Mistletoe as a Therapeutic Option in Cancer Patients: a scoping review protocol

ABSTRACT Objective This scoping review aims to identify, map and provide an overview of the studies investigating the therapeutic use of Viscum Album L. (mistletoe) in cancer patients. By identifying pivotal patterns and research gaps in the existing literature on Viscum therapy, this review intends to offer valuable insights and supportive information to better inform future research efforts in this field. Introduction Cancer exerts a significant impact on global mortality, posing numerous challenges to public policies. The disease progression and the conventional treatment itself presents multifaceted health adversities to subjects. In response to these complexities, researchers have been exploring non-conventional therapeutic approaches, including phytotherapy. Mistletoe, a widely-used herbal medicine in oncology, is currently undergoing investigation for its potential adjuvant roles in both curative and palliative cancer care. Inclusion criteria We will consider studies that include individuals with cancer, irrespective of participant’s age or cancer type/stage, and who were subjected/exposed to interventions based on or incorporating Viscum album L. The review will consider clinical, quasi-experimental, and analytical observational studies, with no limitations on the time of intervention/exposure, treatment stage or geographic region. Methods This review will follow the methodological guidance of the JBI Manual for Evidence Synthesis for scoping reviews. The searches will be conducted in the following databases: MEDLINE (via PubMed), CENTRAL (via Cochrane Library), Embase (via Elsevier), Scopus, Web of Science Core Collection, CINAHL (via EBSCO), LILACS and SciELO. The search strategy will be adapted to the specificities of each of these databases, using thesaurus terms and synonyms related to the intervention (mistletoe) and the population (cancer), without restrictions on language or date of publication. The search for unpublished studies will be done in Google Scholar, preprint servers (medRxiv and bioRxiv) and trial registry platforms (Clinical Trials and International Clinical Trials Registry Platform), along grey literature in OpenGrey. Initially, eligibility criteria will be screened by two independent reviewers, assessing article titles and abstracts. Following finishing the full reading and inclusion determination, data extraction will be carried out by two independent reviewers. The results will be presented in narrative form and through tables and graphs.