Introduction
Systemic mastocytosis (SM) results from a clonal proliferation of abnormal mast cells (MCs) in extra-cutaneous organs. It could be divided into indolent SM (ISM), smoldering SM (SSM), SM with an associated hematologic (non-MC lineage) neoplasm (SM-AHNMD), aggressive SM (ASM), and mast cell leukemia (MCL). [1-3]
Clinical features of SM could be related to histamine release or to uncontrolled growth and infiltration of clonal MCs in different organs. [2-5] The latter clinical features are divided into B findings (>30% MC infiltration on BM biopsy and serum total tryptase level >200 ng/mL, hepatomegaly with normal liver function, palpable splenomegaly without hypersplenism, and/or lymphadenopathy, signs of dysplasia or myeloproliferation in non-MC lineage, but not diagnostic of an associated hematological neoplasm) or C findings (organ dysfunction due to mast cell infiltration). [2-4] Diagnosis of ISM is established with <2 B findings and no C findings; when > 2 B findings but no C findings are present, the diagnosis is SSM, and when one or more C findings are detected ASM can be diagnosed. [2-4]
The treatment of adult SM should be highly individualized; while the backbone of therapy in ISM and SSM is symptom management, for aggressive and leukemic forms cytoreductive treatment is indicated. [3,4] Historically, cytoreductive agents include interferon-α and cladribine. [3,4,6,7] Allogeneic stem cell transplant could be considered in SM-AHNMD when the associated hematologic neoplasm has an indication to transplantation and in ASM patients with relapsed/refractory disease or in those with acute MCL. [8]
With the advent of the tyrosine kinase inhibitors (TKIs) era, many efforts have been made to find proper inhibitor of SM c-KIT –driver mutation. Midostaurin has been shown to induce major clinical responses with improvement or disappearance of one or more C-findings, a decrease in the MC burden, organomegaly and mediator-related symptoms. [9]
Hereby, we report an extended description of a real-life management of an ASM patient conditioning bulky lymphadenopathy who has undergone to multiple lines of treatment.
All procedures were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2013.