CD30 expression in high-risk acute myeloid leukemia and myelodysplastic syndromes

We assessed for CD30 expression in patients with acute myeloid leukemia (AML) or high-grade myelodysplastic syndrome (MDS) to examine the possibility that anti-CD30 could be targeted therapy in these patients.

Multicolor flow cytometry immunophenotypic analysis was performed on bone marrow aspirates of 135 patients with AML or MDS and peripheral blood samples in a subset of 33 patients. Immunohistochemistry was performed on bone marrow aspirate clot specimens of 84 patients.

The median patient age was 63 years (range, 13-92 years); 102 (75%) patients had refractory or recurrent disease, and 68 (50%) had high-risk cytogenetics. Overall, the median percentage of blasts positive for CD30 was 14% (range, 0%-91%). By using an arbitrary 20% cutoff, 49 (36%) patients were considered to have CD30 expression. Monocytic cells, either mature or immature, were consistently negative for CD30. Therefore, CD30 expression was less in AML with monocytic differentiation (P = .006). The patients with persistent disease who had been actively treated had a higher level of CD30 expression than the patients who were untreated (P = .031). In paired samples, CD30 expression was consistently higher in bone marrow blasts than in peripheral blood blasts (P = .002). Immunohistochemistry demonstrated CD30 expression by myeloblasts in a subset of patients, but reactivity was generally weaker and focally compared.

CD30 is expressed by myeloblasts in a substantial subset of patients with AML or MDS. Because the study group was composed mostly of patients with high-risk AML or MDS in whom very few treatment options are available, these data raise the possibility that anti-CD30-targeted therapy could be a potential option for this patient group.