Symptom clusters in colorectal cancer: a systematic review of assessment tools, statistical methods, and symptom patterns.

[PURPOSE] To summarize the assessment methodology, statistical analysis, and composition of symptom clusters in patients with colorectal cancer.

[METHODS] Published studies on symptom clusters in patients with colorectal cancer were identified through searches. A search was conducted for studies published between January 2001 and July 2024 using databases such as PubMed, Cochrane Library, Web of Science, CINAHL, Embase, and China National Knowledge Infrastructure. The quality of the studies was assessed using a set of criteria from the JBI Reviewers' Manual. A narrative synthesis of the findings was conducted.

[RESULTS] Eleven studies from seven countries were included, representing 4001 participants. The assessment tools and statistical analyses varied among the studies. Overall, the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ) and principal component analysis were the most frequently used tools. The most reported symptom clusters were (1) fatigue/lack of energy, anxiety/worry/nervousness, and depression/sadness/upset; (2) nausea, vomiting, and lack of appetite; (3) pain and sleep disorder/insomnia; and (4) pain/abdominal pain and feeling bloated.

[CONCLUSIONS] In addition to the more general fatigue-anxiety-depression symptom cluster, special attention should be given to colorectal cancer-specific clusters, such as nausea-vomiting-appetite loss and abdominal pain-feeling bloated. The identification of symptom clusters requires careful interpretation based on the assessment tools and statistical methods used. Future research is suggested to prioritize the use of disease-specific measures and advanced analytical approaches, such as network analysis, to enhance the understanding and clinical management of these clusters.