Prediction of pancreatic anastomotic failure after pancreatoduodenectomy: the use of preoperative, quantitative computed tomography to measure remnant pancreatic volume and body composition. Ann Surg. 2013;257:512-519. [PMID: 23241871 DOI: 10.1097/sla.0b013e31827827d0]

Decreased Skeletal Muscle Volume Is a Predictive Factor for Poorer Survival in Patients Undergoing Surgical Resection for Pancreatic Ductal Adenocarcinoma

BACKGROUND

The aim of this study was to investigate the impact of decreased skeletal muscle (SM) volume on survival outcomes in patients undergoing surgical resection for pancreatic ductal adenocarcinoma (PDAC).

METHODS

Between March 2000 and February 2015, 323 patients who underwent upfront surgical resection for PDAC were identified from the Mayo Clinic SPORE in Pancreatic Cancer. Body composition data, including SM area, subcutaneous adipose tissue area, and visceral adipose tissue area were calculated using an abdominal computed tomography (CT) image at the third lumbar spinal level. The body composition data were normalized by patients' height (e.g., SM index, cm²/m²) and analyzed as continuous variables. Clinicopathological findings and body composition data at initial diagnosis were evaluated for association with overall survival and recurrence-free survival.

RESULTS

Because the median SM index was significantly different between males vs. females (49.9 cm²/m² [range, 32.0-70.3] vs. 39.4 cm²/m² [range, 29.2-66.2], P < 0.001), it was standardized for each sex and used for further analyses. Parameters independently associated with a shorter overall survival were a larger tumor size (P = 0.007), a greater tumor extent (P = 0.037), a higher carbohydrate antigen 19-9 level (P < 0.001), and a smaller sex-standardized SM index (P = 0.011). Parameters independently associated with a shorter recurrence-free survival were female sex (P = 0.029), a larger tumor size (P < 0.001), a higher carbohydrate antigen 19-9 level (P = 0.001), and a smaller sex-standardized SM index (P = 0.007).

CONCLUSIONS

A smaller sex-standardized SM index is a predictive factor for shorter overall and recurrence-free survival in PDAC patients undergoing surgery.

Developing and validating a center-specific preoperative prediction calculator for risk of pancreaticoduodenectomy

BACKGROUND

The American College of Surgeons (ACS) Surgical Risk Calculator predicts postoperative risk based on preoperative variables. The ACS model was compared to an institution-specific risk calculator for pancreaticoduodenectomy (PD).

METHODS

Observed outcomes were compared with those predicted by the ACS and institutional models. Receiver operating characteristic (ROC) analysis evaluated the models' predictive ability. Institutional models were evaluated with retrospective and prospective internal validation.

RESULTS

Brier scores indicate equivalent aggregate predictive ability. ROC values for the institutional model (ROC: 0.675-0.881, P < 0.01) indicate superior individual event occurrence prediction (ACS ROC: 0.404-0.749, P < 0.01-0.860). Institutional models' accuracy was upheld in retrospective (ROC: 0.765-0.912) and prospective (ROC: 0.882-0.974) internal validation.

CONCLUSIONS

Identifying higher-risk patients allows for individualized care. While ACS and institutional models accurately predict average complication occurrence, the institutional models are superior at predicting individualized outcomes. Predictive metrics specific to PD center volume may more accurately predict outcomes.

Comparing Western and Eastern criteria for sarcopenia and their association with survival in patients with pancreatic cancer

BACKGROUND & AIMS

Sarcopenia and cachexia are associated with pancreatic cancer and serve as important adverse prognostic factors. Body composition can be analyzed by routine computed tomography (CT) for cancer staging and has been used to study many types of cancer. The CT measurements are robust, but the diagnostic criteria for sarcopenia vary among different studies. Age, sex and race are important factors that affect muscle and fat masses. This study aimed to analyze the effect of different sarcopenia diagnostic criteria on the prognosis of patients with pancreatic cancer.

METHODS

Patients with newly diagnosed pancreatic cancer at National Taiwan University Hospital between October 2013 and October 2016 were retrospectively reviewed in this study. Body composition was assessed using cross-sectional CT images to calculate the total skeletal muscle (TSM) index. The concordance and interobserver variability of the TSM measurements were evaluated using both the Western criteria and the Eastern criteria. Kaplan-Meier analyses and the Cox proportional hazard ratio with two different diagnostic criteria for sarcopenia were used to compare the effect on overall survival (OS).

RESULTS

A total of 146 patients with pancreatic cancer were enrolled. The TSM index measured by the Western institute was highly correlated with that measured by the Eastern institute (r = 0.953, p < 0.001). The prevalence of sarcopenia in the patient group at baseline was 66.4% (97/146) by the Western criteria and 11.0% (16/146) by the Eastern criteria, and only low agreement was found between the Western and Eastern criteria (Kappa value = 0.028, p = 0.149). Patients who were sarcopenic by the Western criteria showed no significant difference in OS versus those who were not sarcopenic (p = 0.807). However, patients who were sarcopenic by the Eastern criteria showed a significant difference in OS versus those who were not sarcopenic in a univariate analysis (p = 0.008) and multivariate analysis after adjustment for AJCC stage (p = 0.014).

CONCLUSIONS

Our study demonstrates that different diagnostic criteria may result in different diagnoses and that sarcopenia is an important poor prognostic factor for pancreatic cancer when appropriate diagnostic criteria are selected.

Preoperative imaging evaluation of pancreatic pathologies for the objective prediction of pancreatic fistula after pancreaticoduodenectomy

In performing pancreaticoduodenectomy (PD) or when conducting clinical trials involving PD procedure, a universal platform for predicting the risk of postoperative pancreatic fistula (POPF) is indispensable. In this article, the most significant imaging studies that focused on the objective preoperative assessment of pancreatic pathologies in association with the occurrence of POPF after PD were reviewed. Several recently developed imaging modalities can objectively predict the occurrence of POPF after PD by assessing the elasticity, fibrosis, and fatty infiltration of the pancreas. These valuable imaging modalities include: (1) acoustic radiation force impulse ultrasound (US) electrography which provides information about the elastic properties of the pancreas; (2) contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) with/without contrast-enhancement which reflect the histological degree of pancreatic fibrosis; and (3) multi-detector row CT and/or MRI which reflects the microscopic fatty infiltration of the pancreas. The precise and objective preoperative risk assessment of POPF enables surgeons to customize appropriate management strategies for individual patients undergoing PD. This would be also beneficial for stratifying patients for enrolment in relevant studies that involve pancreatic head resection, as objective criteria could be set for the definitive evaluation of collected data related to surgical outcomes across different institutions and surgeons.

