Abstract
BACKGROUND: Breast cancer has become the most common malignancy worldwide. Experimental and, retrospective, clinical data indicate that anaesthetic technique might influence the risk of metastasis after cancer surgery by modulating the immune system. The purpose of this study is to investigate the effect of perioperative lidocaine injection on immune cells such as T lymphocytes and natural killer cells (NK cells) and the quality of postoperative recovery in breast cancer patients and to propose new ideas and relevant theoretical evidence for the selection of anesthetic protocols for perioperative tumor patients. METHODS: Women (n=68) undergoing primary breast tumour resection were randomly assigned to received 2% lidocaine (n=34; group L) or placebo (normal saline; n=34; group S). Venous blood was collected thirty minutes before surgery (T0), after tumor removal (T1), immediately after surgery (T2), 24 h after surgery (T3), and 48 h after surgery (T4). The percentages of NK cells and T lymphocyte subsets (CD3(+), CD4(+), CD8(+), CD4(+)/CD8(+)) in peripheral blood were detected by flow cytometry. Patients' quality of recovery-15 (QoR-15) scores were recorded by questionnaire before and 24 h after the operation, as well as intraoperative propofol and remifentanil dosages, the frequency of 24 h postoperative remedial analgesia, and the incidence of nausea and vomiting, dizziness, and chest tightness. RESULTS: There were 62 patients included in the study, and 60 patients were finally analyzed. The difference in the changing trend of NK cell levels in the 2 groups over time was statistically significant (F=7.675, P=0.008). The intraoperative changing trends of CD3(+) T cells, CD4(+) T cells, and the CD4(+)/CD8(+) ratio over time differed significantly between the 2 groups of patients (P<0.05), whereas the trends of CD8(+) T cells did not differ significantly (P>0.05). The QoR-15 score at 24 h after surgery was higher in Group L (128.50±20.25) than in Group S (117.50±19.50), and the difference was statistically significant (P=0.005). No adverse events such as cardiac arrhythmia and lidocaine toxicity occurred in both groups during the perioperative period. CONCLUSIONS: Continuous intravenous pumping of lidocaine during the perioperative period has little effect on immune function in breast cancer patients and promotes postoperative recovery. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2100050445.