Therapy-related acute myeloid leukemia with a rare complex karyotype following first-line therapy for small cell lung cancer: A case report.

Therapy-related acute myeloid leukemia (t-AML) following chemotherapy in patients with small cell lung cancer (SCLC) is rare, and its clinical and genetic characteristics remain poorly elucidated. In the present study, a 53-year-old male patient with SCLC is reported. After diagnosis in June 2023, the patient received 9 cycles of etopside and cisplatin (EP) chemotherapy, 7 cycles of EP plus durvalumab and 1 cycle of etoposide plus durvalumab sequentially. Hematological abnormalities developed 23 months after the initial chemotherapy. Bone marrow aspiration revealed 28% blasts, and flow cytometry identified 36.4% abnormal myeloid blasts. Chromosomal karyotype analysis displayed 46,XY,t(11;20)(p15; q11) [7]/46,idem,add(6)(p25)[13], consistent with a diagnosis of t-AML (M2). The present case represents t-AML with a rare karyotype and extreme latency following treatment for SCLC. The present case report enriches the available genetic spectrum of t-AML associated with SCLC, suggesting the necessity for long-term hematological monitoring in patients with SCLC and provides a reference for the clinical management of dual malignancies.