Minimally differentiated acute leukemia.
We have studied 35 adult patients with morphologically undifferentiated peroxidase-negative acute leukemia that failed to meet the criteria for acute lymphoblastic leukemia and compared them to patients with FAB M1-M7 seen by the same physicians. The diagnosis of minimally differentiated acute leukemia (MD-AL) was associated with a higher incidence of prior hematologic disease, lower WBC, fewer blood blasts, lower marrow cellularity and a tendency towards older age. Of all patients treated with AML since January 1983, those with MD-AL were less likely to get a complete remission than those with other subtypes (35 vs 64%, p = 0.03). Treatment failure was usually due to resistant disease. Analysis of outcome as a function of drugs used during induction therapy showed an advantage for regimens containing vincristine and prednisone. The leukemic blast cells of nine patients were immunophenotyped for myeloid, lymphoid and megakaryoblast/platelet antigens. Although there were too few for a full statistical analysis as was applied to the larger group of 35 patients with MD-AL, these patients had a lower bone marrow cellularity as compared to FAB M1-M7 and a low remission rate. Eight of these were found to have positive myeloid markers and met the criteria for FAB M0. We conclude that patients with MD-AL form a distinct group with characteristic presenting features and a low response rate. Outcome data suggest that vincristine and prednisone should be included in experimental induction programs.
Cadwell
F J
FJ
Department of Medicine, University of Iowa College of Medicine, Iowa City 52242.
Burns
C P
CP
Dick
F R
FR
Jones
M P
MP
Heckman
K D
KD
Weiner
G J
GJ
Goeken
J A
JA
D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D002454:Cell Differentiation / Q000502:physiology; D005260:Female; D006801:Humans; D016130:Immunophenotyping; D007938:Leukemia / Q000188:drug therapy / Q000401:mortality / Q000473:pathology*; D007951:Leukemia, Myeloid / Q000188:drug therapy / Q000401:mortality / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012074:Remission Induction; D012189:Retrospective Studies