title: FDG-PET/CT findings in systemic mastocytosis: a French multicentre study.
abstract: BACKGROUND
  Mastocytosis is a clonal haematological disease characterized by uncontrolled proliferation and the activation of mast cells. The value of FDG-PET/CT (FDG-PET) in mastocytosis has yet to be determined.
  
  
  METHODS
  We retrospectively identified patients with an established diagnosis of systemic mastocytosis (SM), according to the WHO criteria, who underwent PET using the French Reference Centre for Mastocytosis database. Semi-quantitative and visual analysis of FDG-PET was performed and compared to the clinico-biological data.
  
  
  RESULTS
  Our cohort included 19 adult patients, median age 65 years [range 58-74], including three with smouldering SM (SSM), three with aggressive SM (ASM), 10 with an associated clonal haematological non-mast-cell lineage disease (SM-AHNMD), and three with mast cell sarcoma (MCS). FDG-PET was performed at the time of the SM diagnosis (15/19), to evaluate lymph node (LN) activity (3/19) or the efficacy of therapy (1/19). FDG uptake was observed in the bone marrow (BM) (9/19, 47%), LN (6/19, 32%), spleen (12/19, 63%), or liver (1/19, 5%). No significant FDG uptake was observed in the SSM and ASM patients. A pathological FDG uptake was observed in the BM of 6/10 patients with SM-AHNMD, appearing as diffuse and homogeneous, and in the LN of 5/10 patients. All 3 MCS patients showed intense and multifocal BM pathological uptake, mimicking metastasis. No correlation was found between the FDG-PET findings and serum tryptase levels, BM mast cell infiltration percentage, and CD30 and CD2 expression by mast cells.
  
