Therapy-related pure erythroid leukemia with hepatic infiltration and hemophagocytic syndrome

Autopsy findings of acute erythroid leukemia

Acute erythroid leukemia (AEL) is an exceedingly uncommon but distinct hematological malignancy that shows neoplastic proliferation of erythroid precursors with maturation arrest and no significant myeloblasts. We describe an autopsy case of this rare entity in a 62-year-old man with co-morbidities. He underwent a bone marrow (BM) examination for pancytopenia during the first outpatient department visit, which revealed an increased number of erythroid precursors with dysmegakaryopoiesis suggesting the possibility of Myelodysplastic syndromes (MDS). Thereafter, his cytopenia got worsened, warranting blood and platelet transfusions. Four weeks later on the second BM examination, AEL was diagnosed based on morphology and immunophenotyping. Targeted resequencing for myeloid mutations revealed TP53 and DNMT3A mutations. He was initially managed along febrile neutropenia with the stepwise escalation of antibiotics. He developed hypoxia attributed to anemic heart failure. Subsequently, he had hypotension and respiratory fatigue pre-terminally and succumbed to his Illness. A complete autopsy showed infiltration of various organs by AEL and leukostasis. Besides, there was extramedullary hematopoiesis, arterionephrosclerosis, diabetic nephropathy (ISN-RPS class II), mixed dust pneumoconiosis, and pulmonary arteriopathy. The histomorphology of AEL was challenging, and the differential diagnoses were many. Thus, this case highlights the autopsy pathology of AEL, an uncommon entity with a strict definition, and its relevant differentials.

Challenging Diagnosis of Pure Erythroid Leukemia: A Case Report and Literature Review

Pure erythroid leukemia (PEL) is an extremely rare type of acute myeloid leukemia (AML), accounting for fewer than 1% of all AML cases. A 72-year-old man presented with severe fatigue. His bone marrow aspiration contained myeloperoxidase negative abnormal cells that were aggregating and depicting epithelial adhesion, suggesting the possibility of solid tumor metastasis. His general condition deteriorated during medical diagnosis, and he died soon after starting chemotherapy. PEL appeared to be the definitive diagnosis after evaluating the histopathological findings, which were obtained after his death. With atypical morphological features, immunophenotypic and karyotypic approaches must be integrated for PEL assessment.

Pure Erythroid Leukemia Mimicking Ewing Sarcoma/Primitive Neuroectodermal Tumor in an Infant

Pure erythroid leukemia (PEL) is a rare type of acute myeloid leukemia (AML) with a very aggressive clinical course. Presentation as a myeloid/erythroid sarcoma is exceedingly rare. We describe an infantile PEL presenting as a multifocal myeloid sarcoma, clinically and pathologically mimicking Ewing sarcoma/PNET family of tumors. The patient died 8 weeks after the initial presentation due to widespread disease. Our case shows that PEL needs to be considered in the differential diagnosis of small round blue cell tumors in infancy. A meticulous workup including immunohistochemistry, flow cytometry, molecular, and cytogenetic studies was required to reach the diagnosis.

How unique is pure erythroid leukaemia? A retrospective analysis of seven cases and review of the literature

AIMS

Pure erythroid leukaemia (PEL) is a rare subtype of acute myeloid leukaemia (AML) and its clinicopathological features are not well-defined. The aim of this study was to describe the immunophenotypic, cytogenetic and clinical features of PEL and to compare these with cases of AML with ≥ 50% erythroblasts.

METHODS

Cases of PEL according to WHO morphological criteria diagnosed at three institutions from 1997 to 2013 were included. A comparison cohort comprised of AML with ≥ 50% erythroblasts. The clinical, histopathology, immunophenotypic and cytogenetic features of cases were analysed. We also reviewed the existing literature on PEL, and combined our cohort with previously reported cases of PEL in a pooled analysis.

RESULTS

There were seven cases of PEL diagnosed at our institutions. There was a high incidence of either prior chemoradiotherapy exposure or evolution from pre-existing myelodysplastic syndrome (MDS) (71%). The leukaemic blasts frequently expressed glycophorin C (100%), CD117 (83%) and were myeloperoxidase negative (83%). Complex karyotypes were present in 83% of cases. Median overall survival was 2.9 months. Compared with AML with ≥ 50% erythroblasts, cases of PEL demonstrated a higher incidence of adverse-risk cytogenetics (p=0.01) and prior exposure to chemoradiotherapy (p=0.01).

CONCLUSIONS

PEL appears to be a unique entity that is often secondary or therapy related, commonly features a complex karyotype and has a poor prognosis. It is morphologically and immunophenotypically distinct from other cases of AML with erythroid hyperplasia.