RESUMO
AIM: This study aims to evaluate the effect of early nutritional intervention on adverse clinical events in women with breast cancer undergoing neoadjuvant chemotherapy. DESIGN AND SETTINGS: This is a randomized clinical trial performed at the beginning of neoadjuvant chemotherapy for women with breast cancer treated at an oncology referral center (Brazil) and followed until the end of radiotherapy period, at least. Registered under ClinicalTrials.gov Identifier no. RBR-3SHHXS. METHODS: Participants were allocated to a control group - CG (nutritional guidance on healthy eating practices) or an intervention group - IC (nutritional guidance and individualized food plan). Chemotherapy toxicity (primary endpoint) was considered a precocious adverse clinical event and it was evaluated by self-reported gastrointestinal symptoms observed at any time during the first three cycles of treatment. Post-surgical complications, radiotherapy toxicity, and weight change were considered long-term adverse events. RESULTS: 34 women (19 in the IG and 15 in the CG) were evaluated. The early nutritional intervention was associated with low gastrointestinal chemotoxicity (nausea, vomiting, and constipation, p < 0.001, p < 0.048, and p < 0.024, respectively). However, there were no statically significant differences between both groups in the presence of long-term adverse events (radiotherapy toxicity-88.2% vs 76.9%, weight loss-21.1% vs 26.7% for IC and CG respectively, p > 0.05 for both). CONCLUSION: The early nutritional intervention was associated with a low frequency of precocious events, but not with long-term adverse events in women with breast cancer during treatment.