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{{Mast cell tumor}}
{{Mast cell tumor}}
{{CMG}};{{AE}}{{PSK}}
==Overview==
==Overview==
Mast cell tumor is a rare and heterogeneous disease characterized by the presence of excessive numbers of [[mast cells]] in various organs, mainly the [[skin]] and the [[bone marrow]] that manifests with an unusually broad spectrum of clinical and morphological appearances. Based on the affected organ(s), mast cell tumor may be classified into either cutaneous mastocytosis or systemic mastocytosis. Mast cell tumor may be classified into seven subtypes based on [[WHO]] classification system.<ref name="pmid17488167">{{cite journal| author=Patnaik MM, Rindos M, Kouides PA, Tefferi A, Pardanani A| title=Systemic mastocytosis: a concise clinical and laboratory review. | journal=Arch Pathol Lab Med | year= 2007 | volume= 131 | issue= 5 | pages= 784-91 | pmid=17488167 | doi=10.1043/1543-2165(2007)131[784:SMACCA]2.0.CO;2 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=17488167  }} </ref> Cutaneous mastocytosis is more common in children and the disease manifest itself in the first year of life in over 80% of cases.<ref name="FerranteScavone2015">{{cite journal|last1=Ferrante|first1=Giuliana|last2=Scavone|first2=Valeria|last3=Muscia|first3=Maria|last4=Adrignola|first4=Emilia|last5=Corsello|first5=Giovanni|last6=Passalacqua|first6=Giovanni|last7=La Grutta|first7=Stefania|title=The care pathway for children with urticaria, angioedema, mastocytosis|journal=World Allergy Organization Journal|volume=8|issue=1|year=2015|pages=5|issn=1939-4551|doi=10.1186/s40413-014-0052-x}}</ref> There is no sex predilection and race predilection to the mast cell tumor.  Mast cell tumor arises from the [[mast cell]], which is a type of [[white blood cell]] involved in the inflammatory process. The progression to mast cell tumor usually involves the uncontrolled stimulation of the [[receptor]] for [[stem cell factor]] following mutation of [[C-kit]] cell surface receptor.<ref name="AdolfMillonig2012">{{cite journal|last1=Adolf|first1=Stefanie|last2=Millonig|first2=Gunda|last3=Seitz|first3=Helmut Karl|last4=Reiter|first4=Andreas|last5=Schirmacher|first5=Peter|last6=Longerich|first6=Thomas|last7=Mueller|first7=Sebastian|title=Systemic Mastocytosis: A Rare Case of Increased Liver Stiffness|journal=Case Reports in Hepatology|volume=2012|year=2012|pages=1–6|issn=2090-6587|doi=10.1155/2012/728172}}</ref> On microscopic histopathological analysis, mast cells in the superficial and mid dermis that are lymphocyte like with dense granular cytoplasm which tend to be more abundant around blood vessels is characteristic finding of mast cell tumor.<ref name=LP>Mastocytosis. Libre Pathology. http://librepathology.org/wiki/Mastocytosis accessed on March 1st, 2016</ref> Mast cell tumor must be differentiated from other diseases that cause [[flushing]],such as: [[phaeochromocytoma]] and [[carcinoid syndrome]].<ref name=Patient>Mastocytosis and mast cell disorders.Patient info.http://patient.info/doctor/mastocytosis-and-mast-cell-disorders#ref-20 accessed on March 7th, 2016</ref> Mast cell tumor must be differentiated from other diseases that cause elevated serum tryptase levels and cytopenia, such as: [[myelodysplastic syndrome]], [[primary myelofibrosis]], [[essential thrombocythemia]], and [[chronic eosinophilic leukemia]].
