A new case series illustrates the wide range of clinical, biochemical, and molecular genetic characteristics of systemic mastocytosis (SM). The series, published in the International Journal of Molecular Sciences, concludes that SM requires a multidisciplinary diagnostic approach to ensure appropriate individualized clinical management of patients.

“Through a case-based approach, we aimed to illustrate clinical and pathological features of SM, as well as diagnostic and therapeutic challenges,” the authors wrote.

“Despite the peculiar morphological and phenotypical anomalies of neoplastic [mast cells], a pathological diagnosis of SM on [bone marrow] biopsy may be challenging in the presence of another hematological neoplasm or when tissue tumor burden is low.”

The authors presented 4 cases, each with particular findings and characteristics that illustrate diagnostic challenges and the importance of laboratory findings for adequate patient management.

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In case 1, the differential diagnosis was particularly difficult given the presence of several concurrent entities, and immunohistochemistry was useful for determining the mast cell lineage and aberrant phenotype. In case 2, the diagnosis was challenging due to the presence of another hematological neoplasm, and in case 3 it was difficult due to a low tumor burden. In case 4, the lack of a KIT D816V mutation was an atypical finding given that it is common in patients with SM, but its absence does not rule out the diagnosis and SM was ultimately diagnosed in this patient.

Each case required a unique therapeutic strategy, further suggesting the usefulness of an integrated diagnostic approach using a variety of assessment methods to improve the classification of SM in each patient and help determine the most effective treatment plan.


Crupi F, Sordi B, Vanderwert F, et al. Histopathology and molecular genetics in systemic mastocytosis: implications for clinical management. Int J Mol Sci. 2022;23(15):8772. doi:10.3390/ijms23158772