1988 Volume 29 Issue 11 Pages 2079-2085
We report in this paper a case of acute magakaryoblastic leukemia (AMKL) in Down syndrome accompanied by 3q-, showing tumor formation and myelofibrosis. The patient was an one and 9/12 year-old girl with Down syndrome. She was admitted to our hospital because of anemia and bleeding tendency.
On admission, emaciation, hepatosplenomegaly and generalized lymphadenopathy were dominant. Peripheral blood was pancytopenic and white blood cell count was 3,400/μl with 14% blasts. The blasts with fine granules on light microscopic study were negative for peroxidase, positive for ACP, and PAS stainings. On electron microscopic study, the blasts had α-granules and small amount of demarcation membranes, and were positive for platelet peroxidase staining. By bone marrow biopsy, myelofibrosis and an excessive proliferation of atypical megakaryocytes were noted. Chromosomal analysis of peripheral blood disclosed 47, XX, del (3)(q21) and 47, XX, +21, der (8) t(8;1)(q24:q12).
A diagnosis of AMKL was made, and prednisolone, vincristine, daunorubicin, cytosine arabinoside were administered, but they were not effective. A solid tumor appeared first at the right forehead at the age of two years, and then progressed to the upper and lower mandibulas, orbita and right thigh with an increase in size. She died of respiratory failure due to tumor obstruction when she was two and 3/12 years old. On post-mortem examination it was revealed that diffuse and nodular infiltrations of blast cells were detected in most of the visceral organs and bones, and formed tumors.
Recent investigation revealed that the incidence of abnormality of each NO. 21 and No. 3 chromosome is high in AMKL, but the case having chromosomal abnormalities of both No. 21 and No. 3 as presented here is not reported previously. It is sugested that the abnormalities of the two chromosomes are reflected by this paticular clinical course.
