Patients with advanced cancer experience pain, fatigue, nausea, weakness, impaired appetite, sleep disturbances and drowsiness (Chen and Tseng).
Among 1000 advanced cancer patients the median number of symptoms experienced was 11 and pain occurred in 84% of patients (Gift).
Patients with advanced cancer rarely have symptoms in isolation but tend to experience them in clusters.
Correlates negatively with patient functioning.
Defined symptom cluster as 3 or more symptoms that occur (Dodd).
Cluster symptoms ore often inadequately treated in advanced cancer.
It is suggested that cytokines are the underlying cause of these symptoms acting at several levels including the brain-hypothalamic pituitary-adrenal axis alteration, sleep disturbance, psychological factors, muscle mass and strength, immunity and metabolism.
Cytokines are thought to be secreted by tumors and are a response of the host to the disease and its treatments, such as chemotherapy or radiation therapy.
Studies suggest corticosteroids may improve cancer symptom cluster (Yennurajalingam).