Cytoreductive therapy
In cases of advanced systemic mastocytosis or rare cases with indolent systemic mastocytosis with very troublesome symptoms, cytoreductive therapy can be indicated. ɑ-interferon. Given as subcutaneous injections. Side effects include fatigue and influenza-like symptoms
Cladribine (CdA). Chemotherapy which is given as subcutaneous injections. Side effects include immunodeficiency and infections. Tyrosine kinase inhibitors (TKI)
Midostaurin. TKI acting on many different tyrosine kinases, approved by FDA and EMA for advanced mastocytosis
Imatinib. Can have effect in rare cases without mutation in KIT(D816V)
Masitinib. Is being tested in trials. Not approved. Midostaurin - 60% respond. Avapritinib in trials; currently being tested but showing promise in reduction of tryptase levels.Allogeneic stem cell transplantation has been used in rare cases with aggressive systemic mastocytosis in patients deemed to be fit for the procedure. Other
Treatment with ultraviolet light can relieve skin symptoms, but may increase the risk of skin cancer. Prognosis
Patients with indolent systemic mastocytosis have a normal life expectancy. The prognosis for patients with advanced systemic mastocytosis differs depending on type of disease with MCL being the most serious form with short survival. Epidemiology
The true incidence and prevalence of mastocytosis is unknown, but mastocytosis generally has been considered to be an "orphan disease"; orphan diseases affect 200,000 or fewer people in the United States. Mastocytosis, however, often may be misdiagnosed, as it typically occurs secondary to another condition, and thus may occur more frequently than assumed.
This should be considered if patients develop any systemic symptoms
Generalized eruption of cutaneous mastocytosis (adult type) is the most common pattern of mastocytosis presenting to the dermatologist, with the most common lesions being macules, papules, or nodules that are disseminated over most of the body but especially on the upper arms, legs, and trunk
Diffuse cutaneous mastocytosis has diffuse involvement in which the entire integument may be thickened and infiltrated with mast cells to produce a peculiar orange color, giving rise to the term "homme orange. "Cutaneous mastocytosis in children usually presents in the first year after birth and in most cases vanishes during adolescence. Systemic mastocytosis (SM)
Systemic mastocytosis involves the bone marrow in the majority of cases and in some cases other internal organs, usually in addition to involving the skin. Mast cells collect in various tissues and can affect organs where mast cells do not normally inhabit such as the liver, spleen and lymph nodes, and organs which have normal populations but where numbers are increased. In the bowel, it may manifest as mastocytic enterocolitis. However, normal ranges for mast cell counts in the gastrointestinal tract mucosa are not well established in the literature, and depend upon the exact location (e.g. right versus left colon), gender, and patient populations (such as asymptomatic patients versus patients with chronic diarrhea of unknown etiology). Quantitative mast cell stains may yield little diagnostic information, and further research studies are warranted to determine whether "mastocytic enterocolitis" truly represents a distinct entity.There are five types of systemic mastocytosis:
Indolent systemic mastocytosis (ISM).