Mast cell tumor is a rare and heterogeneous disease characterized by the presence of excessive numbers of [[mast cells]] in various organs, mainly the [[skin]] and the [[bone marrow]] that manifests with an unusually broad spectrum of clinical and morphological appearances. Based on the affected organ(s), mast cell tumor may be classified into either cutaneous mastocytosis or systemic mastocytosis. Mast cell tumor may be classified into seven subtypes based on [[WHO]] classification system. Cutaneous mastocytosis is more common in children and the disease manifest itself in the first year of life in over 80% of cases. There is no sex predilection and race predilection to the mast cell tumor.  Mast cell tumor arises from the [[mast cell]], which is a type of [[white blood cell]] involved in the inflammatory process. The progression to mast cell tumor usually involves the uncontrolled stimulation of the [[receptor]] for [[stem cell factor]] following mutation of [[C-kit]] cell surface receptor. On microscopic histopathological analysis, mast cells in the superficial and mid dermis that are lymphocyte like with dense granular cytoplasm which tend to be more abundant around blood vessels is characteristic finding of mast cell tumor. Mast cell tumor must be differentiated from other diseases that cause [[flushing]],such as: [[phaeochromocytoma]] and [[carcinoid syndrome]]. Mast cell tumor must be differentiated from other diseases that cause elevated serum tryptase levels and cytopenia, such as: [[myelodysplastic syndrome]], [[primary myelofibrosis]], [[essential thrombocythemia]], and [[chronic eosinophilic leukemia]]. Common complications of mast cell tumor include episodes of [[anaphylaxis]], [[osteoporosis]], and progression to [[malignant]] mastocytosis or [[mast cell leukemia]]. The [[prognosis]] of mast cell tumor varies with the subtype, location, and extent of the tumor. The cutaneous mastocytosis is associated with the most favorable prognosis and mast cell [[leukemia]] is associated with poor prognosis. The diagnosis of systemic mastocytosis is based on the presence of one major criterion and one minor criterion or three minor criteria. Major criteria include the presence of multifocal dense infiltrates of [[mast cells]] observed in [[bone marrow]] sections or other extra [[cutaneous]] organs. Four minor criteria include the presence of >25% abnormal spindle-shaped mast cells in bone marrow and/or tissues, detection of Kit mutation at codon 816 in bone marrow or extracutaneous organ(s), the expression of CD2 and
CD25 surface markers in [[C-kit]] positive [[mast cells]] from [[bone marrow]] or other organs, and elevated serum [[tryptase]] levels >20 ng/mL. Physical examination for mast cell tumor include inspection for a large assortment of types of skin lesions, testing for [[dermatographism]] (Darier's sign), and palpating for [[hepatosplenomegaly]] and [[lymphadenopathy]]. Laboratory tests that may be helpful for diagnosis of mast cell tumor include [[complete blood count]], serum [[tryptase]] levels, plasma and urinary [[histamine]] levels, and coagulation profile. [[Biopsy]] of affected organ may be performed to detect possible accumulation of [[mast cells]] in an involved tissue. Other imaging studies for evaluation of mast cell tumor include [[sonography]] of internal organs, [[gastroscopy]] and [[colonoscopy]] with [[biopsy]], and [[DXA]] scan of bones. The mainstay of therapy for mast cell tumor is avoidance of triggering factors and symptomatic therapy. Chemotherapy is indicated for aggressive form of mast cell tumor.


