Convegno Interregionale SIE Triveneto V erona, 29 maggio 2008

1. Convegno Interregionale SIE TrivenetoVerona, 29 maggio 2008 Caso clinico Marco Ruggeri UO Ematologia Ospedale San Bortolo, Vicenza

2. Caso clinico: esordio Paziente maschio; anni 61; ipertensione arteriosa in trattamento Dicembre 1989 episodio di vomito e cefalea; PA 222/100 TAC cerebrale: emorragia intraparenchimale Hb: 22.9 g/dL; Ht: 68%; GB: 7.5 x 109/L; Plt:179 x 109/L Ricovero, inizia salasso-terapia

3. Caso clinico: diagnosi Masse eritrocitarie: 3.614, pari a 53.9 cm3/Kg (VN 1.800 ± 250) Saturazione O2 sangue arterioso: 99% Eco addome: nella norma (milza non palpabile) Vitamina B 12: 713 pg/ml (160-970) Fosfatasi alcalina leucocitaria: nella norma Conta piastrinica e leucocitaria: nella norma BOM: cellularità 70%, reticolo esile, iperplasia eritroblastica Studio emostasi (PTT, PT, TT, tempo emorragia, fattore XIII, vWF plasmatico e intrapiastrinico, lisi euglobuline): nella norma TAC cerebrale (+ 7): riassorbimento ematoma; assenza di lesioni vascolari Diagnosi: morbo di Vaquez in fase iniziale (NO PV sec. PVSG) Terapia: salassi; no ASA

4. Caso clinico: follow-up 1989-2001: salasso-terapia periodica (5-6/anno); conta piastrinica e leucocitaria nella norma; milza mai palpabile 2001: TAO per FA; dosaggio EPO: 2 UI/mL (VN 5-10); crescita colonie eritroidi in assenza di EPO WHO 2001: diagnosi PV (↑masse; non cause secondarie; EEC) dal 2004:non più salassi (sideropenia) 2005: JAK2 Exon 14: assenza di mutazione V617F 2007: mutazione JAK2 Exon 12 (547insL+I540-F547dup8) 2008: persistenza di normali valori emocromocitometrici, non splenomegalia, non sintomi vascolari

6. Diagnostic criteria for PV, ET and PMF PVSG: Wasserman L, Blood, 1968 Wasserman L, Br J Haematol, 1971 Berlin M, Semin Hematol, 1975 Murphy S et al, Semin Hematol, 1986. High specificity for clinical trial enrollment WHO 2001: Jaffe ES et al, IARC Press 2001 Apply to the MPD the WHO REAL classification paradigm WHO 2008: Tefferi A et al, Leukemia 2008 JAK2 mutations (V617F; Exon 12 mutations) WHO 2008 “revised” Samuelson et al, Blood 2008 Spivak et l, Blood DOI 2008 Lack of validation from large scale, prospective studies

7. WHO 2008: classification and diagnosis of myeloproliferative neoplasms: diagnostic algorithms Diagnosis: 2 major + 1 minor all 4 major all 3 major + or 1 major + 2 minor

8. -At Vicenza Hematology Department: from 1995 to 2005 50 patients diagnosed having Idiopathic Erythrocytosis (low EPO serum level) -JAK2 V617F: 0/50 -JAK2 Exon 12 mutations: 5/50 (10%) -All patients treated with phlebotomy to maintain hematocrit level below 45% -No patients treated with cytoreductive therapy or ASA

9. Revision of the literature of cohort of patients with Exon 12 mutations • Scott LM, Tong W, Levine RL et al. JAK2 Exon 12 mutations in Polycythemia Vera and Idiopathic Erythrocytosis. N. Engl J Med 2007; 356: 459-68. • Percy MJ, Scott LM, Erber WN, et al. The frequency of JAK2 exon 12 mutations in idiopathic erythrocytosis patients with low serum erythropoietin levels. Haematologica 2007; 92: 1607-13. • Pardanani A, Lasho TL, Finke C, Hanson CA, Tefferi A. Prevalence and clinicopathological correlates of JAK exon 12 mutations in JAK2V617F-negative Polycythemia vera. Leukemia 2007; 21: 1960-3. • Williams DM, Kim AH, Rogers O, Spivak JL, Molitierno AR. Phenotypic variations and new mutations in JAK2 V617F-negative Polycythemia vera, erythrocytosis, and idiopathic myelofibrosis. Exp Hematol 2007; 35: 1641-46. • Martinez-Aviles Luz, Besses C, Larran AA, Cervantes F, Hernandez-Boluda JC, Bellosillo B. JAK2 exon 12 mutations in polycythemia vera or idiopathic erythrocytosis. Haematologica 2007; 92: 1717-8. • Li S, Kralovics R, De Libero G, Theocharides A, Gisslinger H, Skoda RC. Clonal heterogeneity in Polycythemia vera patients with JAK2 exon 12 and JAK2-V617F mutations. Blood 2008; 111: 3863-6. • Pietra D, Li S, Brisci A et al. Somatic mutations of JAK2 exon 12 in patients with JAK2 (V617F) –negative myeloproliferative disorders. Blood 2008; 111: 1686-9.

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13. Characteristics at diagnosis(comparison with Vicenza PV V617F positive cohort)

14. Characteristics at diagnosis(comparison with Vicenza IE V617F negative Exon 12 negative cohort)

15. Clinical characteristics during follow-up (comparison with ECLAP cohort)Marchioli et al, J Clin Oncol 2005

16. Clinical characteristics during follow-up (comparison Vicenza IE V617F negative Exon 12 negative cohort)

17. Bone marrow histology -Polycytemia Vera: erythroid hyperplasia + increase and clustering of enlarged MK (and often hyperplastic granulopoiesis) are the diagnostic hallmark of PV (Georgii at al, Leuk Lyphom, 1996) -21/52 (40%) patients with Exon 12 mutations with bone marrow biopsy at diagnosis: • 14 with erythroid hyperplasia without other abnormalities • 2 with erythroid hyperplasia and mild megakaryocyte atypia • 2 with erythroid and granulocytic hyperplasia • 2 with erythroid and megakaryocytic hyperplasia

18. Frequency of JAK2 mutation in patients with splanchnic vein trombosis(Kiladjian et al, Blood DOI 2008) 241 cases (104 Budd-Chiari Syndrome; 137 Portal Vein Thrombosis JAK2 V617F: 94/241 (39%; 45% BCS; 34% PVT; in 96% of patients with BMB changes specific for MPD + EEC; in 58% of patients with only one of these features; in 7% of those with neither feature) JAK2 Exon 12 mutations: 0/241 (data confirmed by Barosi et al, Blood 2008: 0/93 SVT)

20. Comments Patients with Exon 12 mutations have laboratory, clinical and histo-pathologic characteristics different from patients with PV patients, diagnosed with PVSG criteria, positive for JAK2-V617F mutation Inclusion of these patients in MPD classification as PV appear not appropriate (in particular for the enrollment in RCT) Waiting for large, observational clinical studies, aimed to investigate their natural history, patients with Exon 12 mutations should be classified within the group of IE (e.g Primary Erythrocytosis)