A new algorithm for a better characterization and

Authors: Karima El AlaouiLasmaili ElHadi Djermoune JeanBaptiste Tylcz Dominique Meng François Plénat Noémie Thomas Béatrice Faivre

Publish Date: 2016/12/10

Volume: 20, Issue: 1, Pages: 149-162

PDF Link

Abstract

Antiangiogenics are widely used in cancer treatment in combination with chemotherapy and radiotherapy for their vascular effects Antiangiogenics are supposed to induce morphological and functional changes in the chaotic tumor vasculature that would help enhance the therapeutic efficacy of chemotherapy and radiotherapy through the amelioration of the drug delivery or the oxygenation in the tumor respectively However finding the best treatment sequence is not an easy task to achieve and no consensus has yet been established because of the lack of knowledge regarding when and for how long the vascular network is ameliorated The aim of this work was to develop a dedicated image processing algorithm able to analyze the vascular structures on optical microscopy images of the vascular network and to follow its fine modifications in vivo over time We applied this algorithm to follow the evolution of the vascular parameters vascularized tissue surface branches sprouts and length in response or not to antiVEGF therapy 10 mg/kg/day and determine precisely whether there is really a vascular “normalization” with antiVEGF therapy in comparison with the parameters extracted from healthy vascular networks We found that for this determination the choice of region of interest to analyze is critical as it is important to compare only microcirculation areas and avoid areas with arteriole–venule–capillary hierarchy The algorithm analysis allowed us to define a vascular “normalization” in treated tumors between 8 and 12 days of bevacizumab treatment that was confirmed by standard immunohistochemical analysis microvascular permeability assessment and immunohistological blood perfusion assessment

Keywords: