Study of the distribution of microvessels in normal and pathologic prostate using an information-based similarity...

Categorizing biologic signals by analysis of symbolic sequences was employed in the study of prostate microvessels. The estimates of the volume fraction of the vessels immunostained to Factor-VIII was mapped to binary sequences. The distance between sequences was estimated by comparing the rank and frequency of repetitive elements. These measurements were applied to detect whether there are unique microvascular patterns for each individual, and to search for patterns describing prostate microvessels of different conditions. Normal prostate, benign prostate hyperplasia and prostate carcinoma groups were studied. All the specimens were immunostained to F-VIII and strips formed by adjacent quadrats were explored. At each point of the long axis of the strip, the V(V) F-VIII was calculated. These values were processed with the information-based similarity software to estimate the dissimilarity between two space series. The following comparisons were carried out: intrasubject versus intragroup distances; intragroup distances among the groups studied and intergroup distances. The distance defined between a vessels immunostained to Factor-VIII space series and its randomized surrogate was considered as an index of the nonrandomness of the space series. These indices were compared for all the groups. We conclude that (a) The information-based similarity analysis can be adapted to vessels immunostained to Factor-VIII space series from prostate microvessels. (b) There are no unique microvascular patterns associated with each individual. (c) There are characteristic patterns describing the microvessels from normal prostate, benign prostate hyperplasia and carcinoma. (d) This method is able to account for the differences between prostate cancer and both normal and benign prostate conditions, with respect to the microvessel patterns.