Emperipolesis of Erythroid Cells in Acute Myeloid Leukaemia with Myelodysplasia-Related Changes: A Case Report and Literature Review

Emperipolesis, a cell-in-cell phenomenon, involves a viable cell being transiently internalized within another cell’s cytoplasm from which it can exit without damaging either cell. In this report, we discuss the rarity of the emperipolesis of erythrocytes and erythroblasts, instead of the more commonly observed neutrophils. We report the case of a 52-year-old Chinese male who presented with pancytopenia and 33% blasts. Multiple mutations were revealed, including DNMT3A K826R, RUNX1 F396fs159, BCOR Q1208fs8, BCORL1 S575*, and PHF6 H302R. The patient was diagnosed with acute myeloid leukemia, myelodysplasia-related changes (AML-MR), and was treated with azacitidine and venetoclax, followed by daunorubicin and cytarabine (DA 3+7). This case highlights the rare occurrence of emperipolesis involving erythroid cells in AML-MR. We conducted a literature review exploring emperipolesis using PubMed, with search terms consisting of “emperipolesis”, “megakaryocytes”, “erythrocyte”, “erythroblast”, “neutrophil” and “lymphocyte”. A total of 24 articles that observed erythroid emperipolesis were referenced in this review, including 7 relevant case reports/series.