Sanctuary therapy: a randomized trial of 724 children with previously untreated acute lymphoblastic leukemia: A Report from Children's Cancer Study Group

Abstract

Between 1972 and 1974, Childrens Cancer Study Group enrolled 724 children with newly diagnosed acute lymphoblastic leukemia on a single randomized clinical trial. Study CCG-101 was designed to test four types of presymptomatic central nervous system and sanctuary therapies consisting of (a) 2400-rad craniospinal radiation therapy (RT) plus 1200-rad extended-field RT, which included the liver, spleen, kidneys, lower abdomen, and gonads; (b) 2400-rad craniospinal RT; (c) 2400-rad cranial RT plus intrathecal methotrexate (i.t. MTX); and (d) i.t. MTX alone. Patients all received a 28-day induction course of vincristine, prednisone, and L-asparaginase and were maintained subsequently on a regimen consisting of daily 6-mercaptopurine, weekly MTX, and monthly pulses of vincristine and prednisone. Patients treated with six doses of i.t. MTX alone had a significantly higher incidence of central nervous system relapse than did patients treated with 2400-rad craniospinal RT plus 1200-rad abdominal RT, 2400-rad craniospinal RT, or 2400-rad cranial RT plus i.t. MTX. There was no significant differences in marrow remission duration or survival of the treatment groups. There appears to be a benefit with regard to length of bone marrow remission and survival for patients with initial white blood counts greater than or equal to 20,000/cu mm treated with cranial RT plus i.t. MTX. The majority of the patients remaining on study have now discontinued maintenance therapy. The 8-year overall estimated survival rate on this study is 56%, and the disease-free survival rate is 52%.