Clinical impact of psoas muscle volume on the development of inguinal hernia after robot-assisted radical prostatectomy.

BACKGROUND

Sarcopenia, a syndrome characterized by the loss of skeletal muscle mass, has attracted attention in the field of oncology, as it reflects poor nutritional status. The present study aimed to determine the risk factors for postoperative inguinal hernia (PIH) development after robot-assisted laparoscopic radical prostatectomy (RARP) for prostate cancer, and discuss whether sarcopenia could be used as a sensitive predictor of PIH.

METHODS

We reviewed the medical records of 147 patients who underwent RARP at our institution. The psoas muscle volume (PMV), as an indicator of sarcopenia, was quantified from computed tomography images using a 3-dimensional image analysis system. Multivariate cox regression analyses were performed to identify independent predictors of PIH, including pre- and peri-operative factors.

RESULTS

The mean PMV was 393 cm, and the correlation coefficient between PMV and body mass index was 0.37 (p < 0.01). The PIH-free rate at 2 years postoperatively was 78.2% among all patients. The multivariate analysis revealed that a PMV < 350 cm was a significant risk factor for PIH (p = 0.03; hazard ratio 2.19). Body mass index, age, prostate volume, lymph node dissection, nerve sparing, rectus muscle thickness, and console time were not related to PIH development. The PIH-free rate at 2 years postoperatively was 83.4% and 68.9% in patients with a PMV ≥ 350 cm and < 350 cm, respectively (p < 0.05).

CONCLUSIONS

PIH occurred significantly more frequently in patients with a PMV < 350 cm than in patients with a PMV ≥ 350 cm, and a low PMV was an independent risk factor for PIH. Thus, urologists should pay attention to the cumulative incidence of IH after RARP, especially in patients with a PMV < 350 cm.