The attention that the scientific world is rendering to the prostate is relevant because the increase of incidence and prevalence of the prostate pathology, either benign or malignant. They are a great number of biological factors intervening in the establishment, development and progression of malignant proliferative prostatic pathology (prostate carcinoma); a very relevant factor is vascularization, being the microvascular environment essential for the growth of prostate carcinoma. However, no rigorous, quantitative (stereologic) studies have been performed in this field. Besides, the prostate microvascular bed is a good model to apply tools of nonlinear analysis to characterize their possibly isotropic distribution in a 3D space, and the eventual changes in size and orientation or complexity in the development of pathological processes. In the present study, the next aims are intended:
1. Checking for the chaotic deterministic character of microvascularization in space-series of prostatic normal and cancer tissues.
2. Estimating microvessel fractal dimensions (correlation dimension, box counting dimension) and lacunarity, in the 3D oriented space-series to check existence of isotropy for these parameters, and comparing the results obtained in normal prostate with cancer.
3. Estimating unbiased stereological parameters as: Density of vascular length (Lv vasc) , the average tissue radium of vascular diffusion (ARD) , average microvascular diameter (AVD) and volume fraction of the stroma occupied by normal and pathological microvessels (Vv vasc), in all the space directions to state if the isotropy is conserved for these parameters, and comparing these parameters between normal and cancer prostate tissues.
The results suggest the existence of a low-dimensional deterministic chaos in both normal and cancer prostate tissues, being significantly higher the dimension of correlation and lacunarity estimates in cancer than in normal prostate, whereas the box counting fractal dimension was significantly lower in cancer than in normal prostate. No significant differences were observed between cancer and normal prostate respecting to stereological estimates as Lv vasc, AVD, and Vv vasc, however the ARD was significantly higher in controls than in cancer. The isotropy was conserved for all the non-linear and stereologic parameters through all the prostate regions from normal prostate.
We conclude that:
a)The microvascularization in both normal an cancer prostate tissues shows a chaotic deterministic character.
b) Non-linear parameters as correlation dimension and box counting dimension were useful to discriminate between normal and cancer microvessels from human prostate.
c) Stereological parameters related to the size of microvessels did not change in cancer prostate.
d) All the parameters employed in this study preserve the isotropy throughout all the regions of the normal human prostate.