Landscape analysis of oncology nutrition research among patients being treated for cancer

Recent efforts by numerous organizations and societies have found limited scientific evidence to support oncology nutrition guideline development. This project was undertaken to describe oncology nutrition studies that are underway or recently completed and to evaluate factors related to the completion and publication of study findings. Searches of ClinicalTrials.gov and the Australian New Zealand Clinical Trials Registry were performed in January 2025 using combinations of the terms: cancer, nutrition, diet, and oncology. Search results were merged and duplicates were removed using R/RStudio, and then, each entry was manually reviewed for eligibility in REDCap. Eligibility criteria were as follows: a study start date between January 2015 and December 2024, participants who were actively receiving cancer treatment, and a measure of diet/nutritional status and/or a nutrition intervention. Descriptive statistics, including stratified analyses, were conducted in R/RStudio. The database searches identified 1866 unique study listings. After exclusion criteria were applied, 444 studies met the inclusion criteria. Most studies (n = 352, 79.3%) were intervention studies. The vast majority of studies (n = 380, 85.6%) were funded by sources other than government (n = 48, 10.8%) or industry (n = 16, 3.6%) grants. Nine broad categories of study topics were identified, with the most common being intake of specific nutrients/supplements (n = 173), prehabilitation/perioperative nutrition (n = 153), quality of life, symptom/toxicity management (n = 136), and nutrition assessment, counseling, and education (n = 100). Median target enrollment for the included studies was 80 participants (range: 1-10,000). Less than a third of completed studies had published findings as of January 1, 2025. Larger, rigorously designed trials are needed for inclusion in future evidence-based guideline development efforts.