title: Karyotypic and fluorescent in situ hybridization study of the centromere of chromosome 7 in secondary myeloid neoplasms.
abstract: BACKGROUND
  Secondary myeloid neoplasms comprise a group of secondary diseases following exposure to myelotoxic agents or due to congenital diseases. The improvement of anticancer agents and immunosuppressive drugs seem to be associated with an increased incidence of secondary myeloid neoplasms. Karyotyping of bone marrow is essential for diagnosis and prognosis. Previous use of alkylating agents and radiation are associated with clonal abnormalities such as recurrent unbalanced -5/5q-, -7/7q- and complex karyotypes, whereas topoisomerase-II inhibitors lead to changes such as the balanced 11q23 rearrangement, t(8;21), t(15;17) and inv(16).
  
  
  OBJECTIVE
  To study the clinical and cytogenetic data of patients with secondary myeloid neoplasms who took antineoplastic and/or immunosuppressive drugs or progressed from aplastic anemia.
  
  
  METHODS
  The clinical and cytogenetic characteristics of 42 patients diagnosed with secondary myeloid neoplasms in one institution were retrospectively evaluated. Of these, 25, 11 and 6 patients had had oncological diseases, aplastic anemia and other diseases, respectively. Conventional cytogenetic and FISH analyses were performed for monosomy 7.
  
  
  RESULTS
  The cytogenetic study was conclusive in 32 cases with 84.4% of clonal abnormalities. Monosomy 7 and complex karyotypes were present in 44.4% and 37%, respectively. A high prevalence of unbalanced abnormalities (96.3%) was observed. Monosomy 7 was more prevalent in patients with myelodysplastic syndromes/myeloid neoplasms after aplastic anemia (66.6%). The median survival after diagnosis of myeloid neoplasms was only 5.7 months. Normal cytogenetics was associated to better survival (p-value = 0.03). There was a slightly worse trend of survival for patients with complex karyotypes (p-value = 0.057). Abnormal karyotype was an independent risk factor for poor survival (p-value = 0.012).
  
  
  CONCLUSIONS
  This study enhances the importance of cytogenetic analysis of patients at the time of diagnosis of secondary myeloid neoplasms.
authors.affiliation: Cytogenetics Laboratory, Serviço de Hematologia do Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo - USP, São Paulo, SP, Brazil.
authors.forename: Roberta Sandra da Silva
authors.initials: RS
authors.lastname: Tanizawa
authors.forename: Cristina Aiko
authors.initials: CA
authors.lastname: Kumeda
authors.forename: Raymundo Soares
authors.initials: RS
authors.lastname: de Azevedo Neto
authors.forename: Aline de Medeiros
authors.initials: Ade M
authors.lastname: Leal
authors.forename: Patrícia de Barros
authors.initials: Pde B
authors.lastname: Ferreira
authors.forename: Elvira Deolinda Rodrigues Pereira
authors.initials: ED
authors.lastname: Velloso