Abstract
BACKGROUND AND PURPOSE: The objective of this systematic review was to establish an overview of changes in body composition as a result of early breast cancer treatment. Patient/material and methods: Five databases (PubMed, CINAHL, Embase, Web of Science and Cochrane Library) were used for identifying studies and papers. Selection criteria included: > 18 years, early breast cancer stage 0-III and measurement of body composition with either dual X-ray absorptiometry (DXA), magnetic resonance imaging (MRI) or computed tomography (CT). Studies using only bioelectrical impedance were excluded. RESULTS: A total of 734 studies were screened; 29 studies were full-text reviewed, and 10 studies were included in this systematic review, with a total of n = 1,062. Included studies were published from 2018 to 2024. This review found consistent increases in fat mass between 3.3 and 9.2% across the studies. Results for lean body mass were less consistent. Two studies examined visceral fat mass, yet both found statistically significant increases. INTERPRETATION: This systematic review identified consistent increases in total fat mass and visceral fat across the included studies, regardless of whether the treatment involved chemotherapy, endocrine therapy or a combination of both. In contrast, findings related to lean body mass were considerably less consistent. The results highlight the potential implications following breast cancer treatment and emphasise the importance of metabolic monitoring, diet and exercise to increase quality of life and prevent recurrence. This review also highlights the need for more research on the topic, as the included studies exhibit substantial heterogeneity, making it difficult to draw definitive conclusions.