Analgesia and Wound Healing Assessment Following Topical Morphine Applied to Patients With Cutaneous Cancer Related Pain

Cutaneous cancer-related pain is difficult to treat. These patients are often prescribed high systemic dosages of opioids. Yet, many patients continue to report pain while experiencing dose-limiting side effects. An alternative approach to systemic administration is to apply topical medications. The advantage of topical application is the potential of achieving good analgesia using low dosages with few, if any, systemic side effects. Current clinical data indicates, that topically applied morphine has an analgesic effect in patients with severe pain and that it may even improve wound healing. The clinical reports so far have been either case studies or double blind randomly controlled trials with a very small sample size of patients. There is still a great deal of information which is lacking about this modality of treatment regarding on the one hand, the mechanism of action and on the other, clinical issues. For example, is the mechanism of the effect actually peripheral? What is the adequate dose of analgesic medication for different types of skin conditions? Wound healing has not been quantified. We will apply morphine topically to skin wounds of cancer and evaluate the effect of the treatment on pain, side effects, quantify wound healing, quantify morphine and its metabolites in blood and urine. Should well controlled studies, demonstrate all or any of the peripheral effects of topical morphine, clinical application of this treatment modality would be possible. This could contribute towards better treatment of these patients, who have pain which is difficult to treat and can, at times, be intractable.