and high-grade lymphoma have a 10–20% risk of meningeal disease during induction and in remission when given standard-dose chemotherapy. This risk has been reduced to about 1% using intrathecal prophylaxis with cytarabine and methotrexate in addition to the systemic regimen of hyperfractionated cyclophosphamide, vincristine, doxorubicin and dexamethasone (hyperCVAD) alternating with high-dose methotrexate-cytarabine (MA). The discomfort and potential adverse events with frequent lumbar punctures may impair patient compliance. Liposomal cytarabine (Depocyt) is an intrathecal preparation of cytarabine with a prolonged half-life. Use of Depocyt could potentially reduce the number of lumbar punctures needed for routine neuroprophylaxis. We reviewed the tolerability and activity of Depocyt for neuroprophylaxis in 15 patients treated with the hyperCVAD regimen. The cohort included 12 males and 3 females of median age 48 years (range, 23–72 years) with precursor B-cell ALL (8), T-cell ALL (3), Burkitt lymphoma and HIV (2), Ph-positive ALL (1), and lymphoblastic lymphoma (1). The patients received a total of 65 cycles of systemic chemotherapy, 36 with hyperCVAD and 29 with MA. Depocyt was given IT or IO in 33 cycles, methotrexate IT in 5, and no intrathecal therapy in 27. When treated with Depocyt, patients also received dexamethasone pre- and postmedication.. The planned dose of Depocyt was 50 mg for all patients, but after one serious adverse event, the dose was reduced to 25 mg when administered by Omaya. Depocyt was instilled on a median of day 8 of the cycle (range, −4 to 13). To date, a meningeal relapse has not occurred in any of the patients. Although minor neurological events (transient headache or neckache) were not uncommon, there were two serious adverse events. One patient developed a severe but transient headache during the fourth cycle and was readmitted for pain control. A second patient received Depocyt four days prior to MA. Shortly after completing chemotherapy, this patient developed hyponatremia and somnolence. The neurological status normalized after several days with supportive care alone. Since leakage of Depocyt into the peripheral blood might cause myelosuppression, hematologic recovery was also assessed. There was a significant difference in time to ANC>500 (p=0.02) and platelets >20,000 (p=0.005) between hyperCVAD and MA cycles, so hematologic recovery was assessed separately for these regimens, as shown in the Table.
Median Day of Hematopoietic Recovery Cycle Outcome All Cycles Depocyt No IT PX MTX IT “1” indicates the platelet count did not fall below 20,000 during that cycle. HyperCVAD ANC>500 15 15 14 16.5 Plts>20,000 1 1 1 1 MA ANC>500 16 16 16 15 Plts>20,000 13 13 14 15
There were no significant differences in time to neutrophil or platelet recovery between neuroprophylaxis regimens. Three patients received cranial or craniospinal radiation to compete neuroprophylaxis prior to allogeneic stem cell transplantation without notable neurotoxicity after transplantation. We conclude that it is safe to use a single dose of Depocyt (50 mg IT or 25 mg IO) following completion of administration of chemotherapy (around Days 6 – 8) during each cycle of the hyperCVAD regimen. This approach should be studied in a randomized trial to further assess its efficacy in comparison to more frequent instillations of methotrexate/cytarabine.
Energy Metabolism of Human Leukemic Lymphocytes and Granulocytes