Impact of Sarcopenic Obesity on Failure to Rescue from Major Complications Following Pancreaticoduodenectomy for Cancer: Results from a Multicenter Study

BACKGROUND

Failure to rescue (FTR) is a quality-of-care indicator in pancreatic surgery, but may also identify patients who may not tolerate major postoperative complications despite being treated with best available care. Previous studies found that high visceral adipose tissue-to-skeletal muscle ratio is associated with poor outcomes following pancreaticoduodenectomy (PD). The aim of the study is to assess the impact of sarcopenic obesity on occurrence of FTR from major complications in cancer patients undergoing PD.

METHODS

Prospectively collected data from three high-volume hospitals were reviewed. Total abdominal muscle area (TAMA) and visceral fat area (VFA) were assessed at preoperative staging computed tomography scan. Sarcopenic obesity was defined as high VFA/TAMA ratio. FTR was defined as postoperative mortality following major complication.

RESULTS

120 patients with major complications were included. FTR occurred in 23 (19.2%) patients. The "seminal" complications leading to FTR were pancreatic or biliary fistula-related sepsis (n = 14), postoperative pancreatic fistula (POPF)-related hemorrhage (n = 5), and duodenojejunal anastomosis leak-related sepsis (n = 1). On univariate analysis, older age [odds ratio (OR) 3.5, p = 0.034], American Society of Anesthesiologists (ASA) score 3+ (OR 4.2, p = 0.005), cardiovascular disease (OR 3.3, p = 0.013), low serum albumin (OR 2.6, p = 0.042), sarcopenic obesity (OR 4.2, p = 0.009), POPF (OR 3.1, p = 0.027), and cardiorespiratory complications (OR 3.7, p = 0.011) were significantly associated with FTR. On multivariate analysis, sarcopenic obesity [OR 5.7, 95% confidence interval (CI) 1.6-20.7, p = 0.008], ASA score 3+ (OR 4.1, 95% CI 1.2-14.3, p = 0.025), and pancreatic fistula (OR 3.2, 95% CI 1.0-10.2, p = 0.045) were independently associated with FTR.

CONCLUSION

Sarcopenic obesity, low preoperative physical status, and occurrence of pancreatic fistula are associated with significantly higher risk of FTR from major complications after PD.

Validation study of a new semi-automated software program for CT body composition analysis

BACKGROUND

Computed tomography (CT) has been increasingly used to quantify abdominal muscle and fat in clinical research studies, and multiple studies have shown importance of body composition in predicting clinical outcome. The purpose of study is to compare newly developed semi-automated software (BodyCompSlicer) to commercially available validated software (Slice-O-Matic) for CT body composition analysis.

METHODS

CT scans of abdomen at L3 level in 30 patients were analyzed by two reviewers and using two softwares (BodyCompSlicer and Slice-O-Matic). Body composition analysis using BodyCompSlicer was semi-automated. The program automatically segmented subcutaneous fat (SF), skeletal muscle (SM), and visceral fat (VF) areas. Reviewers manually corrected the segmentation using computer-mouse interface as necessary. Body composition analysis using Slice-O-Matic was performed by manually segmenting each area using computer-mouse interface (brush tool). After segmentation, SM, SF, and VF areas were calculated using CT attenuation thresholds. Inter-observer and inter-software variability of measurements were analyzed using intraclass correlation coefficients (ICC) and coefficient of variation (COV).

RESULTS

Inter-observer ICC and COV using BodyCompSlicer were 0.997 and 1.5% for SM, 1.000 and 0.8% for SF, and 1.000 and 1.0% for VF, whereas those using Slice-O-Matic were 0.993 and 2.5% for SM, 0.995 and 3.1% for SF, and 0.999 and 2.3% for VF. Inter-software ICCs and COV were 0.995-0.995 and 2.0-2.1% for SM, 0.991-0.994 and 3.4-3.9% for SF, and 0.998-0.998 and 2.8-3.3% for VF. Time to analyze 30 cases was 70-100 min and 150-180 min using BodyCompSlicer and Slice-O-Matic, respectively.

CONCLUSION

BodyCompSlicer is comparable to Slice-O-Matic for CT body composition analysis.

Radiographic sarcopenia predicts postoperative infectious complications in patients undergoing pancreaticoduodenectomy

BACKGROUND

Recently, skeletal muscle depletion (sarcopenia) has been reported to influence postoperative outcomes after certain procedures. This study investigated the impact of sarcopenia on postoperative outcomes following pancreaticoduodenectomy (PD).

METHODS

We performed a retrospective study of consecutive patients (n = 219) who underwent PD at our institution between January 2007 and May 2013. Sarcopenia was evaluated using preoperative computed tomography. We evaluated postoperative outcomes and the influence of sarcopenia on short-term outcomes, especially infectious complications. Subsequently, multivariate analysis was used to assess the impact of prognostic factors (including sarcopenia) on postoperative infections.

RESULTS

The mortality, major complication, and infectious complication rates for all patients were 1.4%, 16.4%, and 47.0%, respectively. Fifty-five patients met the criteria for sarcopenia. Sarcopenia was significantly associated with a higher incidence of in-hospital mortality (P = 0.004) and infectious complications (P < 0.001). In multivariate analyses, sarcopenia (odds ratio = 3.43; P < 0.001), preoperative biliary drainage (odds ratio = 2.20; P = 0.014), blood loss (odds ratio = 1.92; P = 0.048), and soft pancreatic texture (odds ratio = 3.71; P < 0.001) were independent predictors of postoperative infections.

