[Evaluation of cancer pain--possibility of biomarkers]

The accurate assessment of pain is needed to control cancer pain and its treatment. Pain itself is subjective experience and is difficult to estimate quantitatively. Until now, there is no precise method to quantitate the cancer pain objectively. First, we show the tools to assess cancer pain by patient's description, including visual analogue scales, verval rating scales and numerical rating scales and so on. These scales have been used to evaluate the intensity of clinical pain, however they cannot assess the quality of cancer pain and only McGill Pain Questionnaire (MPQ) has specificity for the qualitative and quantitative properties of clinical pain. Molecular biological approach has been advanced in the neuroscience field to find the candidate of neuropathic pain. In this article, we would like to show the results of the proteomics research for neuropathic pain. We also tried to discuss about the biomarker and its possibility whether it can reflect cancer pain and effect of cancer treatment.