==Historical Perspective==
Mast cell activation was first described by Dr. Nettleship and Tay in 1869. Dr. Sezary and other french scientists reported the first case of mast cell tumor in 1936.
==Classification==
==Classification==
Based on the affected organ(s), mast cell tumor may be classified into either cutaneous mastocytosis or systemic mastocytosis. Mast cell tumor may be classified into seven subtypes based on [[WHO]] classification system.<ref name="pmid17488167">{{cite journal| author=Patnaik MM, Rindos M, Kouides PA, Tefferi A, Pardanani A| title=Systemic mastocytosis: a concise clinical and laboratory review. | journal=Arch Pathol Lab Med | year= 2007 | volume= 131 | issue= 5 | pages= 784-91 | pmid=17488167 | doi=10.1043/1543-2165(2007)131[784:SMACCA]2.0.CO;2 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=17488167  }} </ref>
Based on the affected organ(s), mast cell tumor may be classified into either cutaneous mastocytosis or systemic mastocytosis. Mast cell tumor may be classified into seven subtypes based on [[WHO]] classification system.
==Pathophysiology==
==Pathophysiology==
Mast cell tumor arises from the mast cell, which is a type of white blood cell involved in the inflammatory process. The progression to mast cell tumor usually involves the uncontrolled stimulation of the [[receptor]] for [[stem cell factor]] following mutation of [[C-kit]] cell surface receptor.<ref name="AdolfMillonig2012">{{cite journal|last1=Adolf|first1=Stefanie|last2=Millonig|first2=Gunda|last3=Seitz|first3=Helmut Karl|last4=Reiter|first4=Andreas|last5=Schirmacher|first5=Peter|last6=Longerich|first6=Thomas|last7=Mueller|first7=Sebastian|title=Systemic Mastocytosis: A Rare Case of Increased Liver Stiffness|journal=Case Reports in Hepatology|volume=2012|year=2012|pages=1–6|issn=2090-6587|doi=10.1155/2012/728172}}</ref> On microscopic histopathological analysis, mast cells in the superficial and mid dermis that are lymphocyte like with dense granular cytoplasm which tend to be more abundant around blood vessels is characteristic finding of mast cell tumor.<ref name=LP>Mastocytosis. Libre Pathology. http://librepathology.org/wiki/Mastocytosis accessed on March 1st, 2016</ref>
Mast cell tumor arises from the mast cell, which is a type of white blood cell involved in the inflammatory process. The progression to mast cell tumor usually involves the uncontrolled stimulation of the [[receptor]] for [[stem cell factor]] following mutation of [[C-kit]] cell surface receptor. On microscopic histopathological analysis, mast cells in the superficial and mid dermis that are lymphocyte like with dense granular cytoplasm which tend to be more abundant around blood vessels is characteristic finding of mast cell tumor.
==Causes==
==Causes==
There are no established causes for mast cell tumor.
There are no established causes for mast cell tumor.
==Differentiating Mast Cell Tumor from other Diseases==
==Differentiating Mast Cell Tumor from other Diseases==
Mast cell tumor must be differentiated from other diseases that cause [[flushing]],such as: [[phaeochromocytoma]] and [[carcinoid syndrome]].<ref name=Patient>Mastocytosis and mast cell disorders.Patient info.http://patient.info/doctor/mastocytosis-and-mast-cell-disorders#ref-20 accessed on March 7th, 2016</ref> Mast cell tumor must be differentiated from other diseases that cause elevated serum tryptase levels and cytopenia, such as: [[myelodysplastic syndrome]], [[primary myelofibrosis]], [[essential thrombocythemia]], and [[chronic eosinophilic leukemia]].
Mast cell tumor must be differentiated from other diseases that cause [[flushing]],such as: [[phaeochromocytoma]] and [[carcinoid syndrome]]. Mast cell tumor must be differentiated from other diseases that cause elevated serum tryptase levels and cytopenia, such as: [[myelodysplastic syndrome]], [[primary myelofibrosis]], [[essential thrombocythemia]], and [[chronic eosinophilic leukemia]].
==Epidemiology and Demographics==
==Epidemiology and Demographics==
Mast cell tumor is a rare disease and considered to be an "orphan disease" affecting 200,000 or fewer people in the United States. There are no definite data regarding the prevalence of mast cell tumor among the US general population.<ref name="KoenigMorel2008">{{cite journal|last1=Koenig|first1=Martial|last2=Morel|first2=Jérôme|last3=Reynaud|first3=Jacqueline|last4=Varvat|first4=Cécile|last5=Cathébras|first5=Pascal|title=An unusual cause of spontaneous bleeding in the intensive care unit – mastocytosis: a case report|journal=Cases Journal|volume=1|issue=1|year=2008|pages=100|issn=1757-1626|doi=10.1186/1757-1626-1-100}}</ref> Cutaneous mastocytosis is more common in children and the disease manifest itself in the first year of life in over 80% of cases.<ref name="FerranteScavone2015">{{cite journal|last1=Ferrante|first1=Giuliana|last2=Scavone|first2=Valeria|last3=Muscia|first3=Maria|last4=Adrignola|first4=Emilia|last5=Corsello|first5=Giovanni|last6=Passalacqua|first6=Giovanni|last7=La Grutta|first7=Stefania|title=The care pathway for children with urticaria, angioedema, mastocytosis|journal=World Allergy Organization Journal|volume=8|issue=1|year=2015|pages=5|issn=1939-4551|doi=10.1186/s40413-014-0052-x}}</ref> There is no sex predilection and race predilection to the mast cell tumor.
