An unusual case report of myelofibrosis following treatment for acute promyelocytic leukemia with myeloid sarcoma as the initial manifestation.

INTRODUCTION

Acute promyelocytic leukemia (APL) is a subtype of acute myeloid leukemia (AML), with myeloid sarcoma (MS) seldom occurring at onset. Myelofibrosis (MF) is a condition characterized by megakaryocytic proliferation and atypia with an array of clinical findings, but MF secondary to APL treatment is extremely rare. MF secondary occurring after treatment of APL with MS as the initial presentation has not been reported.

CASE REPORT: A 73-year-old male was admitted to our hospital in August 2016, presenting with a pain in his left shoulder, followed by right shoulder and bilateral hip pain. A progressive increase in a mass in the right sternoclavicular joint was also observed. After comprehensive examines, he was diagnosed as APL with MS as the initial manifestation in April 2017. The patient then underwent induction, consolidation, and maintenance therapies until August 2019 and achieved complete remission. However, twice examinations in December 2020 and September 2022 confirmed that MF was present.

CONCLUSION

This is the first case of MF secondary occurring after treatment of APL with MS. Early recognition of MS in APL patients is crucial for timely intervention and treatment initiation. Meticulous diagnostic work-up and careful monitoring during treatment are necessary to detect potential complications, which may significantly impact the patients' outcome. Also, a comprehensive management approach encompassing induction, consolidation, and maintenance therapies should be adopted to ensure optimal therapeutic responses and reduce the risk of recurrence or treatment-related complications.