Cancer fatigue is a well-recognised, often intense symptom experienced both during and after treatment. Since cancer and ME/CFS share both fatigue and severe disability, researchers in Antwerp speculated that there could be other links between the two pathologies, particularly as regards immune abnormalities.
The key findings of their in-depth review, published in Anticancer Research in 2009, were that both conditions share abnormalities in the RNase L antiviral pathway and in the major intracellular mechanism NF-κB which regulates inflammatory and oxidative stress (see Table). In addition, natural killer cell malfunction has long been recognised as an important factor in the development and reoccurrence of cancer, and this has also been documented repeatedly in people with ME/CFS. The researchers point out that these immunological problems are clearly apparent and quite similar in both diseases.
While there are clear differences between cancer and ME/CFS — most prominently in cause, illness progression and mortality — the researchers are nevertheless intrigued by the shared immune abnormalities. It may be that these overlapping immune dysfunctions are involved in shaping some of the symptoms shared by both illnesses.
Reference: Immunological similarities between cancer and chronic fatigue syndrome: the common link to fatigue? Meeus M et al. Anticancer Res 2009 Nov; 29(11): 4717-26.