Mast cell tumor is a rare disease and considered to be an "orphan disease" affecting 200,000 or fewer people in the United States. There are no definite data regarding the prevalence of mast cell tumor among the US general population. Cutaneous mastocytosis is more common in children and the disease manifest itself in the first year of life in over 80% of cases. There is no sex predilection and race predilection to the mast cell tumor.
==Risk Factors==
==Risk Factors==
Common risk factors in the development of mast cell tumor are age and mutation of [[C-kit]] receptor.
Common risk factors in the development of mast cell tumor are age and mutation of [[C-kit]] receptor.
==Natural History, Complications and Prognosis==
==Natural History, Complications and Prognosis==
Common complications of mast cell tumor include episodes of [[anaphylaxis]], [[osteoporosis]], and progression to [[malignant]] mastocytosis or [[mast cell leukemia]]. The [[prognosis]] of mast cell tumor varies with the subtype, location, and extent of the tumor. The cutaneous mastocytosis is associated with the most favorable prognosis and mast cell [[leukemia]] is associated with poor prognosis.<ref name=Patient>Mastocytosis and mast cell disorders.Patient info.http://patient.info/doctor/mastocytosis-and-mast-cell-disorders#ref-20 accessed on March 7th, 2016</ref>
Common complications of mast cell tumor include episodes of [[anaphylaxis]], [[osteoporosis]], and progression to [[malignant]] mastocytosis or [[mast cell leukemia]]. The [[prognosis]] of mast cell tumor varies with the subtype, location, and extent of the tumor. The cutaneous mastocytosis is associated with the most favorable prognosis and mast cell [[leukemia]] is associated with poor prognosis.
==Diagnostic Criteria==
==Diagnostic Criteria==
The diagnosis of systemic mastocytosis is based on the presence of one major criterion and one minor criterion or three minor criteria. Major criteria include the presence of multifocal dense infiltrates of [[mast cells]] observed in [[bone marrow]] sections or other extra [[cutaneous]] organs.<ref name="MolderingsBrettner2011">{{cite journal|last1=Molderings|first1=Gerhard J|last2=Brettner|first2=Stefan|last3=Homann|first3=Jürgen|last4=Afrin|first4=Lawrence B|title=Mast cell activation disease: a concise practical guide for diagnostic workup and therapeutic options|journal=Journal of Hematology & Oncology|volume=4|issue=1|year=2011|pages=10|issn=1756-8722|doi=10.1186/1756-8722-4-10}}</ref> Four minor criteria include the presence of >25% abnormal spindle-shaped mast cells in bone marrow and/or tissues, detection of Kit mutation at codon 816 in bone marrow or extracutaneous organ(s), the expression of CD2 and
The diagnosis of systemic mastocytosis is based on the presence of one major criterion and one minor criterion or three minor criteria. Major criteria include the presence of multifocal dense infiltrates of [[mast cells]] observed in [[bone marrow]] sections or other extra [[cutaneous]] organs. Four minor criteria include the presence of >25% abnormal spindle-shaped mast cells in bone marrow and/or tissues, detection of Kit mutation at codon 816 in bone marrow or extracutaneous organ(s), the expression of CD2 and
CD25 surface markers in [[C-kit]] positive [[mast cells]] from [[bone marrow]] or other organs, and elevated serum [[tryptase]] levels >20 ng/mL.
CD25 surface markers in [[C-kit]] positive [[mast cells]] from [[bone marrow]] or other organs, and elevated serum [[tryptase]] levels >20 ng/mL.
==Diagnosis==
==Diagnosis==
Line 26: Line 30:
===History and Symptoms===
===History and Symptoms===
===Physical Examination===
===Physical Examination===
Physical examination for mast cell tumor include inspection for a large assortment of types of skin lesions, testing for [[dermatographism]] (Darier's sign), and palpating for [[hepatosplenomegaly]] and [[lymphadenopathy]].<ref name="MolderingsBrettner2011">{{cite journal|last1=Molderings|first1=Gerhard J|last2=Brettner|first2=Stefan|last3=Homann|first3=Jürgen|last4=Afrin|first4=Lawrence B|title=Mast cell activation disease: a concise practical guide for diagnostic workup and therapeutic options|journal=Journal of Hematology & Oncology|volume=4|issue=1|year=2011|pages=10|issn=1756-8722|doi=10.1186/1756-8722-4-10}}</ref>
Physical examination for mast cell tumor include inspection for a large assortment of types of skin lesions, testing for [[dermatographism]] (Darier's sign), and palpating for [[hepatosplenomegaly]] and [[lymphadenopathy]].
===Laboratory Findings===
===Laboratory Findings===
Laboratory tests for mast cell tumor that may be helpful in diagnosis include [[complete blood count]], serum [[tryptase]] levels, plasma and urinary [[histamine]] levels, and coagulation profile.
Laboratory tests that may be helpful for diagnosis of mast cell tumor include [[complete blood count]], serum [[tryptase]] levels, plasma and urinary [[histamine]] levels, and coagulation profile.
 
