Secondary acute myelomonocytic leukemia in untreated follicular lymphoma: A case report

Follicular lymphoma (FL) is an indolent B-cell neoplasm associated with an increased risk of secondary malignancies. Although these usually occur after cytotoxic therapy, we encountered a rare case of secondary acute myelomonocytic leukemia (AMMoL) developing without prior chemotherapy. We present the case of a man in his 70s undergoing maintenance dialysis, who was diagnosed with grade 1 FL during a pre-operative evaluation for gastric endoscopic submucosal dissection. After 8 months, he presented with AMMoL without prior exposure to chemotherapy. Intensive chemotherapy was avoided because of advanced age and poor cardiac function, and supportive care was provided. This report describes an exceptionally early onset of secondary AMMoL during the observation period, only 8 months after the diagnosis of FL. Continuous laboratory and clinical surveillance is essential for the early detection of secondary hematologic disorders, even in patients managed conservatively.