Efficacy of perioperative repetitive transcranial magnetic stimulation for postoperative depression in breast cancer patients: study protocol for a single-center randomized controlled trial

Background Breast cancer (BC) is one of the most prevalent malignancies worldwide, and the perioperative period represents a vulnerable phase during which surgical stress and psychological burden may contribute to postoperative depression and impaired recovery. Repetitive transcranial magnetic stimulation (rTMS) is an established non-invasive neuromodulation technique for depressive disorders; however, evidence regarding its application for preventing postoperative depression (PD) in patients with breast cancer remains limited. Methods/design This single-center, prospective, randomized controlled study will enroll 182 patients scheduled for breast cancer surgery with preoperative depressive symptoms defined as a 17-item Hamilton Depression Rating Scale (HAMD-17) score ≥7. Participants will be randomly allocated to receive either active rTMS or sham stimulation. Active rTMS will be delivered over the left dorsolateral prefrontal cortex (DLPFC) at 10 Hz and 120% of the resting motor threshold. Two sessions of rTMS will be administered during the perioperative period, including one session one day before surgery and one session before surgery on the day of operation. Sham stimulation will mimic acoustic and sensory characteristics of active stimulation without delivering an effective magnetic field to the cortex. The primary outcome is the incidence of postoperative depression (PD) at postoperative day 3, operationally defined as the proportion of participants with preoperative depressive symptoms (HAMD-17 ≥7) who have a postoperative HAMD-17 score of 7 or above. Secondary outcomes include longitudinal changes in HAMD-17 scores at postoperative day 1, day 3, day 7, and 3 months, frailty status, sleep quality, postoperative pain intensity, and serum brain-derived neurotrophic factor (BDNF) levels in a randomly selected subset of participants. Discussion This trial will evaluate whether perioperative rTMS can reduce the incidence of postoperative depression and improve depressive symptom severity in breast cancer patients undergoing surgery. The findings may provide preliminary evidence regarding the potential efficacy and safety of ultra-brief perioperative rTMS and inform future neuromodulation strategies for perioperative affective symptom management in oncology populations. Clinical trial registration https://www.chictr.org.cn/index.html , identifier ChiCTR2500097808