===Biopsy===
===Biopsy===
[[Biopsy]] of affected organ may be performed to detect possible accumulation of [[mast cells]] in an involved tissue.
[[Biopsy]] of affected organ may be performed to detect possible accumulation of [[mast cells]] in an involved tissue.
===Other Imaging Findings===
===Other Imaging Findings===
Other imaging studies for mast cell tumor include [[sonography]] of internal organs, [[gastroscopy]] and [[colonoscopy]] with [[biopsy]], and [[DXA]] scan of bones.<ref name="MolderingsBrettner2011">{{cite journal|last1=Molderings|first1=Gerhard J|last2=Brettner|first2=Stefan|last3=Homann|first3=Jürgen|last4=Afrin|first4=Lawrence B|title=Mast cell activation disease: a concise practical guide for diagnostic workup and therapeutic options|journal=Journal of Hematology & Oncology|volume=4|issue=1|year=2011|pages=10|issn=1756-8722|doi=10.1186/1756-8722-4-10}}</ref>
Other imaging studies for evaluation of mast cell tumor include [[sonography]] of internal organs, [[gastroscopy]] and [[colonoscopy]] with [[biopsy]], and [[DXA]] scan of bones.
 
==Treatment==
==Treatment==
===Medical Therapy===
===Medical Therapy===
The mainstay of therapy for mast cell tumor is avoidance of triggering factors and symptomatic therapy.<ref name="KoenigMorel2008">{{cite journal|last1=Koenig|first1=Martial|last2=Morel|first2=Jérôme|last3=Reynaud|first3=Jacqueline|last4=Varvat|first4=Cécile|last5=Cathébras|first5=Pascal|title=An unusual cause of spontaneous bleeding in the intensive care unit – mastocytosis: a case report|journal=Cases Journal|volume=1|issue=1|year=2008|pages=100|issn=1757-1626|doi=10.1186/1757-1626-1-100}}</ref> Chemotherapy is indicated for aggressive form of mast cell tumor.
The mainstay of therapy for mast cell tumor is avoidance of triggering factors and symptomatic therapy. Chemotherapy is indicated for aggressive form of mast cell tumor.
===Surgery===
===Surgery===
Surgical intervention is not recommended for the management of mast cell tumor.
Surgical intervention is not recommended for the management of mast cell tumor.
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[[Category:Types of cancer]]
[[Category:Types of cancer]]
[[Category:Pathology]]
[[Category:Pathology]]
[[Category:Up-To-Date]]
[[Category:Oncology]]
[[Category:Medicine]]
[[Category:Hematology]]
[[Category:Immunology]]

