SEQUENTIAL DEVELOPMENT OF WILMS-TUMOR, T-CELL ACUTE LYMPHOBLASTIC-LEUKEMIA, MEDULLOBLASTOMA AND MYELOID-LEUKEMIA IN A CHILD WITH TYPE-1 NEUROFIBROMATOSIS - A CLINICAL AND CYTOGENETIC CASE-REPORT

In her 81/2 years of life, a girl with neurofibromatosis type 1 (NF1) developed four sequential primary malignant neoplasms: Wilms tumor, T- cell acute lymphoblastic leukemia, medulloblastoma and acute myeloid l eukemia. The last three tumors were characterized by chromosomal abnor malities non-randomly associated with that particular disease. There w as no evidence of germline p53 mutation or of mutation of p53 in the l ast two tumors. We hypothesize that an unusual mutation of the NF1 gen e in this child promoted growth in tissues where the normal or mutated NF-1 gene product is usually silent or growth inhibitory.