Tumor cells from most forms of leukemia are relatively sensitive to radiation. However, radiation therapy still has a limited scope in treatment of leukemia, mainly due to the generalized growth of the disease.
Radiation may be a supplementary treatment for different types of leukemia. Treatment protocols for leukemia often include detailed indications for radiation therapy. There are guidelines for what patients and which organs are recommended for radiation therapy, definitions for target volume and risk organs, fractioning and total dose. Use of radiation is so protocol-dependent that general recommendations cannot be given.
Total brain or total CNS axis (brain with spinal cord and cerebrospinal fluid space) are the most common areas appropriate for radiation treatment with the goal of curing the disease. Radiation in these areas can be given as prophylaxis against or treatment for manifest CNS affection.
Patients with acute lymphocytic leukemia of testicles or with a large mediastinal tumor may also be appropriate for consolidating radiation treatment to these areas.
Radiation of the entire body (total body irradiation, TBI) may be part of the conditioning regimen before an allogeneic or autologous stem cell transplantation.
Radiation therapy to most regions may be appropriate as palliative treatment in situations where local progression of leukemia dominates the clinical picture.