Acute myeloid leukemia in SRP54-mutated congenital neutropenia.

SRP54 mutations have recently been implicated in congenital neutropenia (CN) and the in-frame deletion, p.Thr117del, is the most common pathogenic mutation reported. The largest study of SRP54-mutated CN to-date followed 23 patients for a median of 15 years. No patients developed a hematologic malignancy in that study. Given the known risk of leukemia in other CNs it is crucial to know whether patients with SRP54-mutated CN have an increased risk of leukemia. We report the first case of leukemia in a patient with SRP54-mutated CN. A 15-year-old male with SRP54-mutated CN (p.Thr117del) was diagnosed with acute myeloid leukemia with myelodysplasia-related changes on a screening bone marrow evaluation. Next generation sequencing of the leukemia cells identified CSF3R and RUNX1 mutations. These mutations commonly co-exist in CN-associated malignancies and suggest leukemogenesis in SRP54-mutated CN may occur in a similar manner to other CNs. He was successfully treated with CPX-351 followed by hematopoietic cell transplant (HCT) and remains in remission at a follow-up time of 9 months. Although conclusions from this single report must be limited, this has potentially significant implications for both screening and treatment practices for these patients, including the role and timing of HCT.