Case Report of a DDX41 Germline Mutation in a Family with Multiple Relatives Suffering from Leukemia

Introduction: Previously, it was assumed that genetic influence played a minor role in acute myeloid leukemia (AML). Increasing evidence of germline mutations has emerged, such as DDX41 germline mutation associated with familial AML. Case presentation: A 64-year-old male patient presented with reduced exercise tolerance and shortness of breath. Following confirmation of AML diagnosis, the patient was enrolled into the AMLSG-30-18 study with a requirement for allogenic stem cell transplantation. The sister was initially selected as a fully HLA-matched donor. However, the family history showed risks for familial AML. Due to the striking family history, further diagnostic steps were initiated to detect a germline mutation. Methods: Using NGS in the patients' bone marrow AML sample, a DDX41 mutation with a VAF of 49% was detected, raising the possibility of a germline mutation. DNA from cheek swabs and eyebrows were tested for the presence of the DDX41 mutation in all siblings. Results: DDX41 germline mutation was detected in 5 out of 6 siblings. The sister was excluded as a related donor and the search for an unrelated donor was initiated. Conclusion: Obtaining family history of cancer patients plays a crucial role in oncology. If a germline mutation is suspected, further family work-up should be initiated.