Symptom clusters in patients with metastatic cancer: a literature review

This article reviews the literature reporting empirically determined symptom clusters in patients with metastatic cancer. A literature search was conducted on symptom clusters within heterogeneous metastatic cancer patient populations using MEDLINE, EMBASE, and CINAHL. Studies examining predetermined symptom clusters were excluded. A total of eight relevant studies published between 2005 and 2011 were identified. The number of symptom clusters extracted varied from two to eight clusters per study, comprising of two to eight symptoms per cluster. There were no clusters consistently identified within all eight studies. Notable differences in symptoms assessed, assessment tools, statistical analysis, patient demographics were observed between the studies. The lack of consensus among the inter-study symptom clusters are likely due to the differences in patient population as well as study methodology. Further exploration in metastatic symptom cluster research will ideally improve patient outcomes by facilitating improved symptom management in future clinical practice.