title: Quantification of fractal dimension and Shannon's entropy in histological diagnosis of prostate cancer.
abstract: BACKGROUND
  Prostate cancer is a serious public health problem that affects quality of life and has a significant mortality rate. The aim of the present study was to quantify the fractal dimension and Shannon's entropy in the histological diagnosis of prostate cancer.
  
  
  METHODS
  Thirty-four patients with prostate cancer aged 50 to 75 years having been submitted to radical prostatectomy participated in the study. Histological slides of normal (N), hyperplastic (H) and tumor (T) areas of the prostate were digitally photographed with three different magnifications (40x, 100x and 400x) and analyzed. The fractal dimension (FD), Shannon's entropy (SE) and number of cell nuclei (NCN) in these areas were compared.
  
  
  RESULTS
  FD analysis demonstrated the following significant differences between groups: T vs. N and H vs. N groups (p < 0.05) at a magnification of 40x; T vs. N (p < 0.01) at 100x and H vs. N (p < 0.01) at 400x. SE analysis revealed the following significant differences groups: T vs. H and T vs. N (p < 0.05) at 100x; and T vs. H and T vs. N (p < 0.001) at 400x. NCN analysis demonstrated the following significant differences between groups: T vs. H and T vs. N (p < 0.05) at 40x; T vs. H and T vs. N (p < 0.0001) at 100x; and T vs. H and T vs. N (p < 0.01) at 400x.
  
  
  CONCLUSIONS
  The quantification of the FD and SE, together with the number of cell nuclei, has potential clinical applications in the histological diagnosis of prostate cancer.
authors: Faculdade de Medicina de São José do Rio Preto (FAMERP), Av, Brig, Faria Lima 5416, 15090-000, São José do Rio Preto, SP, Brazil. pedro.arruda@sbu.org.br.
authors: Pedro Francisco Ferraz
authors: PF
authors: de Arruda
authors: Márcio
authors: M
authors: Gatti
authors: Fernando Nestor
authors: FN
authors: Facio
authors: José Germano Ferraz
authors: JG
authors: de Arruda
authors: Roberto Douglas
authors: RD
authors: Moreira
authors: Luiz Otávio
authors: LO
authors: Murta
authors: Laísa Ferraz
authors: LF
authors: de Arruda
authors: Moacir Fernandes
authors: MF
authors: de Godoy