CONCLUSIONS

Sarcopenia is an independent preoperative predictor of infectious complications after PD. Clinical assessment combined with sarcopenia may be helpful for understanding the risk of postoperative outcomes and determining perioperative management strategies.

Rectal Gas Volume Measured by Computerized Tomography Identifies Evacuation Disorders in Patients With Constipation

BACKGROUND & AIMS

Approximately one third of patients who present to gastroenterology care with constipation have rectal evacuation disorders. We aimed to compare rectal gas volume, measured by computerized tomography (CT), in constipated patients with and without rectal evacuation disorders.

METHODS

In a retrospective study, we collected data from 1553 patients with constipation, evaluated over 20 years. We analyzed data from 141 patients evaluated by anorectal manometry, balloon expulsion tests, and colon transit tests, collecting records of abdominal and pelvic CT examinations. Patients were classified into 3 subgroups: those with rectal evacuation disorders, slow-transit constipation, or normal-transit constipation. Two observers used standard CT software to identify variable regions of interest on each cross-sectional CT image that contained rectum and measured areas of gas in each slice; they then summated entire volumes of rectal gas. For the 3 groups, we compared rectal gas volume, maximal rectal gas transaxial area (measured by CT), and area of rectal gas (vertical) on the 2-dimensional abdominal film (scout) using the Kruskal-Wallis test.

RESULTS

The intraclass correlation coefficient between 2 observers' measurements of rectal gas volume was 0.99 (P < .001). There were overall group differences in rectal gas volume and the maximal rectal gas transaxial area (both P < .001). The median rectal gas volume was higher in patients with rectal evacuation disorders (13.84 cm³) than in patients with slow-transit (2.51 cm³) or normal-transit constipation (1.33 cm³, both P < .05). Similarly, the area of rectal gas, which correlated with the maximal rectal gas transaxial area (Spearman correlation coefficient, 0.7; P < .001), showed overall 3-group differences (P = .033), with greater areas of rectal gas on the abdominal scout film in patients with rectal evacuation disorders than in those with normal-transit constipation.

CONCLUSIONS

In an analysis of patients with constipation, we found rectal gas volume, determined by abdominal CT imaging, to be greater in patients with than without rectal evacuation disorders.

Low skeletal muscle radiation attenuation and visceral adiposity are associated with overall survival and surgical site infections in patients with pancreatic cancer

BACKGROUND

Cancer cachexia and skeletal muscle wasting are related to poor survival. In this study, quantitative body composition measurements using computed tomography (CT) were investigated in relation to survival, post-operative complications, and surgical site infections in surgical patients with cancer of the head of the pancreas.

METHODS

A prospective cohort of 199 patients with cancer of the head of the pancreas was analysed by CT imaging at the L3 level to determine (i) muscle radiation attenuation (average Hounsfield units of total L3 skeletal muscle); (ii) visceral adipose tissue area; (iii) subcutaneous adipose tissue area; (iv) intermuscular adipose tissue area; and (v) skeletal muscle area. Sex-specific cut-offs were determined at the lower tertile for muscle radiation attenuation and skeletal muscle area and the higher tertile for adipose tissues. These variables of body composition were related to overall survival, severe post-operative complications (Dindo-Clavien ≥ 3), and surgical site infections (wounds inspected daily by an independent trial nurse) using Cox-regression analysis and multivariable logistic regression analysis, respectively.

RESULTS

Low muscle radiation attenuation was associated with shorter survival in comparison with moderate and high muscle radiation attenuation [median survival 10.8 (95% CI: 8.8-12.8) vs. 17.4 (95% CI: 14.7-20.1), and 18.5 (95% CI: 9.2-27.8) months, respectively; P < 0.008]. Patient subgroups with high muscle radiation attenuation combined with either low visceral adipose tissue or age <70 years had longer survival than other subgroups (P = 0.011 and P = 0.001, respectively). Muscle radiation attenuation was inversely correlated with intermuscular adipose tissue (r_p  = -0.697, P < 0.001). High visceral adipose tissue was associated with an increased surgical site infection rate, OR: 2.4 (95% CI: 1.1-5.3; P = 0.027).

CONCLUSIONS

Low muscle radiation attenuation was associated with reduced survival, and high visceral adiposity was associated with an increase in surgical site infections. The strong correlation between muscle radiation attenuation and intermuscular adipose tissue suggests the presence of ectopic fat in muscle, warranting further investigation. CT image analysis could be implemented in pre-operative risk assessment to assist in treatment decision-making.

A novel preoperative predictor of pancreatic fistula using computed tomography after distal pancreatectomy with staple closure

PURPOSE

A thick pancreas has proven to be a conspicuous predictor of pancreatic fistula (PF) following distal pancreatectomy (DP) using staples. Other predictors for this serious surgical complication currently remain obscure. This study sought to identify novel predictors of PF following DP.

METHODS

One hundred and twenty-two patients were retrospectively assessed to determine the correlation between PF occurrence and the clinicopathological findings and radiologic data from preoperative computed tomography (CT). CT assessments included the thickness of the pancreas (TP) and pancreatic CT number (pancreatic index; PI), calculated by dividing the pancreatic CT by the splenic CT density.

RESULTS

Twenty-four patients (19.7%) developed a clinically relevant PF. TP was identified as an independent risk factor for PF in multivariate analyses (odds ratio 1.17; P = 0.0095). In subgroup analyses, a lower PI in a thick pancreas was a significant predictor of PF (P = 0.032). The combination of these two prediction parameters, known as the TP-to-PI ratio (TPIR), showed a significantly better prediction ability than TP alone (area under the receiver operating characteristic curve for the incidence of PF, TPIR 0.80 vs. TP 0.69; P = 0.037).

CONCLUSION

Combining the CT number with TP substantially improves the prediction ability for the incidence of PF following DP with staple use.

