In this paper we show the results of multi-spectral Mueller Imaging applied to the analysis of human colon cancer in a
backscattering configuration with diffuse light illumination. The analyzed sample behaves as a pure depolarizer. The
depolarization power, for both healthy and cancerous zones, is lower for linearly than for circularly polarized incident
light for all used wavelengths and increases with increasing wavelength. Based on their visual staging and polarimetric
responses, we chose specific zones which we correlated to the histology of the corresponding cuts. The histological
examination shows that we see a multilayer interaction in both healthy and abnormal zones, if the light penetration depth
is sufficient. The measured depolarization depends on several factors: the presence or absence of tumor, the microscopic
structure of cancer (ratio between cellular density and stroma), its exophytic (budding) or endophytic (penetrating)
nature, its thickness, the degree of cancer penetration in deeper layers and the nature of healthy tissue left under
abnormal layers. These results demonstrate that multi-spectral Mueller imaging can provide useful contrasts for the quick
staging of human colon cancer ex-vivo, with additional information about cancerous zones with different microscopic
structures.
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