title: Symptom clusters in patients with lung cancer: a literature review.
abstract: OBJECTIVE
  To provide a review of literature reporting empirically determined symptom clusters in lung cancer patients.
  
  
  METHODS
  We conducted a literature search on symptom clusters in lung cancer patients using MEDLINE, EMBASE and CINAHL. Studies examining the presence of predetermined clusters were excluded. The five relevant studies identified were published between 1997 and 2009.
  
  
  RESULTS
  Overall, the five studies reported significantly diverse findings with regards to symptom cluster quantity and composition in lung cancer patients. The number of symptom clusters extracted varied from one to four per study. The number of symptoms in a cluster ranged from two to 11. The only cluster that was consistently identified in two studies was composed of nausea and vomiting symptoms. Respiratory clusters identified in two studies were also comparable, containing both dyspnea and cough, among other symptoms. Methodological disparities, including differences in sample population characteristics, assessment tools and analytical methods, were evident in the five studies reviewed.
  
  
  CONCLUSIONS
  Symptom cluster exploration is a developing area of research in the oncology field and is promising in providing insights into diagnosis, prognostication and symptom management. Disparities in methodology are significant barriers to producing comparable results. These inconsistencies result in a lack of consensus in symptom clusters in lung cancer populations, thus impeding the determination of clinically relevant findings.
authors.affiliation: Rapid Response Radiotherapy Program, Odette Cancer Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, M4N 3M5, Canada.
authors.forename: Emily
authors.initials: E
authors.lastname: Chen
authors.forename: Janet
authors.initials: J
authors.lastname: Nguyen
authors.forename: Gemma
authors.initials: G
authors.lastname: Cramarossa
authors.forename: Luluel
authors.initials: L
authors.lastname: Khan
authors.forename: Andrew
authors.initials: A
authors.lastname: Leung
authors.forename: Steve
authors.initials: S
authors.lastname: Lutz
authors.forename: Edward
authors.initials: E
authors.lastname: Chow
mesh_terms: D016000:Cluster Analysis; D003371:Cough / Q000209:etiology; D004417:Dyspnea / Q000209:etiology; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis / Q000503:physiopathology*; D009325:Nausea / Q000453:epidemiology / Q000209:etiology; D012107:Research Design; D014839:Vomiting / Q000453:epidemiology / Q000209:etiology