Body Mass Index and Stump Morphology Predict an Increased Incidence of Pancreatic Fistula After Pancreaticoduodenectomy

BACKGROUND

A majority of factors associated with the occurrence of clinical relevant postoperative pancreatic fistula (CR-POPF) after pancreaticoduodenectomy (PD) can only be identified intra- or postoperatively. There are no reports for assessing the morphological features of pancreatic stump and analyzing its influence on CR-POPF risk after PD preoperatively.

METHOD

A total of 90 patients underwent PD between April 2012 and May 2014 in our hospital were included. Preoperative computed tomographic (CT) images were imported into the Medical Image Three-Dimensional Visualization System (MI-3DVS) for acquiring the morphological features of pancreatic stump. The demographics, laboratory test and morphological features of pancreatic stump were recorded prospectively. The clinical course was evaluated focusing on the occurrence of pancreatic fistula as defined by the International Study Group on Pancreatic Fistula (ISGPF). Logistic regression analysis was used to identify independent predictors of CR-POPF.

RESULTS

CR-POPF occurred in 18 patients (14 grade B, 4 grade C). In univariate analysis, male gender (P = 0.026), body mass index (BMI) ≥ 25.3 kg/m(2) (P = 0.002), main pancreas duct diameter (MPDD) < 3.1 mm (P = 0.005), remnant pancreatic parenchymal volume (RPPV) > 27.8 mL (P < 0.001), and area of cut surface (AOCS) > 222.3 mm(2) (P < 0.001) were associated with an increased risk of CR-POPF. In multivariate analysis, BMI ≥ 25.3 kg/m(2) (OR 12.238, 95 % CI 1.822-82.215, P = 0.010) and RPPV > 27.8 mL (OR 12.907, 95 % CI 1.602-104.004, P = 0.016) were the only independent risk factors associated with CR-POPF. A cut-off value of 27.8 mL for RPPV established based on the receiver operating characteristic (ROC) curve, which was the strongest single predictive factor for CR-POPF, with a sensitivity and specificity of 77.8 and 86.1 %, respectively. The area under the ROC curve of RPPV was 0.770 (95 % CI 0.629-0.911, P < 0.001).

CONCLUSIONS

Our study demonstrated that CR-POPF is correlated with BMI and RRPV. MI-3DVS provides us a novel and convenient method for measuring the RPPV. Preoperative acquisition of RPPV and BMI may help the surgeons in fitting postoperative management to patient's individual risk after PD.

Modified Frailty Index Predicts Morbidity and Mortality After Pancreaticoduodenectomy

BACKGROUND

Pancreatic cancer is a disease of older adults, who may present with limited physiologic reserve. The authors hypothesized that a frailty index can predict postoperative outcomes after pancreaticoduodenectomy (PD).

METHODS

All patients who underwent PD were identified in the 2005-2012 NSQIP Participant Use File. Patients undergoing emergency procedures, those with an American Society of Anesthesiologists (ASA) classification of five, and those with a diagnosis of preoperative sepsis were excluded from the study. A modified frailty index (mFI) was defined by 11 variables within the National Surgical Quality Improvement Program (NSQIP) previously used for the Canadian Study of Health and Aging-Frailty Index. An mFI score of 0.27 or higher was defined as a high mFI. Uni- and multivariate analyses were performed to evaluate postoperative outcomes.

RESULTS

This study enrolled 9986 patients (age 65 ± 12 years, 48.8% female) who underwent PD. Of these patients, 6.4% (n = 637) had a high mFI (>0.27). Increasing mFI was associated with higher prevalence of postoperative morbidity (p < 0.001) and 30-days mortality (p < 0.001). In the univariate analysis, high mFI was associated with increased morbidity (odds ratio [OR] 1.68; 95% confidence interval [CI] 1.43-1.97; p < 0.001) and 30-days mortality (OR 2.45; 95% CI 1.74-3.45; p < 0.001). After adjustment for age, sex, ASA classification, albumin level, and body mass index (BMI), high mFI remained an independent preoperative predictor of postoperative morbidity (OR 1.544; 95% CI 1.289-1.850; p < 0.0001) and 30-days mortality (OR 1.536; 95% CI 1.049-2.248; p = 0.027).

CONCLUSIONS

High mFI is associated with postoperative morbidity and mortality after PD and can aid in preoperative risk stratification.

A high visceral adipose tissue-to-skeletal muscle ratio as a determinant of major complications after pancreatoduodenectomy for cancer

OBJECTIVE

Complication rates after pancreatic resections remain high despite improvement in perioperative management. The effects of body composition and the relationship among different body compartments on surgical morbidity are not comprehensively investigated. The aim of this study was to assess whether the evaluation of different body compartments and their relationship was associated with the development of major postoperative complications after pancreatoduodenectomy (PD) for cancer.

METHODS

We retrospectively analyzed 124 patients who underwent PD and had a staging computed tomography (CT) scan at our center. CT scan was used to measure abdominal skeletal muscle area and volume, as well as visceral fat area (VFA) and volume. The total abdominal muscle area (TAMA) was then normalized for height. The severity of complications was assessed. Univariate and multivariate analyses were performed to investigate correlations between the above variables and postoperative complications. The receiver operating characteristic curve methodology was used to investigate the predictive ability of each parameter.

RESULTS

Major complications occurred in 42 patients (33.9%). The prevalence of sarcopenia was 24.2%. Regression analyses revealed no correlation between abdominal muscular and adipose tissue areas. Univariate analysis showed that the depletion of muscle area normalized for height was not per se predictive of complications (P = 0.318). Multivariate logistic regression showed that the VFA/TAMA was the only determinant of major complications (odds ratio, 3.20; 95% confidence interval, 1.35-7.60; P = 0.008). The model predictive performance was 0.735 (area under the curve) with a sensitivity of 64.3% and a specificity of 74.4%.

CONCLUSION

Sarcopenic obesity is a strong predictor of major complications after PD for cancer.

Enhanced recovery pathways in pancreatic surgery: State of the art

Pancreatic surgery is being offered to an increasing number of patients every year. Although postoperative outcomes have significantly improved in the last decades, even in high-volume centers patients still experience significant postoperative morbidity and full recovery after surgery takes longer than we think. In recent years, enhanced recovery pathways incorporating a large number of evidence-based perioperative interventions have proved to be beneficial in terms of improved postoperative outcomes, and accelerated patient recovery in the context of gastrointestinal, genitourinary and orthopedic surgery. The role of these pathways for pancreatic surgery is still unclear as high-quality randomized controlled trials are lacking. To date, non-randomized studies have shown that care pathways for pancreaticoduodenectomy and distal pancreatectomy are safe with no difference in postoperative morbidity, leading to early discharge and no increase in hospital readmissions. Hospital costs are reduced due to better organization of care and resource utilization. However, further research is needed to clarify the effect of enhanced recovery pathways on patient recovery and post-discharge outcomes following pancreatic resection. Future studies should be prospective and follow recent recommendations for the design and reporting of enhanced recovery pathways.

Three-dimensional simulation of pancreatic surgery showing the size and location of the main pancreatic duct

PURPOSE

We performed three-dimensional (3D) surgical simulation of pancreatic surgery, including the size and location of the main pancreatic duct on the resected pancreatic surface.

METHODS

The subjects of this retrospective analysis were 162 patients who underwent pancreatic surgery. This cohort was sequentially divided into a "without-3D" group (n = 81) and a "with-3D" group (n = 81). We compared the pancreatic duct diameter and its location, using nine sections in a grid pattern, with the intraoperative findings. The perioperative outcomes were also compared between patients who underwent pancreaticoduodenectomy (PD) and those who underwent distal pancreatectomy (DP).

RESULTS

There were no significant differences in the main pancreatic duct diameter between the 3D-simulated values and the operative findings. The 3D-simulated main pancreatic duct location was consistent with its actual location in 80 % of patients (65/81). In comparing the PD and DP groups, the intraoperative blood loss was 1174 ± 867 and 817 ± 925 ml in the without-3D group, and 828 ± 739 and 307 ± 192 ml in the with-3D group, respectively (p = 0.024, 0.026).

CONCLUSION

The 3D surgical simulation provided useful information to promote our understanding of the pancreatic anatomy, including details on the size and location of the main pancreatic duct.

The Standardization of Pancreatoduodenectomy: Where Are We?

Pancreaticoduodenectomy (PD) represents an important challenge for surgeons due to the complexity of the operation, requirement for technical skills and experience, and postoperative management involving important and life-threatening complications. Despite efforts to reduce mortality in high-volume centers, the morbidity rate is still high (approximately 40-50%). The PD standardization process of surgical aspects and preoperative and postoperative settings is essential to permit pancreatic surgeons to communicate in the same language, compare experiences and results, and to improve the short- and long-term outcomes. The aim of this article is to assess the state of the art practices for important matters of debate for PD (the role of mini invasive approach, the definition and the role of mesopancreas, the extent of lymphadenectomy, the different methods of reconstructions, the prophylactic drainage of the abdominal cavity), and to suggest possible future studies.

Effect of sarcopenia and visceral obesity on mortality and pancreatic fistula following pancreatic cancer surgery

BACKGROUND

Analytical morphometric assessment has recently been proposed to improve preoperative risk stratification. However, the relationship between body composition and outcomes following pancreaticoduodenectomy is still unclear. The aim of this study was to assess the impact of body composition on outcomes in patients undergoing pancreaticoduodenectomy for cancer.

METHODS

Body composition parameters including total abdominal muscle area (TAMA) and visceral fat area (VFA) were assessed by preoperative staging CT in patients undergoing pancreaticoduodenectomy for cancer. Perioperative variables and postoperative outcomes (mortality or postoperative pancreatic fistula) were collected prospectively in the institutional pancreatic surgery database. Optimal stratification was used to determine the best cut-off values for anthropometric measures. Multivariable analysis was performed to identify independent predictors of 60-day mortality and pancreatic fistula.

RESULTS

Of 202 included patients, 132 (65·3 per cent) were classified as sarcopenic. There were 12 postoperative deaths (5·9 per cent), major complications developed in 40 patients (19·8 per cent) and pancreatic fistula in 48 (23·8 per cent). In multivariable analysis, a VFA/TAMA ratio exceeding 3·2 and American Society of Anesthesiologists grade III were the strongest predictors of mortality (odds ratio (OR) 6·76 and 6·10 respectively; both P < 0·001). Among patients who developed major complications, survivors had a significantly lower VFA/TAMA ratio than non-survivors (P = 0·017). VFA was an independent predictor of pancreatic fistula (optimal cut-off 167 cm(2) : OR 4·05; P < 0·001).

CONCLUSION

Sarcopenia is common among patients undergoing pancreaticoduodenectomy. The combination of visceral obesity and sarcopenia was the best predictor of postoperative death, whereas VFA was an independent predictor of pancreatic fistula.

Pancreatic Steatosis and Fibrosis: Quantitative Assessment with Preoperative Multiparametric MR Imaging

PURPOSE

To evaluate the diagnostic performance of multiparametric pancreatic magnetic resonance (MR) imaging, including the T2*-corrected Dixon technique and intravoxel incoherent motion (IVIM) diffusion-weighted (DW) imaging, in the quantification of pancreatic steatosis and fibrosis, with histologic analysis as the reference standard, and to determine the relationship between MR parameters and postoperative pancreatic fistula.

MATERIALS AND METHODS

This retrospective study was approved by the institutional review board, and the informed consent requirement was waived. A total of 165 patients (93 men, 72 women; mean age, 62 years) underwent preoperative 3-T MR imaging and subsequent pancreatectomy (interval, 0-77 days). Fat fractions, IVIM DW imaging parameters (true diffusion coefficient [D], pseudodiffusion coefficient [D*], and perfusion fraction [f]), pancreas-to-muscle signal intensity ratios on unenhanced T1-weighted images, and pancreatic duct sizes were compared with the fat fractions and fibrosis degrees (F0-F3) of specimens. In 95 patients who underwent pancreatoenteric anastomosis, MR parameters were compared between groups with clinically relevant postoperative pancreatic fistula and those without. The relationship between postoperative pancreatic fistula and MR parameters was evaluated by using logistic regression analysis.

RESULTS

Fat fractions at MR imaging showed a moderate relationship with histologic findings (r = 0.71; 95% confidence interval: 0.63, 0.78). Patients with advanced fibrosis (F2-F3) had lower D*([39.72 ± 13.64] ×10(-3)mm(2)/sec vs [32.50 ± 13.09] ×10(-3)mm(2)/sec [mean ± standard deviation], P = .004), f (29.77% ± 8.51 vs 20.82% ± 8.66, P < .001), and unenhanced T1-weighted signal intensity ratio (1.43 ± 0.26 vs 1.21 ± 0.30, P < .001) than did patients with F0-F1 disease. Clinically relevant fistula developed in 14 (15%) of 95 patients, and f was significantly associated with postoperative pancreatic fistula (odds ratio, 1.17; 95% confidence interval: 1.05, 1.30).

CONCLUSION

Multiparametric MR imaging of the pancreas, including imaging with the T2*-corrected Dixon technique and IVIM DW imaging, may yield quantitative information regarding pancreatic steatosis and fibrosis, and f was shown to be significantly associated with postoperative pancreatic fistulas.

Calculating the risk of a pancreatic fistula after a pancreaticoduodenectomy: a systematic review

BACKGROUND

A post-operative pancreatic fistula (POPF) is a major cause of morbidity and mortality after a pancreaticoduodenectomy (PD). This systematic review aimed to identify all scoring systems to predict POPF after a PD, consider their clinical applicability and assess the study quality.

METHOD

An electronic search was performed of Medline (1946-2014) and EMBASE (1996-2014) databases. Results were screened according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and quality assessed according to the QUIPS (quality in prognostic studies) tool.

RESULTS

Six eligible scoring systems were identified. Five studies used the International Study Group on Pancreatic Fistula (ISGPF) definition. The proposed scores feature between two and five variables and of the 16 total variables, the majority (12) featured in only one score. Three scores could be fully completed pre-operatively whereas 1 score included intra-operative and two studies post-operative variables. Four scores were internally validated and of these, two scores have been subject to subsequent multicentre review. The median QUIPS score was 38 out of 50 (range 16-50).

CONCLUSION

These scores show potential in calculating the individualized patient risk of POPF. There is, however, much variation in current scoring systems and further validation in large multicentre cohorts is now needed.

A Simple Method to Evaluate Whether Pancreas Texture Can Be Used to Predict Pancreatic Fistula Risk After Pancreatoduodenectomy

INTRODUCTION

Soft pancreas is one of the most important risk factor for postoperative pancreatic fistula after pancreatoduodenectomy. The aim of this study is to investigate whether pancreatic attenuation index utilized to assess the pancreatic texture with computed tomography can be used to predict the risk of developing a clinically relevant postoperative pancreatic fistula after pancreatoduodenectomy.

METHODS

We reviewed 76 consecutive patients undergoing pancreatoduodenectomy between 2012 and 2014. The pancreatic attenuation index is found by dividing the pancreas density by the spleen density achieved with non-enhanced computed tomography. The independent predictors of clinically relevant postoperative pancreatic fistula were investigated.

RESULTS

Clinically relevant postoperative pancreatic fistula occurred in 13 patients (17.1%). The group of patients with postoperative pancreatic fistula is compared with the group of patients without postoperative pancreatic fistula in terms of age, gender, body mass index, the American Society of Anesthesiologists (ASA) score, smoking, alcohol consumption, medical comorbidities, preoperative biliary drainage, type of anastomosis, and pancreatic duct size and pancreatic attenuation index. Univariate analyses have shown a significant difference in relation to chronic obstructive pulmonary disease and pancreatic attenuation index. The multivariate analyses showed that only pancreatic attenuation index was associated with a high postoperative pancreatic fistula rate (P = 0.012).

CONCLUSION

A preoperative non-contrast computed tomography scan evaluating pancreatic attenuation index could help to predict the occurrence of clinically significant postoperative pancreatic fistula after pancreatoduodenectomy.

Preoperative Computed Tomography to Predict and Stratify the Risk of Severe Pancreatic Fistula After Pancreatoduodenectomy

The aim of this article is to assess whether measures of abdominal fat distribution, visceral density, and antropometric parameters obtained from computed tomography (CT) may predict postoperative pancreatic fistula (POPF) occurrence.We analyzed 117 patients who underwent pancreatoduodenectomy (PD) and had a preoperative CT scan as staging in our center. CT images were processed to obtain measures of total fat volume (TFV), visceral fat volume (VFV), density of spleen, and pancreas, and diameter of pancreatic duct. The predictive ability of each parameter was investigated by receiver-operating characteristic (ROC) curves methodology and assessing optimal cutoff thresholds. A stepwise selection method was used to determine the best predictive model.Clinically relevant (grades B and C) POPF occurred in 24 patients (20.5%). Areas under ROC-curves showed that none of the parameters was per se significantly predictive. The multivariate analysis revealed that a VFV >2334 cm, TFV >4408 cm, pancreas/spleen density ratio <0.707, and pancreatic duct diameter <5 mm were predictive of POPF. The risk of POPF progressively increased with the number of factors involved and age.It is possible to deduce objective information on the risk of POPF from a simple and routine preoperative radiologic workup.

Correlation between preoperative imaging and intraoperative risk assessment in the prediction of postoperative pancreatic fistula following pancreatoduodenectomy

BACKGROUND

Prediction of postoperative pancreatic fistula (POPF) can be carried out with the intraoperative assessment of pancreatic consistency (PC) and via pancreatic duct width (iPDW). Preoperative computed tomography (CT) calculated pancreatic remnant volume (PRV) and duct width (rPDW) have also been shown to offer useful information about the risk of POPF.

OBJECTIVE

The objective of this study was to determine the predictive value of the preoperative radiological features as compared with the intraoperative risk estimation for the subsequent development of POPF.

