title: Inability of immunomorphometric assessment of angiogenesis to distinguish primary versus secondary myelofibrosis.
abstract: OBJECTIVE
  To explore the utility of bone marrow (BM) angiogenesis in differentiating primary myelofibrosis (PMF) from secondary myelofibrosis (MF).
  
  
  METHODS
  CD34 immunostaining was performed on BM biopsies from 21 PMFs, 23 non-PMF myeloproliferative neoplasms (MPN) with associated MF, 20 secondary MF samples, and 10 nonfibrotic controls. Microvessel density (MVD) and microvessel surface area (MSA), along with blood and BM findings were compared between the groups.
  
  
  RESULTS
  The post-MPN MF cases included chronic myeloid leukemia-MF and polycythemia vera-MF. Etiologies of secondary MF were metastatic carcinomas, non-MPN hematologic malignancies, tuberculosis, autoimmune MF, and osteopetrosis. Megakaryocytic clustering was the most frequent and intrasinusoidal hematopoiesis the most specific feature of PMF. Higher reticulin grade, collagenization, and osteomyelosclerosis were commoner in PMF. MVD and MSA were significantly increased in fibrotic marrows regardless of etiology. Although mean MVD as well as MSA were highest in PMF, extensive overlaps among groups and marked heterogeneity in the secondary MF group rendered them of limited utility in the differential diagnosis.
  
  
  CONCLUSIONS
  Enhanced angiogenesis is not entirely specific for PMF. Overlaps with secondary MF limits its differential diagnostic utility. Pathogenetically, our findings suggest that enhanced angiogenesis is a secondary paraneoplastic stromal response shared by various unrelated conditions.
authors: Department of Hematology, All India Institute of Medical Sciences, New Delhi, India.
authors: Prashant
authors: P
authors: Sharma
authors: Hara Prasad
authors: HP
authors: Pati
authors: Pravas Chandra
authors: PC
authors: Mishra
authors: Amit Kumar
authors: AK
authors: Dinda
authors: Ruchika
authors: R
authors: Gupta
authors: Alok
authors: A
authors: Sharma
authors: Tony George
authors: TG
authors: Jacob
mesh_terms: D001853:Bone Marrow / Q000098:blood supply / Q000473:pathology; D003937:Diagnosis, Differential; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D055806:Microvessels / Q000473:pathology; D009196:Myeloproliferative Disorders / Q000175:diagnosis / Q000209:etiology / Q000473:pathology*; D009389:Neovascularization, Pathologic; D055728:Primary Myelofibrosis / Q000175:diagnosis / Q000473:pathology