title: Janus kinase (JAK) 2 V617F mutation as the cause of primary thrombocythemia in acromegaly with severe visceromegaly and divergence between growth hormone and insulin-like growth factor-1 concentrations during the follow-up: causal or casual association?
abstract: OBJECTIVE
  An increased prevalence of hematological abnormalities is reported in acromegaly, but to date no reports about the presence of the Janus Kinase (JAK) 2 mutation in acromegalic patients have been described.
  
  
  METHODS
  We report the complex clinical presentation of the unique case, never described, of acromegaly due to GH-secreting pituitary adenoma associated with JAK2 V617F mutation.
  
  
  RESULTS
  The patient shows primary thrombocythemia and myelofibrosis, due to JAK2 V617F mutation, severe visceromegaly and a peculiar clinical course of the disease characterized by discrepant values of GH and IGF-1 during somatostatin analog (SA) treatment despite a significant reduction in pituitary adenoma size and therapeutic resistance both to SA and pegvisomant.
  
  
  CONCLUSIONS
  The presence of JAK2 V617F mutation is a cause of primary thrombocythemia and myelofibrosis in acromegaly. In this patient, a peculiar clinical course of acromegaly was observed, with the difficulty in controlling the disease. More data, on a larger cohort of patients, could clarify whether JAK2 V617F mutation has a serious impact on the clinical features and course of acromegaly.
authors.affiliation: Section of Endocrinology, Laboratory of Molecular Endocrinology, Biomedical Department of Internal and Specialist Medicine-DIBIMIS, University of Palermo, Palermo, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Ciresi
authors.forename: Valentina
authors.initials: V
authors.lastname: Guarnotta
authors.forename: Laura
authors.initials: L
authors.lastname: Tomasello
authors.forename: Valentina
authors.initials: V
authors.lastname: Calò
authors.forename: Antonio
authors.initials: A
authors.lastname: Russo
authors.forename: Aldo
authors.initials: A
authors.lastname: Galluzzo
authors.forename: Carla
authors.initials: C
authors.lastname: Giordano
mesh_terms: D000172:Acromegaly / Q000235:genetics* / Q000378:metabolism; D000368:Aged; D000818:Animals; D015331:Cohort Studies; D005500:Follow-Up Studies; D019382:Human Growth Hormone / Q000378:metabolism; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D053614:Janus Kinase 2 / Q000235:genetics*; D008297:Male; D009154:Mutation; D010911:Pituitary Neoplasms / Q000378:metabolism; D010976:Platelet Count; D011874:Radiometry / Q000379:methods; D013920:Thrombocythemia, Essential / Q000235:genetics*; D013997:Time Factors
chemical_list: D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; C507924:JAK2 protein, human; D053614:Janus Kinase 2