Clinical use of the bcr/abl probe test in the evaluation of chronic myeloid leukemia patients

CML is characterized by a reciprocal translocation between the abl and bcr genes on chromosomes 9 and 22 and is usually diagnosed by the presence of the Philadelphia (Ph1) chromosome.However, the translocation may also occur without the appearance of the Ph1 chromosome. In this study the diagnostic efficiency of the molecular hybridization assay was investigated in 227 patients using a probe specific for the bcr region of the gene. Gene rearrangements were observed in 96% of Ph1-positive cases and in 92% of the patients in whom no Ph1 chromosome could be detected by karyotype analysis. By using peripheral blood the assay is easy to perform and superior in sensitivity. Thus, it is recommended that this assay should be routinely used as anadjunct to classical cytogenetics.

Monosomy 7 myeloproliferative disease associated with neurofibromatosis type I: a case report

A 7-year-old girl with neurofibromatosis type I (NF1) was diagnosed to have monosomy 7 myeloproliferative disease (Mo 7-MPD). Of the benign and malignant tumors that are encountered with increased incidence in NF1, those originating from the neural crest are frequent. However, tumors that do not originate from the neural crest may also be seen and among these, myeloid leukemias are prominent. Studies on NF1 patients with Mo 7-MPD and juvenile chronic myeloid leukemia (JCML) have suggested the role of the NF1 gene in the leukemogenesis. The relationship between monosomy 7 and hematological malignancies is already known. These findings are in agreement with the multi-step development theory of cancer. In addition, our case is one of the very rare NF1 cases having father to daughter inheritance with a myeloid malignancy. We believe that cytogenetic and molecular genetic studies will contribute to further understanding of leukemogenesis.