Background: The changes in body composition that occur in response to therapy for localized pancreatic ductal adenocarcinoma (PDAC) and during the early survivorship period, as well as their clinical significance, are poorly understood.
Methods: One hundred twenty-seven consecutive patients with PDAC who received preoperative therapy followed by pancreatoduodenectomy (PD) at a single institution between 2009 and 2012 were longitudinally evaluated. Changes in skeletal muscle (SKM), visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT) were measured on serial computed tomography images obtained upon presentation, prior to pancreatectomy, and approximately 3 and 12 months after surgery.
Results: Prior to therapy, patients' mean baseline BMI was 26.5 ± 4.7 kg/m2 and 63.0% met radiographic criteria for sarcopenia. During a mean 5.4 ± 2.3 months of preoperative therapy, minimal changes in SKM (- 0.5 ± 7.8%, p > 0.05), VAT (- 1.8 ± 62.6%, p < 0.001), and SAT (- 4.8 ± 27.7%, p < 0.001) were observed. In contrast, clinically significant changes were observed on postoperative CT compared to baseline anthropometry: SKM - 4.1 ± 10.7%, VAT - 38.7 ± 30.2%, and SAT - 24.1 ± 22.6% (all p < 0.001) and these changes persisted at one year following PD. While anthropometric changes during preoperative therapy were not independently associated with survival, SKM gain between the postoperative period and one-year follow-up was associated with improved overall survival (OR 0.50, 95% CI 0.29-0.87).
Conclusions: In contrast to the minor changes that occur during preoperative therapy for PDAC, significant losses in key anthropometric parameters tend to occur over the first year following PD. Ongoing SKM loss in the postoperative period may represent an early marker for worse outcomes.
Keywords: Body composition; Neoadjuvant therapy; Pancreatectomy; Pancreatic ductal adenocarcinoma; Pancreatoduodenectomy; Whipple.