High sensitivity and specificity assay for detection of leukemia/lymphoma cells in human bone marrow

An assay of high sensitivity and specificity for detection of residual malignant cells in remission bone marrow from patients with acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL) has been developed. The assay combines an immunoselection step with immunoglobulin gene rearrangement analysis by high specific-activity DNA probes. In experimental conditions, less than one contaminating tumor cell out of 1000 bone marrow cells was detected. A bone marrow contamination was detected in morphologically negative bone marrow specimens from two intermediate-grade non-Hodgkin's lymphoma patients. This method can be of value in determining a true remission status in high-risk ALL and NHL patients.