Abstract
A patient with lymphoblastic lymphosarcoma, leukocytosis, eosinophilia, and granulocytic hyperplasia of the bone marrow was treated with chemotherapy and radiation with many changes in her clinical state but maintained a consistent chromosome abnormality in the bone marrow before and during treatment. A lymph node aspirate obtained before treatment showed the same abnormality. There were consistently two chromosomes missing, one each in group 6-12 and 13-15 respectively. These were replaced by two new chromosomes: one was very similar to pair 3 and the other was acrocentric and slightly longer than pair 21. The skin and peripheral blood leukocyte culture had a normal female karyotype. The leukemoid blood picture was differentiated from chronic myelocytic leukemia by the absence of the Ph1 chromosome, normal serum B12, and normal leukocyte alkaline phosphatase activity.