High circulating fibroblast growth factor-21 levels as a screening marker in fatty pancreas patients

Background

The study aimed to detect the serum levels of fibroblast growth factor-21 (FGF-21) in fatty pancreas (FP) patients and to investigate their potential clinical value.

Methods

We screened patients with FP using transabdominal ultrasound. The anthropometric, biochemical and serum levels of FGF-21 were compared between the FP group and the normal control (NC) group. A receiver operating characteristic (ROC) curve was used to evaluate the predictive value of serum FGF-21 for FP patients.

Results

Compared with the NC group, body mass index, fasting blood glucose levels, uric acid levels and cholesterol levels of the FP group were significantly higher, while the high-density lipoprotein level was lower. In addition, levels of serum FGF-21, resistin, leptin and tumor necrosis factor-α were significantly higher than those in the NC group, while the serum adiponectin level was lower. Pearson analysis showed serum FGF-21 levels in FP patients were negatively correlated with leptin. The ROC curve showed the best critical value of the serum FGF-21 level in FP patients was 171 pg/mL (AUC 0.744, P = 0.002, 95% confidence intervals 0.636-0.852).

Conclusion

Serum FGF-21 was closely related to fatty pancreas. Detecting serum FGF-21 levels may help identify the population susceptible to FP.

Fatty Pancreas: Linking Pancreas Pathophysiology to Nonalcoholic Fatty Liver Disease

Currently, scientific interest has focused on fat accumulation outside of subcutaneous adipose tissue. As various imaging modalities are available to quantify fat accumulation in particular organs, fatty pancreas has become an important area of research over the last decade. The pancreas has an essential role in regulating glucose metabolism and insulin secretion by responding to changes in nutrients under various metabolic circumstances. Mounting evidence has revealed that fatty pancreas is linked to impaired β-cell function and affects insulin secretion with metabolic consequences of impaired glucose metabolism, type 2 diabetes, and metabolic syndrome. It has been shown that there is a connection between fatty pancreas and the presence and severity of nonalcoholic fatty liver disease (NAFLD), which has become the predominant cause of chronic liver disease worldwide. Therefore, it is necessary to better understand the pathogenic mechanisms of fat accumulation in the pancreas and its relationship with NAFLD. This review summarizes the epidemiology, diagnosis, risk factors, and metabolic consequences of fatty pancreas and discusses its pathophysiology links to NAFLD.

Pancreatic parenchymal changes seen on endoscopic ultrasound are dynamic in the setting of fatty pancreas: A short-term follow-up study

OBJECTIVES

The impact of fatty pancreas on pancreatic parenchymal changes is unclear. The aim of this study is to assess parenchymal alterations over time in patients with fatty pancreas (FP).

METHODS

This is a retrospective study (2014-2021) of patients with FP identified on endoscopic ultrasound (EUS). Subjects with follow up imaging studies including Computed Tomography (CT) scan, Magnetic Resonance Imaging (MRI), and EUS at least two years after the initial EUS were included.

RESULTS

A total of 39 patients with a mean age of 51.21 ± 12.34 years were included. Mean initial weight was 80.17 ± 17.75 kg. Diabetes, hepatic steatosis, and EPI were present in 15%, 46% and 33% of the patients at baseline, respectively. In 25 patients with available follow up EUS over 2.4 ± 0.76 years, 16% progressed to chronic pancreatitis (CP) and 24% had progressive parenchymal changes without meeting the criteria for CP. One patient progressed from focal to diffuse FP, while one patient had resolution of FP. In multivariate analysis, progressive parenchymal changes on EUS were associated with an increase in weight over time (p-value 0.04), independent of the effects of gender, alcohol, or tobacco.

CONCLUSION

Progressive parenchymal changes were noted in 44%. Our result suggests that FP is a dynamic process with the possibility of progression or regression over time.

