Difficult cancer pain: an examination of physical and psychological components

AIMS: The aims of this thesis are to characterise clinically, neuropathic cancer pain and CIBP, to examine the relationship between cancer pain and depression, to explore the relationship between pain and systemic inflammation and the possibility of pain, depression and fatigue existing, as a symptom cluster.METHODS: A combination of observational study, systematic review, longitudinal study and secondary data analysis methodology were utilised, as appropriate to the specific area being examined.RESULTS: In neuropathic cancer pain and cancer induced bone pain, worst pain is most closely associated with the impact of pain on function. In these pain syndromes, breakthrough pain is often of rapid onset, severe intensity and short duration. The systematic review demonstrated that there is insufficient evidence to support an interdependent relationship between pain and depression. The longitudinal study demonstrated that as pain improves, there is a trend towards an improvement in depression and there is an improvement in the Hospital Anxiety and Depression Scale (HADS) score. Pain, depression and fatigue cluster together in cancer patients although there is insufficient information to suggest systemic inflammation as an underlying cause. There is, however, a significant relationship between pain and systemic inflammation.CONCLUSIONS: The difficult cancer pain syndromes of neuropathic cancer pain and cancer induced bone pain are best assessed using "worst pain" as a measure of the impact of pain on function. Pain and depression in cancer are likely to be related to one another although further research is needed to confirm this. Pain, depression and fatigue exist together as a symptom cluster in specific groups of cancer patients. Pain is related to systemic inflammation in cancer