Long‐term serum copper studies in acute leukemia in children

The relationship of serum copper levels (SCL) and bone marrow blast cells over a major period of the disease has been studied in 25 cases of acute leukemia in children. Serum copper showed positive correlation with blast cells in 61% of all paired data. Special groups provided more definitive and clinically valuable data, however. In the initial treatment period (30 days), the positive correlation of SCL with bone marrow blasts was 100%, falling to 57% over extended periods. In remission, 77% of paired values were correlated. In evaluating the occasions of non‐correlation in bone marrow remission, central nervous system leukemic involvement was most prominent, with infection, viral and bacterial, and lymphoma being also coincident clinical conditions believed to be related to the high SCL. Such findings tend to support the general hypothesis that SCL is reflecting extensive, perhaps abnormal cellular proliferation. Evaluation of the terminal portion of five cases confirmed the clinical impression of generally poor correlation of SCL and bone marrow blasts in the terminal portion of acute leukemia. The findings in this study point particularly to the value of SCL both in evaluation of initial therapy response, and as a possible index of extramedullary neoplastic activity.