Leukemia and lymphoma: what is the role for intrathecal prophylactic treatment in adults?

The final subject to be addressed is the role of prophylactic treatment for hematologic tumors. Prophylactic intrathecal therapy is the standard of care in pediatric acute lymphocytic leukemia patients. Should prophylaxis be applied to adult patients with leukemia? In addition and as an extension of the adult leukemia patient discussion, is there a role for intrathecal prophylaxis in patients with lymphoma, a population at risk for neoplastic meningitis?