Cancer treatments can significantly affect a patient’s nutritional health, with chemotherapy causing changes in weight and body composition that can influence treatment outcomes. This study aims to examine the changes in weight and body composition during the first cycle of neoadjuvant chemotherapy and explore how these changes relate to factors such as gender, age, body fat percentage, tumor location, and time since diagnosis. This study involved 139 patients undergoing cancer treatment, with anthropometric data collected using standard techniques and body composition assessed through bioelectrical impedance analysis. Clinical details were retrieved from hospital records. Across all cancer types and stages, there were significant reductions in body mass index (BMI) and lean mass after four weeks of neoadjuvant chemotherapy (NAC), while fat mass and body fat percentage increased. The proportion of patients with low BMI, reduced muscle mass, and sarcopenic obesity also rose significantly. Approximately 62% of participants lost weight during the study. Men were more likely than women to experience muscle mass loss. Non-overweight individuals were more prone to both weight loss and muscle mass reduction compared to those who were overweight or obese. Patients with colorectal cancer had more than twice the chance of experiencing significant weight loss compared to those with other types of cancer. On the other hand, women with breast or uterine cancer were less likely to lose muscle mass than those with other types of cancer. These findings suggest that NAC can contribute to a higher risk of malnutrition, underlining the importance of early nutritional intervention to address changes in weight and body composition during cancer treatment.