Uniting epidemiology and experimental models: pancreatic steatosis and pancreatic cancer

Research from epidemiologic studies and experimental animal models provide insights into the role of pancreatic steatosis in the development of pancreatic cancer. Epidemiologic data demonstrate that pancreatic steatosis is widely prevalent and significantly associated with both development and progression of pancreatic cancer. By focusing on current experimental models, this review elucidates potential cellular mechanisms underlying not only the pathophysiology of pancreatic steatosis itself, but also the pathogenesis behind pancreatic steatosis's role in changing the tumour microenvironment and accelerating the development of pancreatic cancer. This review further explores the impact of bariatric surgery on pancreatic steatosis and pancreatic cancer. Synthesizing knowledge from both epidemiologic studies and experimental animal models, this review identifies gaps in current knowledge regarding pancreatic steatosis and its role in carcinogenesis and proposes future research directions to elucidate the possible mechanisms underlying other obesity-associated cancers.

Impact of pancreatic fat on the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis

BACKGROUND AND STUDY AIMS

Fatty pancreas is a potential risk factor for acute pancreatitis; however, whether it is also a risk factor for post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) has not been evaluated. We aimed to determine the impact of fatty pancreas on the development of PEP.

METHODS

We analyzed the data of patients who underwent abdominal computed tomography (CT) scan and sequential therapeutic endoscopic retrograde cholangiopancreatography (ERCP). Fatty change in the pancreas was evaluated based on pancreatic attenuation of unenhanced image on CT scan. The risk of fatty pancreas for the development of PEP was evaluated using a logistic regression model.

RESULTS

Of a total of 858 patients included in the study, 354 (41.3%) had fatty pancreas, while 504 (58.7%) did not have fatty pancreas. PEP developed in 28 patients (7.9%) in the fatty pancreas group and in 13 patients (2.6%) in the no fatty pancreas group. Fatty pancreas was significantly associated with the development of PEP (odds ratio [OR] [95% confidence interval [CI]] 2.38 [1.16-4.87]). A history of acute pancreatitis, female sex, difficult cannulation, and endoscopic papillary balloon dilation were also risk factors for the development of PEP. The risk for moderate-to-severe PEP development tended to be higher in the fatty pancreas group than in the no fatty pancreas group (OR [95% CI] 5.61 [0.63-49.62]).

CONCLUSIONS

Fatty pancreas is a significant risk factor for the development of PEP. Clinicians need to be aware of the risk of fatty pancreas for the development of PEP prior to performing ERCP.

Hyperechoic pancreas on ultrasonography: an analysis of its severity and clinical implications

Purpose

This study investigated risk factors for hyperechoic pancreas (HP) on ultrasonography (US) according to HP severity.

Methods

Between December 2008 and February 2014, 1,459 subjects who underwent abdominal US as part of health examinations were retrospectively included. Two radiologists assessed and categorized the severity of HP as normal, mild, moderate, and severe. Subjects were allocated to two groups as follows: fatty pancreas 1 (FP1; mild to severe HP) and fatty pancreas 2 (FP2; moderate to severe HP). Clinico-metabolic parameters such as the body mass index and blood test profile of subjects with normoglycemia and prediabetes/diabetes were compared (normal vs. FP1; normal or mild HP vs. FP2). Logistic regression analysis was used to evaluate the associations between HP, nonalcoholic fatty liver disease (NAFLD), and diabetes/prediabetes with adjustment for clinico-metabolic parameters.

Results

Of the 1,459 subjects, 71.2% and 40.4% showed HP and NAFLD on US, respectively. Normoglycemia and prediabetes/diabetes were present in 74.3% and 25.7% of subjects, respectively. Univariable analysis revealed that all the clinico-metabolic parameters were significantly associated with HP (all P<0.05). In the adjusted multivariable analysis, prediabetes/diabetes, NAFLD, age, and body mass index were significantly associated with HP with the FP1 and FP2 criteria. The independent factor with the strongest association with HP was NAFLD using the FP1 criterion (odds ratio [OR], 7.93; P<0.001) and prediabetes/diabetes using the FP2 criterion (OR, 6.96; P<0.001).

