Abstract
To see if buffy coat smear examination might be an alternative to bone marrow aspiration for predicting relapse, 98 consecutive bone marrow aspirates from 96 children with acute lymphoblastic leukemia were examined blind with buffy coat and peripheral blood from the same patients. The 28 bone marrow aspirates from children no longer on treatment were all normal, and routine aspirates would appear unjustified in these patients. Of the remaining marrows, 8 showed relapse but only 3 were not predicted from the peripheral blood and buffy coat. In no case was buffy coat superior to peripheral blood in the detection of bone marrow relapse. Routine bone marrow aspirates are an inefficient way of diagnosing relapse in acute lymphoblastic leukemia in childhood, despite their precision, and a prospective study is needed to determine their value.