Rapid decline in visceral adipose tissue over 1 month is associated with poor prognosis in patients with unresectable pancreatic cancer

Background Involuntary weight loss related to cachexia is common in patients with advanced cancer, but the association between body composition changes and survival is still unclear in pancreatic cancer. Methods We retrospectively reviewed the clinical outcomes of 55 patients with advanced pancreatic cancer undergoing palliative therapy or best supportive care (BSC). The skeletal muscle index (SMI), visceral adipose tissue index (VATI), subcutaneous adipose tissue index (SATI), and visceral to subcutaneous adipose tissue area ratio (VSR) were calculated based on the cross‐sectional area on two sets of computed tomography images obtained at cancer diagnosis and 1 month later before treatment. The prognostic value of body composition indexes at diagnosis and the changes in those indexes over 1 month was then evaluated. Results In total, 45 patients (81.8%) received chemotherapy, chemoradiation, or radiation therapy, whereas the remaining patients underwent BSC. There were 27 patients (49.1%) who had low SMI at cancer diagnosis. Univariate analysis showed no significant associations between the baseline body composition indexes including SMI, VATI, SATI, and VSR and survival. Meanwhile, male sex (HR, 2.79; 95% CI, 1.16–6.71, p = 0.022) and higher decrease in VATI over 1 month (HR, 2.41; 95% CI, 1.13–5.13, p = 0.023) were identified as independent risk factors for mortality in multivariate analysis. Conclusion Rapid decline in VAT over 1 month is closely associated with poorer survival in unresectable advanced pancreatic cancer. A short‐term assessment of body composition changes may be a rational approach to predict prognosis in these patients. We evaluated the prognostic impact of body composition changes in patients with unresectable pancreatic cancer. We revealed that rapid decline in vsceral adipose tissue over 1 month is closely associated with poorer survival in those patients.