ASTRO 2021: Use of Total Marrow and Lymphoid Irradiation Before Chemotherapy in AML
Posted: Friday, November 12, 2021
Total marrow and lymphoid irradiation combined with post-transplant cyclophosphamide and tacrolimus may result in improved graft-vs-host disease-free/relapse-free survival in patients with acute myeloid leukemia (AML). In addition, this regimen appeared to be associated with low toxicity and low nonrelapse mortality. Jeffrey Y.C. Wong, MD, of City of Hope National Medical Center in Duarte, California, presented these results at the 2021 American Society for Radiation Oncology (ASTRO) Annual Meeting (Abstract 159).
The trial enrolled 18 patients with AML in either their first or second complete remission. Patients were given 20 Gy of total marrow and lymphoid irradiation to bone, lymph nodes, spleen, and other organs. They then received a stem cell infusion, followed by 50 mg/kg/day of post-transplant cyclophosphamide and 1 mg of tacrolimus. The average mean dose administered to different organs was 8.1 Gy in the lungs, 7.5 Gy in the kidneys, 7.3 Gy in the heart, 4.4 Gy in the oral cavity, 6.4 Gy in the esophagus, 9.1 Gy in the upper gastrointestinal tract, 10.2 Gy in the lower gastrointestinal tract, and 10.0 Gy in the bladder.
The median follow-up for surviving patients (17 of 18) was 12.5 months. The overall survival rate at 1 year was estimated to be 100%, and the rate of relapse-free survival was 83.3%. The rate of disease relapse at 1 year was 16.7%. At both 100 days and 1 year, nonrelapse mortality was estimated to be 0%. Three patients developed disease relapse after transplantation (16.7%), and one patient died after relapse.
No grade 3 or 4 toxicities or toxicity-related deaths were reported. Two patients developed acute graft-vs-host disease, with one patient developing grade III to IV disease. An additional five patients developed chronic graft-vs-host disease; therefore, the 1-year chronic graft-vs-host disease rate was 28.6%. The graft-vs-host/relapse-free survival rate at 1 year was 60.6%.
Disclosure: For Dr. Wong’s disclosures, visit plan.core-apps.com.