RESUMEN
Chronic myelomonocytic leukemia (cmml) is an indolent disease in the category of myelodysplastic and myeloproliferative neoplasms, which can often evolve into acute leukemic neoplasms. Although cytogenetic abnormalities such as trisomy 8 or absence of chromosome Y are well known, few reports about cmml with trisomy 11 have been published. Here, we report a case of cmml with trisomy 11 as the sole chromosomal abnormality, resulting in a very poor outcome. Based on a bone marrow specimen, cmml-1 with trisomy 11 was diagnosed in a 79-year-old man presenting with anemia and atypical peripheral blood cells. Because of the patient's age, he was followed without receiving anticancer treatment. Two months after his diagnosis, the patient's leucocytosis and anemia rapidly worsened, with increasing numbers of immature peripheral cells, which was strongly suggestive of leukemic transformation. Because of acute kidney injury superimposed on chronic kidney disease that led to poor performance status, cytotoxic chemotherapy was not considered feasible, and the patient was transferred to a hospice care facility.