Acute myeloid leukaemia with endometrial involvement presenting as abnormal uterine bleeding

The spread of acute myeloid leukaemia (AML) outside of the blood or bone marrow is known as extramedullary involvement, and common sites include the skin, bone and lymph nodes. Here, we describe a case of AML presenting as abnormal uterine bleeding in a pre-menopausal patient. Complete blood count (CBC) was notable for anaemia, thrombocytopaenia and leucocytosis, prompting a stat blood smear that showed increased circulating blasts. Subsequent bone marrow biopsy and analysis confirmed an AML diagnosis, while histological examination of endometrial tissue revealed infiltrating cells positive for CD34, myeloperoxidase and CD117, consistent with AML. The patient was given oestrogen for uterine bleeding and chemotherapy, eventually achieving remission. She received additional chemotherapy following relapse and remains in her second round of remission. As shown in this case, physicians should be aware of potential leukaemic infiltration of non-haematopoietic tissues and maintain a low threshold for ordering a blood smear in the context of an abnormal CBC.