Tröger and co-authors assume to have presented evidence proving that mistletoe treatment in patients with locally advanced or metastatic pancreatic carcinoma significantly improves quality of life compared with best supportive care (BSC). In the original publication (1) the authors claim that survival was significantly extended by this therapy. To publish the primary endpoint, survival, and the secondary endpoint, quality of life, separately (2), follows in the tradition of unnecessary multiple publications. Both statements are unsustainable because of the study’s serious methodological shortcomings.
Without blinding, it is not possible to make a valid statement with regard to quality of life and the chosen method of randomization using sealed envelopes does not meet the requirements of good study practice.
The study was terminated early after enrolment of approximately half of the intended number of patients. The authors do not mention that early termination may lead to significant overestimation of treatment effects, especially in small studies (3). The therapy standard at the time of the study was not adequately reported. Best supportive care is here a commonly used “euphemism” for doing without sensible disease-modifying therapies.
The authors declare financial support from the Swiss Cancer Research Association (Verein für Krebsforschung e. V. (VfK), Schweiz) which generates revenues from license fees received from Weleda AG for the preparation of the active substance and, at the same time, state that no conflict of interest exists.
Footnotes
Conflict of interest statement
The authors declare that no conflict of interest exists.
References
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