Contributions
Abstract: PB2305
Type: Publication Only
Background
Mastocytosis is an extremely rare neoplasm originating from abnormal proliferation and tissue infiltration of clonal mast cells. The WHO classification recognizes cutaneous and systemic mastocitosis (SM), the former localized to skin and the latter further classified as indolent or aggressive, based on organ infiltration. Moreover, SM can be associated to another clonal hematological disease (SM-AHD), typically myelodysplastic syndromes (MDS) or acute myeloid leukemia (AML): in these cases the prognosis is similar to the predominant neoplasm.
Aims
The aim of the study is to analyze the characteristics of patients with both indolent and aggressive systemic mastocytosis (SM) and the triggering factors for treatment. We also reviewed the clinical course and treatment of patients with SM-AHD.
Methods
We retrospectively reviewed the charts and collected clinical and laboratory data of 20 patients diagnosed with SM and 9 patients diagnosed with SM-AHD from January 2008 through December 2017. We focused on onset symptoms, clinical characteristics, organ damage and indication to treatment.
Results
SM: Eighteen patients (90%) sought medical evaluation because of cutaneous lesions or anaphylaxis, and 2 (10%) because of bone pain or fractures. In 12 patients (60%) SM was diagnosed after a skin and bone marrow biopsy revealed mast cell infiltration. Six patients (30%) presented with anaphylaxis and high triptase levels: as reported in literature, both characteristics are strongly associated with SM, and both underwent a bone marrow examination. While bone marrow biopsy was always positive for mast cell infiltration, CKIT D816V mutation was detected in 12 patients only. Skeleton X-ray and 18F-FDG PET/CT were performed in 16 patients: 9 (56%) presented a radiological bone involvement but only 4 of them (25%) showed increased glucose uptake. Ten patients were diagnosed with indolent SM, and did not need systemic treatment: they were given antihistamines to control symptoms. Ten patients were diagnosed with aggressive SM: 3 started tirosin kinase inhibitors (TKI) for uncontrolled degranulation causing anaphylaxis and flushing; 5 started Interferon α (IFNα) considering bone pain due to fractures or severe osteoporosis; 2 started cladribine for diffuse bone and systemic involvement. Four patients needed further therapy for transient benefit or primarily poor control of clinical conditions. Of these 20 patients, 18 are surviving at 0.5-89.5 months. SM-AHD: These patients were all diagnosed after performing bone marrow evaluation for cytopenia. Two patients were diagnosed with AML: considering age >65 y.o., they were both treated with intermediate dose citarabine associated to TKI, and died after a median of 3 months. The other 7 patients were diagnosed with MDS: 3 had skin lesion and few symptoms related to uncontrolled degranulation, none presented with bone pain or skeleton alteration at X-ray. Regarding treatment, 2 patients were treated with TKI and 1 with IFNα for underlying SM, and 4 patients with best supportive care for low risk MDS; median overall survival was 23.9 months.
Conclusion
SM is difficult to recognize because it presents with generic symptoms, as anaphylaxis, osteoporosis and fractures, or flushing and gastritis. Nonetheless, it is important to investigate unexplained bone fragility, wasp venom anaphylaxis or non-catecholamine associated flushing, possibly suggesting an underlying mastocytosis. SM-AHD are mainly treated for the predominant non-mast cell disease, associated with antihistamines for symptoms control in few cases.
Session topic: 16. Myeloproliferative neoplasms - Clinical
Keyword(s): Interferon alpha, Kinase Inhibitor, Mast cell disease
Abstract: PB2305
Type: Publication Only
Background
Mastocytosis is an extremely rare neoplasm originating from abnormal proliferation and tissue infiltration of clonal mast cells. The WHO classification recognizes cutaneous and systemic mastocitosis (SM), the former localized to skin and the latter further classified as indolent or aggressive, based on organ infiltration. Moreover, SM can be associated to another clonal hematological disease (SM-AHD), typically myelodysplastic syndromes (MDS) or acute myeloid leukemia (AML): in these cases the prognosis is similar to the predominant neoplasm.
Aims
The aim of the study is to analyze the characteristics of patients with both indolent and aggressive systemic mastocytosis (SM) and the triggering factors for treatment. We also reviewed the clinical course and treatment of patients with SM-AHD.
Methods
We retrospectively reviewed the charts and collected clinical and laboratory data of 20 patients diagnosed with SM and 9 patients diagnosed with SM-AHD from January 2008 through December 2017. We focused on onset symptoms, clinical characteristics, organ damage and indication to treatment.
Results
SM: Eighteen patients (90%) sought medical evaluation because of cutaneous lesions or anaphylaxis, and 2 (10%) because of bone pain or fractures. In 12 patients (60%) SM was diagnosed after a skin and bone marrow biopsy revealed mast cell infiltration. Six patients (30%) presented with anaphylaxis and high triptase levels: as reported in literature, both characteristics are strongly associated with SM, and both underwent a bone marrow examination. While bone marrow biopsy was always positive for mast cell infiltration, CKIT D816V mutation was detected in 12 patients only. Skeleton X-ray and 18F-FDG PET/CT were performed in 16 patients: 9 (56%) presented a radiological bone involvement but only 4 of them (25%) showed increased glucose uptake. Ten patients were diagnosed with indolent SM, and did not need systemic treatment: they were given antihistamines to control symptoms. Ten patients were diagnosed with aggressive SM: 3 started tirosin kinase inhibitors (TKI) for uncontrolled degranulation causing anaphylaxis and flushing; 5 started Interferon α (IFNα) considering bone pain due to fractures or severe osteoporosis; 2 started cladribine for diffuse bone and systemic involvement. Four patients needed further therapy for transient benefit or primarily poor control of clinical conditions. Of these 20 patients, 18 are surviving at 0.5-89.5 months. SM-AHD: These patients were all diagnosed after performing bone marrow evaluation for cytopenia. Two patients were diagnosed with AML: considering age >65 y.o., they were both treated with intermediate dose citarabine associated to TKI, and died after a median of 3 months. The other 7 patients were diagnosed with MDS: 3 had skin lesion and few symptoms related to uncontrolled degranulation, none presented with bone pain or skeleton alteration at X-ray. Regarding treatment, 2 patients were treated with TKI and 1 with IFNα for underlying SM, and 4 patients with best supportive care for low risk MDS; median overall survival was 23.9 months.
Conclusion
SM is difficult to recognize because it presents with generic symptoms, as anaphylaxis, osteoporosis and fractures, or flushing and gastritis. Nonetheless, it is important to investigate unexplained bone fragility, wasp venom anaphylaxis or non-catecholamine associated flushing, possibly suggesting an underlying mastocytosis. SM-AHD are mainly treated for the predominant non-mast cell disease, associated with antihistamines for symptoms control in few cases.
Session topic: 16. Myeloproliferative neoplasms - Clinical
Keyword(s): Interferon alpha, Kinase Inhibitor, Mast cell disease