Conclusion

NAFLD and prediabetes/diabetes were associated with US-diagnosed HP. Moderate to severe HP was a better predictor of prediabetes/diabetes, suggesting that evaluating HP severity may be useful in clinical practice.

Pancreatic steatosis on computed tomography is an early imaging feature of pre-diagnostic pancreatic cancer: A preliminary study in overweight patients

BACKGROUND

The prevalence of pancreatic ductal adenocarcinoma (PDAC) is on the rise, driven by factors such as aging and an increasing prevalence of obesity and diabetes mellitus. To improve the poor survival rate of PDAC, early detection is vital. Recently, pancreatic steatosis has gained novel interest as a risk factor for PDAC. This study aimed to investigate if pancreatic steatosis on computed tomography (CT) is an early imaging feature in patients with pre-diagnostic PDAC.

METHODS

A retrospective case-control study was performed. Patients diagnosed with PDAC (2010-2016) were reviewed for abdominal non-contrast CT-imaging 1 month-3 years prior to their diagnosis. Cases were matched 1:4 with controls based on age, gender and imaging date. Unenhanced CT-images were evaluated for pancreatic steatosis (pancreas-to-spleen ratio in Hounsfield Units <0.70) by a blinded radiologist and results were compared between cases and controls.

RESULTS

In total, 32 cases and 117 controls were included in the study with a comparable BMI (29.6 and 29.2 respectively, p = 0.723). Pancreatic steatosis was present in 71.9% of cases compared to 45.3% of controls (Odds ratio (OR) 3.09(1.32-7.24), p = 0.009). Adjusted for BMI and diabetes mellitus, pancreatic steatosis on CT remained a significant independent risk factor for PDAC (Adjusted OR 2.70(1.14-6.58), p = 0.037).

CONCLUSION

Pancreatic steatosis measured on CT is independently associated with PDAC up to three years before the clinical diagnosis in overweight patients. If these data are confirmed, this novel imaging feature may be used to identify high-risk individuals and to stratify the risk of PDAC in individuals that already undergo PDAC screening.

Severity of hyperechoic pancreas on ultrasonography as a risk factor for glycemic progression

Purpose

The aim of this study was to evaluate the association between the severity of hyperechoic pancreas (HP) on ultrasonography (US) and glycemic progression.

Methods

In total, 1,386 participants who underwent abdominal US as part of health examinations between December 2008 and May 2014 were included in this retrospective study. We classified pancreatic echogenicity on a 4-point scale, and compared it using two distinct criteria: fatty pancreas (FP) 1 criterion (normal vs. ≥mild HP) and FP2 criterion (normal/mild HP vs. ≥moderate HP). According to the presence of nonalcoholic fatty liver disease (NAFLD), participants were subdivided into four groups: non-NAFLD and non-HP, isolated NAFLD, isolated HP, and HP with NAFLD. Glycemic progression was defined as progression from normoglycemia to prediabetes or diabetes or progression from prediabetes to diabetes.

Results

During the follow-up (median, 5.9 years), 262 of the 1,386 participants developed glycemic progression. Using FP2, the probability of glycemic progression across the four subgroups showed cumulative aggravation for NAFLD and HP (all P<0.05). Isolated HP showed a higher probability of glycemic progression than isolated NAFLD according to FP2 (P<0.001). The highest probability of glycemic progression was observed in patients with both NAFLD and HP (P<0.001). The hazard ratio for glycemic progression increased with the severity of HP.

Conclusion

Increasing severity of HP on US was found to be significantly correlated with glycemic progression. Moreover, isolated HP of moderate or greater severity predicted glycemic progression independent of NAFLD.

Longitudinal association of fatty pancreas with the incidence of type-2 diabetes in lean individuals: a 6-year computed tomography-based cohort study

BACKGROUND

Only a few studies have longitudinally evaluated whether fatty pancreas increases the risk of type-2 diabetes (T2D), and their results were inconsistent. Fatty pancreas is closely linked to overweight and obesity, but previous studies did not exclude overweight or obese individuals. Therefore, in this cohort study, we investigated the association between fatty pancreas and T2D incidence in lean individuals.

