Bock, P.R., Hanisch, J., Matthes, H., & Zanker, K.S. (2014). Targeting inflammation in cancer-related-fatigue: A rationale for mistletoe therapy as supportive care in colorectal cancer patients. Inflammation and Allergy Drug Targets, 13, 105–111. 

To examine fatigue levels in patients supported by a mistletoe preparation compared to patients who did not receive mistletoe

Data were extracted from the medical records of patients from the time of diagnosis or surgery (visit 1), during postoperative chemotherapy or chemoradiotherapy (visit 2), and at the end of postoperative therapy (visit 3). Patient complains related to fatigue and symptoms of inflammation were noted by the physician via interview. The results of patients allocated to mistletoe therapy were compared to those of the control patients. Mistletoe was provided as an injectable extract preparation that was given subcutaneously at a total average dose of 16–20 mg per week.

• N = 324  
• AGE = Not provided
• MALES: Not provided, FEMALES: Not provided
• KEY DISEASE CHARACTERISTICS: All patients had colorectal cancer and were receiving 5-fluorouracil-based chemotherapy.

• SITE: Multi-site    
• SETTING TYPE: Not specified    
• LOCATION: Germany

• PHASE OF CARE: Active antitumor treatment

Retrospective, observational cohort study

Specific measurements were not described. Signs of inflammation and cancer-related fatigue were apparently coded by physicians as “yes” or “no” to indicate the presence of clinical signs.

There was a significantly increased odds ratio of suffering with fatigue among patients in the control group at visits 2 and 3 (p < 0.001). However, by visit 2, 85% of those in the mistletoe group had dropped out, and by visit 3, only 16 patients remained in the mistletoe group. The results regarding inflammation were not described.

This report provides insufficient evidence regarding the effects of mistletoe therapy on cancer-related fatigue.

• Small sample (< 30)
• Risk of bias (no control group)
• Risk of bias (no blinding)
• Risk of bias (no random assignment)
• Measurement/methods not well described
• Measurement validity/reliability questionable
• Subject withdrawals ≥ 10%  
• Other limitations/explanation: The study design, lack of clear objective methods to measure outcomes, and extremely high drop-out rate limit the usefulness of the findings reported. The actual dosages, timing, and duration of mistletoe therapy were not described.

This study does not provide any strong evidence regarding the efficacy of mistletoe extract for the management of cancer-related fatigue, and it does not provide evidence regarding the impact of this therapy on inflammatory markers. Inflammation is a suggested mechanism that may influence fatigue in patients with cancer, and mistletoe extract has been proposed as an intervention to reduce inflammation. Well-designed studies examining the potential effects of mistletoe extract in these areas are needed.