Mast cell leukemia represents a high-risk form of systemic mastocytosis defined by a markedly elevated circulating neoplastic mast cell burden. This protocol covers the specific sub-population meeting the MCL histopathologic threshold on bone marrow evaluation, with or without a concurrent hematologic neoplasm.
MCL is defined by the presence of ≥20% neoplastic mast cells on a bone marrow aspirate. This threshold may be met with or without an associated hematologic neoplasm. Even when overt organ damage is absent, the poor prognosis of MCL warrants active treatment consideration.
The primary objectives are resolution of organ damage findings, meaningful reduction in bone marrow mast cell burden, and reduction in serum tryptase level. Responses must be sustained for a minimum of 12 weeks to satisfy established criteria for clinical improvement.
Cytoreductive therapy forms the basis of management for MCL. Several therapeutic strategies — including enrollment in a clinical trial — may be considered depending on patient eligibility and clinical context.
DOI: 10.6004/jnccn.2018.0088