At present wide-spread of cancer and high mortality caused by the disease (350000 people per year in Russia) make scientists search for new laboratory tests to diagnose malignant tumors. Thus, diagnostics of pre-tumor states when effective therapy is still possible is considered to be the most important problem. Diagnostics of stomach, lung and breast cancer is a particularly burning issue because of the difficulties of their early identification. In these cases precise monitoring seems possible only by using of complicated instrumental testing methods. All up—to—date paraclinic diagnostic methods (except the histologic one) may give considerable percentage of errors [1 , 2, 3]. Even the histologic method does not ensure full accuracy  due to a number ofsubjective and objective reasons. So, the need to develop a new methodology of pre—morphological diagnostics allowing to solve such an important problem as the character ofpathologic process identification is obvious. Thus, constantly increasing interest in optic methods of cancer diagnostics is understandable. First of all, it is caused by high sensitivity of these methods, possibility to examine tissue with minimal invasion through fiber-optic probes and harmlessness of probing radiation for human organism. One of the most precise researching methods in the given field is spectral analysis, in particular optical spectroscopy which allows to obtain considerable volume of significant information at investigation of biological object including human malignant tissue.