METHODS

Between 2008 and 2013, 1478 nondiabetic lean individuals (i.e. body-mass index < 25 kg/m²) underwent health examinations including computed tomography (CT) and were followed for a median of 6.19 years. Fatty pancreas was evaluated by a histologically-validated method using pancreas attenuation (Hounsfield units [HU]) on CT at baseline; lower pancreas attenuation indicates more pancreatic fat. To detect incident T2D, we used fasting plasma glucose, HbA1c, and self-reports of prescribed anti-diabetes medications. Odds ratios (OR) for the association between pancreas attenuation and incident T2D were estimated using logistic regression models adjusted for likely confounders.

RESULTS

T2D occurred in 61 participants (4.13%) during the follow-up period. Lower pancreas attenuation (i.e. more pancreatic fat) at baseline was associated with incident T2D (unadjusted OR per 10 HU lower attenuation: 1.56 [95% CI 1.28-1.91], p < 0.001). The multivariable-adjusted analysis revealed a similar association (adjusted OR per 10 HU lower attenuation: 1.32 [95% CI 1.06-1.63], p = 0.012).

CONCLUSIONS

T2D was likely to develop in lean individuals with the fatty pancreas. Among people who are neither obese nor overweight, the fatty pancreas can be used to define a group at high risk for T2D.

Pancreatic Fat Infiltration Is Associated with a Higher Risk of Pancreatic Ductal Adenocarcinoma

Background

Pancreatic ductal adenocarcinoma (PDAC) has a poor survival rate, partly due to delayed diagnosis. Identifying high-risk individuals could lead to early detection and improve survival. A number of risk factors such as alcohol consumption and metabolic syndrome are associated with fatty infiltration of the pancreas. Experimental models show that a fatty pancreas promotes tissue inflammation and fibrosis, which could promote PDAC.

Methods

We conducted a case-control study in a single-university tertiary hospital. Sixty-eight PDAC cases with recent non-contrast computed tomography (CT) and 235 controls were studied. The controls had no history of malignancy and underwent CT colonography for cancer screening in the same period. Pancreatic fat was estimated by calculating pancreatic (P) attenuation, corrected to splenic (S) attenuation, measured in three 1.0-cm² regions of the pancreas. The P.S100 value calculated was used to estimate fatty infiltration of the pancreas (FIP), with a lower P.S100 representing a higher FIP.

Results

The PDAC patients had a lower BMI and a higher rate of type 2 diabetes mellitus. The P.S100 was lower in cases than in controls (86.452 vs. 92.414, p = 4.016e-06), suggesting that FIP is higher with PDAC. The risk of developing PDAC steadily increased significantly for the quartiles with a higher FIP compared to the low FIP quartile. No correlation between BMI and FIP (r = -0.1031179; 95% confidence interval [CI] -0.22267106 to 0.01949092) was found. Adjusting for confounders (age, sex, BMI, and DM), the risk of developing PDAC according to the FIP was estimated to be 3.75 (95% CI 1.9234408-7.993337; p = 0.000171). FIP was stable before and after the diagnosis of PDAC in 9 cases with prior CT scans when no pancreatic tumor was identifiable.

Conclusion

Fatty pancreas is associated with an increased risk of pancreatic cancer. Once confirmed in larger-scale studies, these findings could help to identify at-risk individuals, particularly in high-risk groups such as chronic alcohol consumers.

