ObjectiveThis study aims to explore the variations and dynamics in the mental states of young patients with early breast cancer across different perioperative periods and to analyse how different surgical methods impact these patients' psychological well-being.MethodsA prospective observational study was conducted on young patients with early breast cancer who underwent surgery from March 2021 to March 2022. Mental status questionnaires were administered at four key time points: preoperatively, 1 month, 6 months and 1 year postoperatively. The collected data were statistically analysed to discern the psychological shifts in these patients throughout the perioperative timeline. The patients were categorized into either the breast-conserving or mastectomy group based on their surgical procedure, and their mental state scores during each phase were analysed to investigate the effects of different surgical methods on their psychological health.ResultsDuring the study period, 149 young patients with early breast cancer completed the four-phase questionnaire. Statistically significant differences were observed in self-evaluation, self-esteem, physiological state, fear of death, economic stress, negative emotion, and anxiety and depression among these patients across different periods. The baseline data revealed differences in marital status, place of residence and prior tumour history between the two surgical groups. Significant differences in self-evaluation, depression, self-esteem and positive emotions were found between the breast-conserving group and mastectomy groups.ConclusionBreast cancer presents significant physical and psychological challenges from diagnosis through treatment. Our findings indicate that young patients with early breast cancer experience varying degrees of psychological distress during the entire perioperative period, influencing their surgical choices and postoperative recovery. This study found that the psychological state of patients undergoing breast-conserving surgery is more favourable compared with that of patients who received mastectomies, particularly in terms of self-assessment, self-esteem, positive affect and depression levels.