The Influence of the Change of Body Composition After Neoadjuvant Treatment on Outcome After Pancreaticoduodenectomy for Pancreatic Cancer

Abstract

Introduction: Recently, several reported the usefulness of neoadjuvant treatment for pancreatic cancer. However, preoperative intensive therapy may lead to exacerbation of general condition. The influence of neoadjuvant treatment on the nutritional status is not well understood. The aim of this study is to determine the influence of the change of body composition on outcome after pancreaticoduodenectomy (PD) for pancreatic cancer. Methods:Patients Between 2005 and 2013, consecutive 38 patients (23 men) who underwent neoadjuvant chemotherapy with radiation (NAC-R), followed by PD for pancreatic cancer were enrolled. Median age was 68 years (range, 45-79). Preoperative treatment Gemcitabine based chemotherapy was performed in 28 patients at 300mg/m2 x 4 weeks. S-1 based in 10 patients at 60mg/m2 x 28 days. Radiation was performed 50 Gy in each patient. Assessment Before and after NAC-R, subcutaneous fat area (SFA), visceral fat area (VFA), and skeletal muscle area (SMA) were measured using computed tomography (CT) and calculated the amount of reduction. Patients were categorized according to the reduction rate as “Reduction group” and “normal group”. Receiver operating characteristics analysis was used to determine cut-off values. SFA and VFA were calculated at the level of the umbilicus using computed tomography, whereas SMA at the third lumber vertebra. Adipose tissue and skeletal muscle were identified and quantified by Hounsfield units (HUs) threshold of -190 to -30 and -30 to +150, respectively. Results: All SFA, VFA, and SMA were reduced after NAC-R. The median reduction rate of SFA was higher than that of VFA and SMA (-21.5% vs -10.0% and -2.5%). The SFA reduction group showed poor 3-year overall and recurrent-free survival compared with normal group (overall, 16.1% vs 38.3%; recurrent-free, 5.6% vs 20.4%), whereas the VFA and SMA reduction were not. Conclusion: In this study, we showed that the SFA reduction was a prognostic factor. Some proposed that the preoperative status of visceral adiposity or sarcopenia indicate poor prognostic factor. However, these ignored time-dependent change of body composition. The neoadjuvant treatment will become increasingly important therapeutics for pancreatic cancer. Therefore, reduction rate of body composition may become one of the most effective tolls for estimating prognosis. In conclusion, the reduction of SFA may indicate the poor prognosis of pancreatic cancer after PD.