Circulating levels of lipocalin-2 are associated with fatty pancreas but not fatty liver

Lipocalin-2 (LCN-2), a peptide with diverse expression pattern, has been identified as a biomarker of various diseases as well as a factor contributing to inflammatory responses associated with excess adiposity and ensuing metabolic disorders. Although the inter-relationship between LCN-2 and excess adiposity is increasingly recognized, little is known about the inter-relationship between LCN-2 and ectopic fat deposition. The present study aimed to investigate the associations between LCN-2 and fatty pancreas as well as fatty liver. In addition, the associations between LCN-2 and pro-inflammatory cytokines were studied. Magnetic resonance imaging was used to quantify intra-pancreatic fat deposition and visceral-to-subcutaneous fat volume ratio whereas magnetic resonance spectroscopy was used to quantify liver fat deposition. Fasting venous blood was analyzed for LCN-2, C-C motif chemokine ligand 2, interleukin-6, leptin, tumor necrosis factor-α, glycated hemoglobin, glucose, and insulin. Binary logistic regression and linear regression analyses were conducted. Three statistical models were built to adjust for demographics, comorbidities, levels of glycated hemoglobin, insulin resistance, and abdominal fat distribution. A total of 79 individuals were studied, of whom 20 had fatty pancreas, 14 had fatty liver, and 4 had both. Lipocalin-2 was significantly associated with fatty pancreas in all the adjusted models (p = 0.014 in the most adjusted model) but was not significantly associated with fatty liver in any of the studied models. Lipocalin-2 was significantly associated with interleukin-6 and tumor necrosis factor-α, in both the unadjusted and adjusted models. Leptin and C-C motif chemokine ligand 2 were not significantly associated with LCN-2 in any of the studied models. These findings suggest that LCN-2 is a potential biomarker of fatty pancreas, independent of abdominal fat distribution, insulin resistance, and other covariates. The role of LCN-2 in intra-pancreatic fat deposition and related low-grade inflammation warrants further investigations.

Hepatic and pancreatic fat as imaging biomarkers of metabolic syndrome

OBJECTIVE

To objectively evaluate hepatic and pancreatic involvement in metabolic syndrome through magnetic resonance imaging (MRI) biomarkers.

MATERIAL AND METHODS

From an initial retrospective sample of 407 patients diagnosed with metabolic syndrome studied by MRI in a single center during a 2-year period, 154 were excluded because of a lack of clinical and/or laboratory data, pancreatic abnormalities, or inadequate quality of MRI studies. To measure hepatic and pancreatic fat, we used chemical shift imaging (in-phase and out-of-phase), measuring the fat fraction (%) in regions of interest in the pancreas and liver. Associations between the fat fraction and selected clinical and laboratory variables were assessed with beta regression models.

RESULTS

In the end, 253 patients were included. The hepatic fat fraction was 4.9% and the pancreatic fat fraction was 7.9%. We found no significant associations between the hepatic fat fraction and any of the clinical or laboratory variables. However, the pancreatic fat fraction was positively associated with age (OR=1.025, p<0.001) and baseline glucose (OR=1.005, p<0.001). Patients with diabetes had higher values of pancreatic fat fraction (OR=2.64, p=0.038). Pancreatic fat fraction and hepatic fat fraction were positively associated (OR=69.44, p<0.001).

CONCLUSIONS

Pancreatic steatosis can be considered a marker of metabolic syndrome and diabetes. Quantitative MRI enables the diagnosis and grading of fatty pancreas through simple chemical shift techniques.

Evaluation of fatty pancreas by proton density fat fraction using 3-T magnetic resonance imaging and its association with pancreatic cancer

PURPOSE

To evaluate whether pancreatic magnetic resonance imaging-proton density fat fraction (MRI-PDFF) correlates with histological pancreatic fat fraction and its possible usefulness as a biomarker of pancreatic cancer compared with pancreatic index (PI) using computed tomography (CT number of the pancreas divided by that of the spleen).

METHOD

We included 55 consecutive patients (24 with pancreatic cancer and 31 controls; median age, 72 years) who preoperatively underwent MRI-PDFF using IDEAL-IQ and unenhanced CT and did not receive preoperative therapy. Histologic pancreatic fat fraction was measured in non-tumorous pancreatic tissues at the resection stump. A board-certified radiologist evaluated MRI-PDFF and PI. Correlations were evaluated among MRI-PDFF, PI, and histologic pancreatic fat fraction; the usefulness of MRI-PDFF as a predictor of pancreatic cancer was assessed.