METHOD

All patients undergoing pancreatoduodenectomy between September 2007 and March 2012 at the Karolinska University Hospital Stockholm were included. PRV and rPDW were determined on preoperative CT and in parallel, intraoperative PC and iPDW of the remnant pancreas were independently assessed.

RESULTS

A total of 296 consecutive pancreatoduodenectomies were included. POPF occurred in 45 patients (15.2 %). Of those with a preoperatively calculated PRV < 23.0 cm(3), 2.8 % developed POPF compared with 25.7 % of those with a corresponding volume > 46.0 cm(3). In patients with an rPDW > 7.0 mm, 4.1 % had a POPF as compared with 38.7 % for those with rPDW < 2.0 mm. The POPF risk estimates based on PRV and rPDW and the intraoperative risk assessments were found to be identical (p < 0.001). In the receiver operating characteristic analysis, area under the curve was 0.80 (95 % confidence interval [CI] 0.72-0.87) and 0.80 (95 % CI 0.72-0.88) for the CT-based and intraoperative risk prediction models, respectively.

CONCLUSIONS

Preoperative CT-based and intraoperative gland risk assessments offer comparable predictive information on the risk of POPF after pancreatoduodenectomy. These results imply that accurate POPF risk estimation can be carried out in the preoperative setting to opt for improved patient selection into relevant research protocols and the availability of surgical expertise and techniques.

Risk factors and outcomes of postoperative pancreatic fistula after pancreatico-duodenectomy: an audit of 532 consecutive cases

BACKGROUND

Pancreatic fistula (PF) remains the most challenging complication after pancreaticoduodenectomy (PD). The purpose of this study was to identify the risk factors of PF and delineate its impact on patient outcomes.

METHODS

We retrospectively reviewed clinical data of 532 patients who underwent PD and divided them into PF group and no PF group. Risk factors and outcomes of PF following PD were examined.

RESULTS

PF was found in 65 (12.2%) cases, of whom 11 were classified into ISGPF grade A, 42 grade B, and 12 grade C. Clinically serious postoperative complications in the PF versus no PF group were mortality, abdominal bleeding, bile leak, intra-abdominal abscess and pneumonia. Univariate and multivariate analysis showed that blood loss ≥ 500 ml, pancreatic duct diameter ≤ 3 mm and pancreaticojejunostomy type were independent risk factors of PF after PD.

CONCLUSIONS

Blood loss ≥ 500 ml, pancreatic duct diameter ≤ 3 mm and pancreatico-jejunostomy type were independent risk factors of PF after PD. PF was related with higher mortality rate, longer hospital stay, and other complications.

Morbidity, mortality, cost, and survival estimates of gastrointestinal anastomotic leaks

BACKGROUND

Anastomotic leak, a potentially deadly postoperative occurrence, particularly interests surgeons performing gastrointestinal procedures. We investigated incidence, cost, and impact on survival of anastomotic leak in gastrointestinal surgical procedures at an academic center.

STUDY DESIGN

We conducted a chart review of American College of Surgeons NSQIP operative procedures with gastrointestinal anastomosis from January 1, 2003 through April 30, 2006. Each case with an American College of Surgeons NSQIP 30-day postoperative complication was systematically reviewed for evidence of anastomotic leak for 12 months after the operative date. We tracked patients for up to 10 years to determine survival. Morbidity, mortality, and cost for patients with gastrointestinal anastomotic leaks were compared with patients with anastomoses that remained intact.

RESULTS

Unadjusted analyses revealed significant differences between patients who had anastomotic leaks develop and those who did not: morbidity (98.0% vs. 28.4%; p < 0.0001), length of stay (13 vs. 5 days; p ≤ 0.0001), 30-day mortality (8.4% vs. 2.5%; p < 0.0001), long-term mortality (36.4% vs. 20.0%; p ≤ 0.0001), and hospital costs (chi-square [2] = 359.8; p < 0.0001). Multivariable regression demonstrated that anastomotic leak was associated with congestive heart failure (odds ratio [OR] = 31.5; 95% CI, 2.6-381.4; p = 0.007), peripheral vascular disease (OR = 4.6; 95% CI, 1.0-20.5; p = 0.048), alcohol abuse (OR = 3.7; 95% CI, 1.6-8.3; p = 0.002), steroid use (OR = 2.3; 95% CI: 1.1-5.0; p = 0.027), abnormal sodium (OR = 0.4; 95% CI, 0.2-0.7; p = 0.002), weight loss (OR = 0.2; 95% CI, 0.06-0.7; p = 0.011), and location of anastomosis: rectum (OR = 14.0; 95% CI, 2.6-75.5; p = 0.002), esophagus (OR = 13.0; 95% CI, 3.6-46.2; p < 0.0001), pancreas (OR = 12.4; 95% CI, 3.3-46.2; p < 0.0001), small intestine (OR = 6.9; 95% CI, 1.8-26.4; p = 0.005), and colon (OR = 5.2; 95% CI, 1.5-17.7; p = 0.009).

CONCLUSIONS

Significant morbidity, mortality, and cost accompany gastrointestinal anastomotic leaks. Patients who experience an anastomotic leak have lower rates of survival at 30 days and long term.

Is routine drainage necessary after pancreaticoduodenectomy?

With the development of imaging technology and surgical techniques, pancreatic resections to treat pancreatic tumors, ampulla tumors, and other pancreatic diseases have increased. Pancreaticoduodenectomy, one type of pancreatic resection, is a complex surgery with the loss of pancreatic integrity and various anastomoses. Complications after pancreaticoduodenectomy such as pancreatic fistulas and anastomosis leakage are common and significantly associated with patient outcomes. Pancreatic fistula is one of the most important postoperative complications; this condition can cause intraperitoneal hemorrhage, septic shock, or even death. An effective way has not yet been found to avoid the occurrence of pancreatic fistula. In most medical centers, the frequency of pancreatic fistula has remained between 9% and 13%. The early detection and routine drainage of anastomotic fistulas, pancreatic fistulas, bleeding, or other intra-abdominal fluid collections after pancreatic resections are considered as important and effective ways to reduce postoperative complications and the mortality rate. However, many recent studies have argued that routine drainage after abdominal operations, including pancreaticoduodenectomies, does not affect the incidence of postoperative complications. Although inserting drains after pancreatic resections continues to be a routine procedure, its necessity remains controversial. This article reviews studies of the advantages and disadvantages of routine drainage after pancreaticoduodenectomy and discusses the necessity of this procedure.

