An extremely rare clinical occurrence has been recently reported in three patients—the coexistence of systemic mastocytosis (SM) and basal cell carcinoma (BCC).
The prognosis of individuals with the simultaneous presence of both disorders has not been well documented, so the study researchers sought to conduct a retrospective evaluation of the three patients with SM and concurrent BCC. Findings from their analysis were published recently in the American Journal of Clinical Pathology.
The three individuals with SM plus BMM were identified in the pathology database of the University of Pennsylvania between 2010 and 2023. All patient demographics, clinical features, histopathological characteristics and treatment outcomes were assessed.
Immunochemistry, histopathological evaluation, and C-KIT D816V mutation analysis were carried out on biopsies. Next-generation sequencing (NGS) was utilized to recognize other hematologic neoplasm–related mutations.
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Similarities and differences between the three patients
All three patients were female, ages 47 years, 50 years and 69 years. In all three cases, “atypical CD117+ tryptase+ CD25+ mast cells with mild to moderate pleomorphism were found in the dermis adjacent to the BCC cells.” There was bone marrow involvement reported in all three patients as well.
Mildly elevated serum tryptase concentrations were observed in all three patients. Moreover, all three individuals harbored a C-KIT D816V mutation and reported a history of systemic glucocorticoid use prior to being diagnosed with BCC.
One of the three patients had received treatment with phototherapy. Somatic mutations were detected among all three individuals via the utilization of NGS.
The first patient experienced many BCC relapses, although a subsequent bone marrow biopsy did not reveal any SM involvement.
The second patient was diagnosed with mast cell leukemia (MCL)—a form of SM. Despite MCL being associated with a poor prognosis, she has survived for several years since diagnosis.
The third patient was diagnosed with essential thrombocythemia—a rare chronic blood disorder—along with SM with an associated hematological neoplasm. Her symptoms have remained stable.
In all three individuals, treatments varied from surgical excision to anti-mastocytosis therapy. Favorable therapeutic outcomes were reported in all three patients.
“The coexistence of BCC with mastocytosis poses diagnostic challenges due to its infrequency and varied clinical presentations,” the investigators explained.
The use of certain SM treatments, including phototherapy and corticosteroids, has been acknowledged as a risk factor for the development of BCC.
“[R]ecognizing this unique combination [of disorders] in clinical practice may aid in providing appropriate treatment strategies, ultimately leading to favorable patient outcomes,” the authors concluded.
