Systemic Mastocytosis: Diagnosis and Management in 2024


  • Stephanie Lee, MD, MSc, FRCPC Division of Hematology/Oncology, St. Michael's Hospital, Toronto, ON



Mastocytosis is a group of clonal disorders characterized by an accumulation of neoplastic mast cells (MCs) in one or more organ systems. The clinical presentation of mastocytosis is heterogenous as are the clinical outcomes. For example, some variants are associated with near normal life expectancy, while others are amongst the most aggressive known malignancies. Mastocytosis can occur in both pediatric and adult populations and can be classified into three major groups: systemic mastocytosis (SM), cutaneous mastocytosis (CM), and localized mast cell sarcoma. This review will focus on SM in adults with the aim of providing a general overview of the (1) pathophysiology, (2) diagnostic approach, and (3) current treatment landscape in Canada.

Author Biography

Stephanie Lee, MD, MSc, FRCPC, Division of Hematology/Oncology, St. Michael's Hospital, Toronto, ON

Dr. Lee received an MD from the University of British Columbia and completed internal medicine and hematology residency at the University of Toronto. She completed a fellowship in the Acute Leukemia and Myeloproliferative Neoplasms Program at the Princess Margaret Cancer Centre in Toronto followed by a MSc degree in Epidemiology and Clinical Research at Stanford University. She is currently a hematologist at St. Michael’s Hospital in Toronto and an Assistant Professor at the University of Toronto. She helped establish St. Michael’s Hospital as the only Canadian centre of excellence in mast cell disorders with the American Initiative in Mast Cell Diseases and is currently the primary investigator of the program at St. Michael’s Hospital.


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How to Cite

Lee S. Systemic Mastocytosis: Diagnosis and Management in 2024. Can Hematol Today [Internet]. 2024 Apr. 25 [cited 2024 Jul. 23];3(1):34–42. Available from: