# Impact of robotic surgery on systemic immune-inflammation index in gastric cancer patients: a retrospective cohort study

## TL;DR

This study shows that robotic surgery for gastric cancer better preserves immune system function compared to traditional methods.

## Contribution

This is the first study to demonstrate robotic surgery's immune-preserving advantages using the systemic immune-inflammation index.

## Key findings

- Robotic surgery showed significantly lower systemic immune-inflammation index compared to laparoscopic and open surgery.
- Minimally invasive surgery (robotic+laparoscopic) had better immune biomarker outcomes than open surgery.
- Systemic immune-inflammation index had higher diagnostic accuracy in minimally invasive groups.

## Abstract

Robotic surgery has been gaining attention because of the physical and metabolic morbidity of the conventional open technique. The systemic immune-inflammation index has emerged as a recent and more reliable biomarker. In our single-center retrospective cohort study, we investigate systemic immune-inflammation index in robotic gastrectomy in order to show the advantageous effect on the immune system, which we think is the first study in the literature.

The study involved patients from a high-volume center for 32 months. The patients were allocated into three groups: patients with robotic (1), laparoscopic (2), and open surgery (3). Venous blood was derived on the postoperative 24th hour. The systemic immune-inflammation index scores were compared in three groups in terms of Group 1 vs. Groups 2 and 3, Groups 1 and 2 vs. Group 3, and compared with platelet-lymphocyte ratio, neutrophil–lymphocyte ratio scores.

Robotic surgery was performed in 55 patients, laparoscopic surgery in 13 patients, and open surgery in 248 patients. In the comparison of minimally invasive surgery (Groups 1+2) vs. open surgery (Group 3), systemic immune-inflammation index, platelet-lymphocyte ratio, and neutrophil–lymphocyte ratio were found to be significantly lower in the minimally invasive surgery group (p<0.05). The comparison between robotic surgery patients (Group 1) and patients with laparoscopy/open surgery (groups 2 and 3) showed that systemic immune-inflammation index, platelet-lymphocyte ratio, and neutrophil–lymphocyte ratio were significantly lower in Group 1 (p<0.05). neutrophil–lymphocyte ratio, platelet-lymphocyte ratio, and systemic immune-inflammation index values were analyzed by receiver operating characteristic curve test, and the area under curve value of systemic immune-inflammation index was found to be higher in minimally invasive surgery group (robotic+laparoscopic) (p<0.05).

The study reveals the superiority of robotic gastrectomy as a more feasible and high-quality procedure over conventional techniques in terms of better preservation of immune system function using a reliable and noninvasive serum biomarker.