Patient-centered symptom clustering in advanced cancer patients

[[abstract]]To promote quality of life and achieve a good death is the core value of palliative care for advanced cancer patients. Although physical, psychological, and spiritual distress interferes with their quality of life, symptom management is the initial and basic care of advanced cancer patients. One of the most important characteristics of the symptoms of advanced cancer patients is multiple, concurrent and it tends to be moderate or severe in intensity. Research on these symptoms in the past focused on individual symptoms and their associated factors. This kind of individual symptom-oriented therapeutic strategy raises some important concerns, such as polypharmacy and drug side effects. Furthermore, emphasizing management of a single symptom at the expense of others may compromise individual quality of life, which results in the goal of palliative care not achieved. In recent years, a few researches on symptom management of advanced cancer patients have shifted from individual symptoms to symptom clusters. Symptom clusters are defined as three or more concurrent symptoms that are related to each other, or two or more related symptoms that occur simultaneously. The symptom clustering phenomenon has been verified by various statistical methods. Fatigue (anorexia-cachexia), neuropsychological, upper gastrointestinal, nausea and vomiting, aerodigestive, debility, and pain are common symptom clusters in advanced cancer. In addition to age, gender, and types of malignancies, anticancer therapy may be associated with different patterns of symptom clustering at various time points. Several lines of evidence have demonstrated that symptom clustering pattern is not only associated with quality of life but also functional status. We further demonstrated survival, functional performance, bone metastasis, pleural effusion, and ascites were associated with the symptom clustering pattern in advanced cancer patients. Although the underlying etiologies and mechanisms for the aggregation of symptoms are not clear, the concept of symptom clustering can be very useful in symptom assessment. We are able to dissect the interrelation among the symptoms in a cluster and target at the main symptom. A rational and exact symptom assessment is the first step to achieve appropriate and effective symptom management. Beside physical symptoms, psychological and spiritual distress should be considered in symptom clustering. After all, total suffering is the quintessential characteristic of advanced cancer patients. Symptom management could not be independent of psychological support and spirituality. For better quality of palliative care, it is warranted to further study symptom clustering in advanced cancer patients