Transformation to BCR ABL1 Positive Chronic Myeloid Leukemia Following Salvage DHAP Therapy in Relapsed Refractory Classical Hodgkin Lymphoma: A Rare Case Report

Abstract

Objective: To describe an exceptionally rare occurrence of chronic myeloid leukemia developing in the setting of relapsed refractory classical Hodgkin lymphoma following multi line chemotherapy, and to highlight the associated diagnostic challenges, therapeutic limitations, and evidence-based management considerations. Design: Single patient observational case report. Subjects/Patients: A 22 year old male with nasopharyngeal classical Hodgkin lymphoma of mixed cellularity subtype who achieved initial complete metabolic remission but subsequently developed relapsed refractory disease and a concurrent myeloproliferative neoplasm. Methods: Detailed clinical history, treatment chronology, laboratory data, histopathologic findings, cytogenetic and molecular analyses including fluorescence in situ hybridization, and radiologic imaging were systematically reviewed and interpreted in accordance with CARE guideline recommendations and current international practice guidelines. Results: Initial combination chemotherapy resulted in complete metabolic response. The patient later developed metabolically active bilateral tonsillar disease refractory to multiple salvage regimens including cyclophosphamide etoposide dexamethasone hydroxyurea and dexamethasone high dose cytarabine cisplatin. Progressive leukocytosis led to bone marrow evaluation demonstrating marked myeloid hyperplasia with breakpoint cluster region Abelson murine leukemia viral oncogene homolog one rearrangement in ninety nine percent of cells, confirming chronic myeloid leukemia. Conclusion: This case illustrates an extremely rare coexistence of chronic myeloid leukemia in relapsed refractory classical Hodgkin lymphoma, emphasizing the need for comprehensive hematologic evaluation in refractory disease and supporting early integration of targeted therapies guided by molecular diagnostics.