Latest revision as of 15:47, 14 May 2019

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1];Associate Editor(s)-in-Chief: Suveenkrishna Pothuru, M.B,B.S. [2]

Overview

Mast cell tumor is a rare and heterogeneous disease characterized by the presence of excessive numbers of mast cells in various organs, mainly the skin and the bone marrow that manifests with an unusually broad spectrum of clinical and morphological appearances. Based on the affected organ(s), mast cell tumor may be classified into either cutaneous mastocytosis or systemic mastocytosis. Mast cell tumor may be classified into seven subtypes based on WHO classification system. Cutaneous mastocytosis is more common in children and the disease manifest itself in the first year of life in over 80% of cases. There is no sex predilection and race predilection to the mast cell tumor. Mast cell tumor arises from the mast cell, which is a type of white blood cell involved in the inflammatory process. The progression to mast cell tumor usually involves the uncontrolled stimulation of the receptor for stem cell factor following mutation of C-kit cell surface receptor. On microscopic histopathological analysis, mast cells in the superficial and mid dermis that are lymphocyte like with dense granular cytoplasm which tend to be more abundant around blood vessels is characteristic finding of mast cell tumor. Mast cell tumor must be differentiated from other diseases that cause flushing,such as: phaeochromocytoma and carcinoid syndrome. Mast cell tumor must be differentiated from other diseases that cause elevated serum tryptase levels and cytopenia, such as: myelodysplastic syndrome, primary myelofibrosis, essential thrombocythemia, and chronic eosinophilic leukemia. Common complications of mast cell tumor include episodes of anaphylaxis, osteoporosis, and progression to malignant mastocytosis or mast cell leukemia. The prognosis of mast cell tumor varies with the subtype, location, and extent of the tumor. The cutaneous mastocytosis is associated with the most favorable prognosis and mast cell leukemia is associated with poor prognosis. The diagnosis of systemic mastocytosis is based on the presence of one major criterion and one minor criterion or three minor criteria. Major criteria include the presence of multifocal dense infiltrates of mast cells observed in bone marrow sections or other extra cutaneous organs. Four minor criteria include the presence of >25% abnormal spindle-shaped mast cells in bone marrow and/or tissues, detection of Kit mutation at codon 816 in bone marrow or extracutaneous organ(s), the expression of CD2 and CD25 surface markers in C-kit positive mast cells from bone marrow or other organs, and elevated serum tryptase levels >20 ng/mL. Physical examination for mast cell tumor include inspection for a large assortment of types of skin lesions, testing for dermatographism (Darier's sign), and palpating for hepatosplenomegaly and lymphadenopathy. Laboratory tests that may be helpful for diagnosis of mast cell tumor include complete blood count, serum tryptase levels, plasma and urinary histamine levels, and coagulation profile. Biopsy of affected organ may be performed to detect possible accumulation of mast cells in an involved tissue. Other imaging studies for evaluation of mast cell tumor include sonography of internal organs, gastroscopy and colonoscopy with biopsy, and DXA scan of bones. The mainstay of therapy for mast cell tumor is avoidance of triggering factors and symptomatic therapy. Chemotherapy is indicated for aggressive form of mast cell tumor.

