Skeletal muscle mass associates with pancreaticoduodenectomy operative time in a sex-dependent manner.

Younger patient age was associated with increased pancreaticoduodenectomy operative time.

• The study cohort consisted of 68 patients who underwent pancreaticoduodenectomy with preoperative CTs available for body composition analysis.
• Patients were drawn from the first 211 consecutive patients enrolled in an institutional biobanking protocol with malignancies associated with pancreatectomy.
• Younger age was identified as one of three demographic/surgical variables associated with longer operative time.

Greater number of lymph nodes removed and the need for vascular repair were associated with increased pancreaticoduodenectomy operative time.

• These were identified alongside younger age as significant associations with operating time in the overall cohort.
• Vascular repair was used as a stratification variable in subsequent body composition analyses, with non-vascular repair cases (n = 56) analyzed separately.
• The need for vascular repair was treated as a confounder for body composition analyses.

Neither subcutaneous adipose tissue nor visceral adipose tissue was associated with pancreaticoduodenectomy operative time in surgeries without vascular repairs.

• Analysis was restricted to surgeries without vascular repairs (n = 56).
• Subcutaneous adipose tissue was not associated with surgery length (p = 0.80).
• Visceral adipose tissue was not associated with surgery length (p = 0.32).
• This finding was contrary to the study's hypothesis that greater adipose tissue would be associated with extended operative time.

Greater skeletal muscle mass showed a trend toward association with longer pancreaticoduodenectomy operative times overall.

• The association between skeletal muscle mass and operative time approached but did not reach conventional statistical significance (p = 0.051) in the full non-vascular-repair cohort (n = 56).
• Skeletal muscle was described as 'unique' among body composition variables in its relationship to operative time.
• This overall trend was later explained by a sex-dependent relationship operating in opposite directions.

Skeletal muscle mass was associated with pancreaticoduodenectomy operative time in a sex-dependent manner, with opposite directional relationships in females and males.

• For females, increased operative time was associated with greater skeletal muscle mass (p = 0.005).
• For males, increased operative time was associated with lower skeletal muscle mass (p < 0.001).
• This sexual dimorphism in the relationship between skeletal muscle and operative time was a key finding of the study.
• The authors suggest that assessment of skeletal muscle mass could prove useful in identifying patients at risk of prolonged pancreaticoduodenectomy operations.