Mantovani described inflammation as the 7th hallmark of cancer, citing its importance both for tumour development but also maintenance of the cancer state (Nature 2008). What is becoming clear is that inflammation has implications for symptom management as well.
Cancer cachexia is well recognised to have systemic inflammation at its core and possible therapies to treat this underlying inflammation are currently being investigated (preMENAC Study-PRC). Pain is also related to inflammation. This has been described as early as the 1st Century AD by the roman encyclopaedist Celcus. Recently the specific link between pain and inflammation in cancer has been described (Laird et al, Pain 2011).
In addition to pain and cachexia, inflammation has been suggested as a cause of some symptom clusters (pain, depression, fatigue) in cancer. This cluster is similar to animal models of cytokine induced sickness behaviour and further examination of this in human studies would be of interest.
In treating cancer symptoms, we treat from the front; once symptoms have developed symptoms are attenuated, where possible, with medication. As our understanding of inflammation in symptom development increases, inflammation may provide a target in treating cancer symptoms at their genesis.
Such an approach would be of interest and potentially therapeutic value. Studies fully exploiting the pro-inflammatory response as a target in the treatment of cancer symptoms are eagerly awaited.
Posted by Barry Laird, MD, University of Edinburgh, UK and NTNU, Norway.