Historical Perspective

Mast cell activation was first described by Dr. Nettleship and Tay in 1869. Dr. Sezary and other french scientists reported the first case of mast cell tumor in 1936.

Classification

Based on the affected organ(s), mast cell tumor may be classified into either cutaneous mastocytosis or systemic mastocytosis. Mast cell tumor may be classified into seven subtypes based on WHO classification system.

Pathophysiology

Mast cell tumor arises from the mast cell, which is a type of white blood cell involved in the inflammatory process. The progression to mast cell tumor usually involves the uncontrolled stimulation of the receptor for stem cell factor following mutation of C-kit cell surface receptor. On microscopic histopathological analysis, mast cells in the superficial and mid dermis that are lymphocyte like with dense granular cytoplasm which tend to be more abundant around blood vessels is characteristic finding of mast cell tumor.

Causes

There are no established causes for mast cell tumor.

Differentiating Mast Cell Tumor from other Diseases

Mast cell tumor must be differentiated from other diseases that cause flushing,such as: phaeochromocytoma and carcinoid syndrome. Mast cell tumor must be differentiated from other diseases that cause elevated serum tryptase levels and cytopenia, such as: myelodysplastic syndrome, primary myelofibrosis, essential thrombocythemia, and chronic eosinophilic leukemia.

Epidemiology and Demographics

Mast cell tumor is a rare disease and considered to be an "orphan disease" affecting 200,000 or fewer people in the United States. There are no definite data regarding the prevalence of mast cell tumor among the US general population. Cutaneous mastocytosis is more common in children and the disease manifest itself in the first year of life in over 80% of cases. There is no sex predilection and race predilection to the mast cell tumor.

Risk Factors

Common risk factors in the development of mast cell tumor are age and mutation of C-kit receptor.

Natural History, Complications and Prognosis

Common complications of mast cell tumor include episodes of anaphylaxis, osteoporosis, and progression to malignant mastocytosis or mast cell leukemia. The prognosis of mast cell tumor varies with the subtype, location, and extent of the tumor. The cutaneous mastocytosis is associated with the most favorable prognosis and mast cell leukemia is associated with poor prognosis.

Diagnostic Criteria

The diagnosis of systemic mastocytosis is based on the presence of one major criterion and one minor criterion or three minor criteria. Major criteria include the presence of multifocal dense infiltrates of mast cells observed in bone marrow sections or other extra cutaneous organs. Four minor criteria include the presence of >25% abnormal spindle-shaped mast cells in bone marrow and/or tissues, detection of Kit mutation at codon 816 in bone marrow or extracutaneous organ(s), the expression of CD2 and CD25 surface markers in C-kit positive mast cells from bone marrow or other organs, and elevated serum tryptase levels >20 ng/mL.

Diagnosis

Staging

There is no established system for the staging of mast cell tumor.

History and Symptoms

Physical Examination

Physical examination for mast cell tumor include inspection for a large assortment of types of skin lesions, testing for dermatographism (Darier's sign), and palpating for hepatosplenomegaly and lymphadenopathy.

Laboratory Findings

Laboratory tests that may be helpful for diagnosis of mast cell tumor include complete blood count, serum tryptase levels, plasma and urinary histamine levels, and coagulation profile.

Biopsy

Biopsy of affected organ may be performed to detect possible accumulation of mast cells in an involved tissue.

Other Imaging Findings

Other imaging studies for evaluation of mast cell tumor include sonography of internal organs, gastroscopy and colonoscopy with biopsy, and DXA scan of bones.

Treatment

Medical Therapy

The mainstay of therapy for mast cell tumor is avoidance of triggering factors and symptomatic therapy. Chemotherapy is indicated for aggressive form of mast cell tumor.

Surgery

Surgical intervention is not recommended for the management of mast cell tumor.

References

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