Estimated pancreatic parenchymal remnant volume accurately predicts clinically relevant pancreatic fistula after pancreatoduodenectomy

BACKGROUND

Postoperative pancreatic fistula (POPF) after pancreatoduodenectomy (PD) leads to prolonged hospitalization and potentially fatal complications. We sought to determine whether estimated pancreatic parenchymal remnant volume (EPPRV) on preoperative computed tomography (CT) predicts clinically relevant POPF.

METHODS

This retrospective study included 246 patients who underwent PD between 2008 and 2013. Pancreatic thickness, pancreatic width, and main pancreatic duct (MPD) diameter at the estimated transection line in addition to estimated whole pancreatic remnant volume (EWPRV) were measured on preoperative CT images. MPD volume was subtracted from EWPRV to determine EPPRV. The predictive ability of preoperative CT parameters for POPF was evaluated.

RESULTS

EPPRV was an independent predictor of POPF and had a stronger association with POPF than EWPRV. Receiver operating characteristic curve analysis showed that EPPRV had the greatest area under the curve (0.885) for predicting POPF. EPPRV ≥25.5 cm(3) was the best cutoff value for predicting POPF, with a high negative predictive value (0.934) and low likelihood ratio of a negative result (0.235). Multivariate analysis including the preoperative CT parameters and well-known risk factors for POPF showed that EPPRV ≥25.5 cm(3) had the greatest odds ratio for POPF. EPPRV was correlated with pancreatic juice volume. Patients with EPPRV ≥25.5 cm(3) had a greater drainage fluid amylase concentration and greater duration of drainage tube placement than those with EPPRV <25.5 cm(3).

CONCLUSION

EPPRV from preoperative CT was highly predictive of POPF and may help in development of management for POPF after PD.

A new surgical technique of pancreaticoduodenectomy with splenic artery resection for ductal adenocarcinoma of the pancreatic head and/or body invading splenic artery: impact of the balance between surgical radicality and QOL to avoid total pancreatectomy

For pancreatic ductal adenocarcinoma (PDAC) of the head and/or body invading the splenic artery (SA), we developed a new surgical technique of proximal subtotal pancreatectomy with splenic artery and vein resection, so-called pancreaticoduodenectomy with splenic artery resection (PD-SAR). We retrospectively reviewed a total of 84 patients with curative intent pancreaticoduodenectomy (PD) for PDAC of the head and/or body. These 84 patients were classified into the two groups: conventional PD (n=66) and PD-SAR (n=18). Most patients were treated by preoperative chemoradiotherapy (CRT). Postoperative MDCT clearly demonstrated enhancement of the remnant pancreas at 1 and 6 months in all patients examined. Overall survival rates were very similar between PD and PD-SAR (3-year OS: 23.7% versus 23.1%, P=0.538), despite the fact that the tumor size and the percentages of UICC-T4 determined before treatment were higher in PD-SAR. Total daily insulin dose was significantly higher in PD-SAR than in PD at 1 month, while showing no significant differences between the two groups thereafter. PD-SAR with preoperative CRT seems to be promising surgical strategy for PDAC of head and/or body with invasion of the splenic artery, in regard to the balance between operative radicality and postoperative QOL.

Schematic pancreatic configuration: a risk assessment for postoperative pancreatic fistula after pancreaticoduodenectomy

INTRODUCTION

Postoperative pancreatic fistula (POPF) remains a serious complication after pancreaticoduodenectomy (PD). Preoperative risk assessment of POPF is desirable in careful preparation for operation. The aim of this study was to assess simple and accurate risk factors for clinically relevant POPF based on a schematic understanding of the pancreatic configuration using preoperative multidetector computed tomography.

METHODS

Three hundred and eighteen consecutive patients who underwent PD in the National Cancer Center Hospital East between November 2006 and March 2013 were investigated. Pre-, intra-, and postoperative clinicopathological findings as well as pancreatic configuration data were analyzed for the risk of clinically relevant POPF. POPF was defined according to the International Study Group of Pancreatic Fistula classification. POPF grade A occurred in 52 patients (16.4%), grade B in 84 (26.4%), and grade C in 6 (1.9%).

CONCLUSIONS

Independent risk factors for POPF grade B/C included main pancreatic duct diameter (MPDd) < 2 mm (P = 0.001), parenchymal thickness ≥ 8 mm (P = 0.018), not performing portal vein/superior mesenteric vein resection (P = 0.004), and amylase level of drainage fluid on postoperative day 3 ≥ 375 IU/L (P < 0.001). Pancreatic configuration data including MPDd and parenchymal thickness were good indicators of clinically relevant POPF.

Pancreatic surgery

PURPOSE OF REVIEW

To summarize published research on pancreatic surgery over the past year.

RECENT FINDINGS

A number of studies aiming to reduce the costs associated with pancreatic surgery were reported. Retrospective analyses confirmed previous findings that neither the routine use of pancreatic duct stents decreases the rate of fistula formation nor does placement of a drain at the time of surgery change the morbidity in patients who develop one. Minimally invasive approaches, both laparoscopic and robot-assisted, are being performed more frequently to remove pancreatic cancers. A randomized trial confirmed that reinforcement of stapled closure during distal pancreatectomy reduces the rate of fistula formation. Controversy remains over whether small pancreatic neuroendocrine tumors need to be surgically resected or can be treated nonoperatively. Patients with chronic pancreatitis should be screened thoroughly before being offered surgical treatment; two studies reported preoperative factors that can be used to identify those most likely to experience pain relief.

SUMMARY

Studies published on pancreatic surgery last year focused on a wide-range of topics. The morbidity and mortality of patients undergoing pancreatic surgery continues to improve, and we anticipate that incorporation of these new findings will lead to even better outcomes.