The impact of skeletal muscle wasting during neoadjuvant chemotherapy on postoperative anastomotic leakage in patients with esophageal cancer

Background: Sarcopenia is defined by low muscle mass and low muscle strength and is a prognostic factor of unfavorable outcomes in various diseases. The purpose of this study is to examine the correlation between skeletal muscle wasting (SMW) during neoadjuvant chemotherapy (NAC) and postoperative complications in patients with esophageal cancer, particularly in relation to anastomotic leakage.

Methods: The present study involved 99 patients with thoracic esophageal cancer and esophago-gastric junctional cancer who received NAC followed by radical esophagectomy between August 2008 to June 2019, and who were pStage 0-III. Patient demographics and clinical variables were retrospectively reviewed. For assessing the extent of SMW, the rate of change in skeletal muscle mass index (SMI) was measured from CT images at the level of the third lumbar vertebra. Factors associated with postoperative complications were also examined.

Results: The median rate of change in total SMI in patients was - 1.87%. The decreased rates in SMI of the side abdominal muscles and rectus abdominis were significantly greater than that of the psoas major (side abdominal muscles: p = 0.0084, rectus abdominis: p = 0.036). Multivariate analysis showed a decreased rate in SMI, especially in the erector spinae muscle, and the Charlson comorbidity index (CCI) was significantly associated with Grade IIIa of higher anastomotic leakage (Grade ≥ IIIa) (SMI cutoff (favorable): ≤ - 7.84, p = 0.0040; CCI cutoff (favorable): ≥ 2, p = 0.0032).

Conclusion: In patients with esophageal cancer, SMI tend to decrease during NAC treatment. It is therefore important to prevent the additional impact that SMW during NAC has on postoperative anastomotic leakage.