The effects of sarcopenia and sarcopenic obesity after pancreaticoduodenectomy in patients with pancreatic head cancer.

BACKGROUND: Recently, several studies have reported that sarcopenia and sarcopenic obesity (SO) could worsen postoperative complications after PD. This study aims to evaluate the effects of preoperative sarcopenia and SO following PD in pancreatic head cancer (PHD). METHODS: Preoperative sarcopenia and SO were assessed in 548 patients undergoing PD for PHC at Samsung Medical Centre between 2007 and 2016. The visceral adipose tissue-to-skeletal muscle ratio was calculated from cross-sectional visceral fat and muscle areas on preoperative CT images. The overall survival (OS) and rate of clinically relevant postoperative pancreatic fistula (CR-POPF) among postoperative complications were extracted from prospectively maintained databases. RESULTS: Preoperative sarcopenia was present in 252 patients (45.9%). The 5-year survival rates of patients with non-sarcopenia and sarcopenia were 28.4% and 23.4% (p = 0.046). Preoperative SO was present in 202 patients (36.9%). After multivariable analysis, the presence of SO was the only independent risk factor for CR-POPF (p = 0.018). CONCLUSION: Sarcopenia can be a risk factor affecting decreased OS after PD in patients with PHC. SO is the only predictive factor for CR-POPF after PD in patients with PHC. More observational studies are needed to evaluate the effects of sarcopenia and SO on survival after PD.

Nomogram for predicting postoperative pancreatic fistula.

BACKGROUND: Previous studies analyzed risk factors for postoperative pancreatic fistula (POPF) and developed risk prediction tool using scoring system. However, no study has built a nomogram based on individual risk factors. This study aimed to evaluate individual risks of POPF and propose a nomogram for predicting POPF. METHODS: From 2007 to 2016, medical records of 1771 patients undergoing pancreaticoduodenctomy were reviewed retrospectively. Variables with p < 0.05 in multivariate logistic regression analysis were included in the nomogram. Internal performance validation was executed using a repeated cross validation method. RESULTS: Of 1771 patients, 222 (12.5%) experienced POPF. In multivariable analysis, sex (p = 0.004), body mass index (BMI) (p < 0.001), ASA score (p = 0.039), preoperative albumin (p = 0.035), pancreatic duct diameter (p = 0.002), and location of tumor (p < 0.001) were identified as independent predictors for POPF. Based on these six variables, a POPF nomogram was developed. The area under the curve (AUC) estimated from the receiver operating characteristic (ROC) graph was 0.709 in the train set and 0.652 in the test set. CONCLUSIONS: A POPF nomogram was developed. This nomogram may be useful for selecting patients who need more intensified therapy and establishing customized treatment strategy.

Determination of irinotecan and its metabolite SN-38 in rabbit plasma and tumors using a validated method of tandem mass spectrometry coupled with liquid chromatography.

New tandem mass spectrometric method coupled with liquid chromatography (LC-MS/MS) has been developed to determine the total concentration of camptothecin derivatives (irinotecan and SN-38) regardless of inter-conversion phenomenon between carboxylate and lactone forms. At first, all sample solutions were acidified for 1h in order to completely convert CPT derivatives into their lactone forms and then CPT derivatives were extracted with organic solution containing diethyl ether and ethyl acetate (2:1, v/v) just after alkalization in the range pH 8.0-8.5 in acid-treated solutions. Analytes were separated on a reverse phase C18 column (150×2.1mm) and eluted isocratically with a mobile phase which consisted of acetonitrile-methanol-buffer (0.1% formic acid, 5mM ammonium formate) (3:4:3, v/v). CPT derivatives were monitored by tandem mass spectrometry in electrospay-positive ionization and multiple reaction mode programmed to the following transitions (m/z): '587.6→167.2' of CPT-11, '393.6→349.3' of SN-38 and '349.4→ 305.2' of CPT. The method was validated to have the proper linearity (r(2)>0.99) over the range of 5-1000ng/ml of CPT-11 and 1-250ng/ml of SN-38 with good accuracy (89.8-114.3%) and precision (less than 10%). In all stability tests, concentration of CPT-11 and SN-38 had been left in the acceptable range of 88.8-110.7% when sample solutions were acidified before determination of CPT derivatives. Newly developed LC-MS/MS method was suitable for the determination of CPT derivatives of both rabbit plasma and tumor tissues in the pharmacokinetic study.