Morphologic, immunologic and cytogenetic studies in erythroleukaemia: evidence for multilineage involvement and identification of two distinct cytogenetic‐clihicopathological types

Abstract

Clinical features, as well as morphology, immunophenotype and cytogenetics were retrospectively studied in 20 patients with an original diagnosis of erythroleukaemia (EL) reclassified according to the FAB criteria. Fifteen patients had de novo EL, five patients had therapy-related EL. Myelodysplasia preceded the onset of EL in eight cases and myelodysplastic features involving multiple haemopoietic lineages were observed at leukaemia presentation in all cases. Immunologic findings confirmed multilineage involvement, showing sub-population of cells expressing platelet-associated markers in more than 50% of cases tested and the presence of a myelomonocytic component, besides glycophorin A-positive cells. Cytogenetically, major karyotype aberrations (MAKA), defined by the presence of three or more aberrant events in the same clone, were observed in 14 cases, minor karyotype aberrations (MIKA) were observed in four cases and normal karyotype in two cases. No differences in the cytological-cytogenetic picture of our patients with de novo EL, and with therapy-related EL were found suggesting that aetiological factors and/or pathogenetic mechanisms common to EL and secondary leukaemia may exist. All patients with MAKA had leftward shift of erythropoiesis with proerythroblasts and basophilic erythroblasts usually representing more than 50% of all erythroid cells. In patients with MIKA or normal karyotype, maturatio of erythroid cells, though morphologically abnormal, was quantitatively preserved and early erythroblasts never exceeded 25% of erythroid cells. Clinically, the haemoglobin level at presentation, as well as in the proportion of patients achieving complete remission after chemotherapy, appeared to be lower in the maturation arrest-MAKA group as compared to the preserved maturation-MIKA/normal karyotype group. Median survival was shorter in the former group (3.5 months) than in the latter (median 13 months). Morphologic-immunologic-cytogenetic studies thus allow for the identification of two distinct cytogenetic-clinicopathological types of EL.

Hematopoietic stem cell transplantation for de novo erythroleukemia: a study of the European Group for Blood and Marrow Transplantation (EBMT)

“…This is consistent with previous studies in which no specific pattern was found. In our series, involvement of chromosomes 5 or 7 was observed in 6 patients; these abnormalities were also found in other series of patients with EL 9,15,26,30,41 and were associated with poor prognosis. 15 Trisomy 8 was observed in 6 patients and reported in previous series of patients with EL.…”

“…15 Trisomy 8 was observed in 6 patients and reported in previous series of patients with EL. 9,15,30 These abnormalities on chromosomes 5, 7, and 8 are also described in MDS. 42 We conclude that patients with EL who achieve CR1 should proceed to HLA matched allogeneic HSCT if a family donor is available.…”

Erythroleukemia: a need for a new definition

“…However, for other authors, more than the percentage of erythroblasts, cytogenetic abnormalities correlate with the rate of CR. 12,17,21,22 Age is an important factor; older patients have a low CR and a short survival. Expression of P-glycoprotein is clearly a poor factor of survival.…”

Pure Erythroleukemia (Variant Acute Myeloid Leukemia-vAML-M6) with Deletion of Chromosome 20, Mainly Presenting as Late Erythroblasts, a Unique Case Report with Review of Literature

“…The percentage of pronormoblast seems an important factor of survival according to Kowal-Vern et al [16] with a mean survival of 34 months in AML6a, 3.5 months in AML6b and 10.5 months for AML6c. However, for other authors, more than the percentage of erythroblasts, cytogenetic abnormalities correlate with the rate of CR [13,[17][18][19]. Age is an important factor; older patients have a low CR and a short survival.…”