  
  CONCLUSIONS
  FDG uptake does not appear to be a sensitive marker of mast cell activation or proliferation because no significant FDG uptake was observed in most common forms of mastocytosis (notably purely aggressive SM). However, pathological FDG uptake was observed in the SM-AHNMD and in MCS cases, suggesting a role of FDG-PET in their early identification and as a tool of therapeutic assessment in this subgroup of patients.
authors.affiliation: Department of Nuclear Medicine, Avicenne Hospital, Assistance Publique - Hôpitaux de Paris (APHP), Bobigny, France.|Sorbonne Paris Cité, Paris 13 University, Bobigny, France.
authors.forename: S
authors.initials: S
authors.lastname: Djelbani-Ahmed
authors.affiliation: French Reference center for Mastocytosis (Centre de Référence des Mastocytoses, CEREMAST), Necker Children's Hospital, APHP, Paris, France.|Department of Haematology, Necker Children's Hospital, APHP, Paris, France.|Sorbonne Paris Cité, Imagine Institute, Paris Descartes University, Paris, France.
authors.forename: M O
authors.initials: MO
authors.lastname: Chandesris
authors.affiliation: Department of Internal Medicine and Inflammation-Immunopathology-Biotherapy Department (DHU i2B), AP-HP, Saint Antoine Hospital, Paris, France.
authors.forename: A
authors.initials: A
authors.lastname: Mekinian
authors.affiliation: French Reference center for Mastocytosis (Centre de Référence des Mastocytoses, CEREMAST), Necker Children's Hospital, APHP, Paris, France.|Sorbonne Paris Cité, Imagine Institute, Paris Descartes University, Paris, France.|Department of Pathology, Necker Children's Hospital, APHP, Paris, France.
authors.forename: D
authors.initials: D
authors.lastname: Canioni
authors.affiliation: French Reference center for Mastocytosis (Centre de Référence des Mastocytoses, CEREMAST), Necker Children's Hospital, APHP, Paris, France.|Sorbonne Paris Cité, Imagine Institute, Paris Descartes University, Paris, France.|Laboratory of Haematology, Necker Children's Hospital, APHP, Paris, France.
authors.forename: C
authors.initials: C
authors.lastname: Brouzes
authors.affiliation: French Reference center for Mastocytosis (Centre de Référence des Mastocytoses, CEREMAST), Necker Children's Hospital, APHP, Paris, France.|INSERM U1068, Centre de Recherche en Cancérologie de Marseille (Signaling, Hematopoiesis and Mechanism of Oncogenesis), Paoli Calmettes Institute, Aix-Marseille University, Marseille, France.
authors.forename: K
authors.initials: K
authors.lastname: Hanssens
authors.affiliation: Department of Nuclear Medicine, Avicenne Hospital, Assistance Publique - Hôpitaux de Paris (APHP), Bobigny, France.
authors.forename: G
authors.initials: G
authors.lastname: Pop
authors.affiliation: Department of Internal and Vascular Medicine, Hospices Civils de Lyon, Groupe Hopitalier Sud, Université de Lyon, Pierre-Bénite, France.
authors.forename: I
authors.initials: I
authors.lastname: Durieu
authors.affiliation: Department of Internal and Vascular Medicine, Hospices Civils de Lyon, Groupe Hopitalier Sud, Université de Lyon, Pierre-Bénite, France.
authors.forename: S
authors.initials: S
authors.lastname: Durupt
authors.affiliation: Department of Internal Medicine, Rennes University Hospital, Rennes, France.
authors.forename: B
authors.initials: B
authors.lastname: Grosbois
authors.affiliation: Department of Internal Medicine, Rennes University Hospital, Rennes, France.
authors.forename: S
authors.initials: S
authors.lastname: Besnard
authors.affiliation: Department of Internal Medicine, Clermont-Ferrand University Hospital, Clermont-Ferrand, France.
authors.forename: O
authors.initials: O
authors.lastname: Tournilhac
authors.affiliation: Department of Internal Medicine, Purpan University Hospital, Toulouse, France.
authors.forename: O
authors.initials: O
authors.lastname: Beyne-Rauzy
authors.affiliation: Department of Oncology and Haematology, Saint-Denis University Hospital, Saint-Denis de la Réunion, France.
authors.forename: P
authors.initials: P
authors.lastname: Agapé
authors.affiliation: Department of Haematology, Reims University Hospital, Reims, France.
authors.forename: A
authors.initials: A
authors.lastname: Delmer
authors.affiliation: Department of Haematology, Brabois University Hospital, Vandoeuvre les Nancy, France.
authors.forename: D
authors.initials: D
authors.lastname: Ranta
authors.affiliation: Department of Internal Medicine, Nice University Hospital, Nice, France.
authors.forename: P Y
authors.initials: PY
authors.lastname: Jeandel
authors.affiliation: Department of Internal Medicine, Tenon Hospital, Paris, France.
authors.forename: S
authors.initials: S
authors.lastname: Georgin-Lavialle
authors.affiliation: French Reference center for Mastocytosis (Centre de Référence des Mastocytoses, CEREMAST), Necker Children's Hospital, APHP, Paris, France.|Department of Haematology, Necker Children's Hospital, APHP, Paris, France.|Sorbonne Paris Cité, Imagine Institute, Paris Descartes University, Paris, France.
authors.forename: L
authors.initials: L
authors.lastname: Frenzel
authors.affiliation: French Reference center for Mastocytosis (Centre de Référence des Mastocytoses, CEREMAST), Necker Children's Hospital, APHP, Paris, France.|Department of Haematology, Caen University Hospital, Caen, France.
authors.forename: G
authors.initials: G
authors.lastname: Damaj
authors.affiliation: Department of Nuclear Medicine, Avicenne Hospital, Assistance Publique - Hôpitaux de Paris (APHP), Bobigny, France.
authors.forename: V
authors.initials: V
authors.lastname: Eder
authors.affiliation: French Reference center for Mastocytosis (Centre de Référence des Mastocytoses, CEREMAST), Necker Children's Hospital, APHP, Paris, France.|Sorbonne Paris Cité, Imagine Institute, Paris Descartes University, Paris, France.|Department of Infectious Diseases and Tropical Medicine, Necker Children's Hospital, APHP, Pasteur Institute, Paris, France.
authors.forename: O
authors.initials: O
authors.lastname: Lortholary
authors.affiliation: French Reference center for Mastocytosis (Centre de Référence des Mastocytoses, CEREMAST), Necker Children's Hospital, APHP, Paris, France.|Department of Haematology, Necker Children's Hospital, APHP, Paris, France.|Sorbonne Paris Cité, Imagine Institute, Paris Descartes University, Paris, France.
authors.forename: O
authors.initials: O
authors.lastname: Hermine
authors.affiliation: Department of Internal Medicine and Inflammation-Immunopathology-Biotherapy Department (DHU i2B), AP-HP, Saint Antoine Hospital, Paris, France.
authors.forename: O
authors.initials: O
authors.lastname: Fain
authors.affiliation: Department of Nuclear Medicine, Avicenne Hospital, Assistance Publique - Hôpitaux de Paris (APHP), Bobigny, France. michael.soussan@avc.aphp.fr.|Sorbonne Paris Cité, Paris 13 University, Bobigny, France. michael.soussan@avc.aphp.fr.
authors.forename: M
authors.initials: M
authors.lastname: Soussan
mesh_terms: D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18; D005602:France; D006801:Humans; D008297:Male; D034721:Mastocytosis, Systemic / Q000000981:diagnostic imaging*; D008875:Middle Aged; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: FDG PET/CT; Systemic mastocytosis