Morphologic and cytochemical characterization of adult lymphoid leukemias which express myeloid antigen
Davey, F.R.; Mick, R.; Nelson, D.A.; MacCallum, J.; Sobol, R.E.; Royston, I.; Cuttner, J.; Ellison, R.R.; Bloomfield, C.D.
Leukemia 2(7): 420-426
1988
ISSN/ISBN: 0887-6924 PMID: 3164798 Document Number: 308213
Cancer and Leukemia Group B demonstrated that adults with acute lymphoid leukemia (ALL) possessing blast cells with myeloid antigens (My+ ALL), as identified by monoclonal antibodies against CD13 and CD33, have a worse prognosis than those lacking myeloid antigens (My- ALL). Consequently, we further studied this group of adults with ALL to determine if these immunological groups could be distinguished by morphological and cytochemical criteria. Bone marrow films were classified according to French-American-British Co-operative Group Criteria, assessed for myelodysplasia, and examined for blasts with azurophilic granules. More cases of My+ ALL had L2 morphology than did My- ALL (68% vs. 49%, p = 0.04), and more cases of My+ ALL were positive for acid .alpha.-naphthyl acetate esterase (61% vs. 31%, p = 0.03). The presence of myelodysplastic changes was not significantly different in My+ ALL (13%) as compared to My-ALL (5%), but more cases of My+ ALL had unusual blasts (monocytoid features and cytoplasmic buds) than did My-ALL (19% vs. 0%, p < 0.01). In addition, more cases of My+ ALL had > 5% of the blasts with azurophilic granules (42% vs. 13%, p = 0.01). In the My+ ALL group the presence of azurophilic granules was associated with a longer median survival (13.5 months vs. 1.5 months vs. 1.5 months, p < 0.01). We conclude that My+ ALL can be suspected when cases possess L2 morphology, unusual blasts, positive staining for acid .alpha.-naphthyl acetate esterase, and > 5% azurophilic granules. In addition, the poor risk group (My+ ALL) can be further subdivided into better and poorer risk subgroups based on presence of azurophilic granules.