RESULTS

Histologic pancreatic fat fraction significantly correlated with MRI-PDFF and PI (r = 0.802 and -0.534, respectively; P < 0.01). The absolute correlation coefficient was significantly higher for MRI-PDFF than for PI (P < 0.01). Compared with the control group, the pancreatic cancer group had higher MRI-PDFF and histologic pancreatic fat fraction (P < 0.01) but lower PI (P < 0.01). In multivariate analysis, MRI-PDFF was found to be the sole independent risk factor for pancreatic cancer (odds ratio: 1.19; P < 0.01).

CONCLUSIONS

Pancreatic fat, which was associated with pancreatic cancer, could be quantified by MRI-PDFF measurement; therefore, MRI-PDFF should be considered as a promising and superior imaging biomarker for estimating the probability of pancreatic cancer than PI.

Association between hyperechogenic pancreas and pancreatic ductal adenocarcinoma concomitant with intraductal papillary mucinous neoplasms

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) may independently occur in the pancreas separate from an intraductal papillary mucinous neoplasm (IPMN). Therefore, identifying the characteristics of patients with IPMN who will likely develop PDAC is clinically important. Although a recent study found that fatty pancreas correlated with PDAC, no reports have examined this matter in patients with IPMN. A previous study showed that fatty pancreas increased the echogenicity; hence, this study aimed to investigate the association between hyperechogenic pancreas and PDAC in patients with IPMN.

METHODS

We retrospectively collected data of patients with IPMN who underwent endoscopic ultrasonography (EUS) between January 2012 and November 2018. A case-control analysis was performed between patients with IPMN concomitant with PDAC (cases) and those without PDAC (controls). We identified controls by matching age and sex with cases. The echogenicity of the pancreas was determined using EUS by comparing it with the left kidney or spleen. Echogenicity was determined using transabdominal ultrasonography by comparison with that of the liver when it was difficult to determine using EUS.

RESULTS

Among 400 patients with IPMN, 23 cases and 92 controls were identified. The proportion of patients with hyperechogenic pancreas was significantly greater in cases than in controls (91.3% vs. 65.2%, P = 0.02). Multivariate analysis, including family history of pancreatic cancer, multifocal cysts, and hyperechogenic pancreas, showed that hyperechogenic pancreas was correlated with PDAC concomitant with IPMN (odds ratio = 7.07; 95% confidence interval = 1.48-33.80; P = 0.01).

CONCLUSION

Our analysis demonstrated that hyperechogenic pancreas was associated with concomitant PDAC in patients with IPMN.

What role do fat cells play in pancreatic tissue?

Background

It is now generally accepted that obesity is a major risk factor for type 2 diabetes mellitus (T2DM). Hepatic steatosis in particular, as well as visceral and ectopic fat accumulation within tissues, is associated with the development of the disease. We recently presented the first study on isolated human pancreatic adipocytes and their interaction with islets [Gerst, F., Wagner, R., Kaiser, G., Panse, M., Heni, M., Machann, J., et al., 2017. Metabolic crosstalk between fatty pancreas and fatty liver: effects on local inflammation and insulin secretion. Diabetologia 60(11):2240–2251.]. The results indicate that the function of adipocytes depends on the overall metabolic status in humans which, in turn, differentially affects islet hormone release.

Scope of Review

This review summarizes former and recent studies on factors derived from adipocytes and their effects on insulin-secreting β-cells, with particular emphasis on the human pancreas. The adipocyte secretome is discussed with a special focus on its influence on insulin secretion, β-cell survival and apoptotic β-cell death.

Major Conclusions

Human pancreatic adipocytes store lipids and release adipokines, metabolites, and pro-inflammatory molecules in response to the overall metabolic, humoral, and neuronal status. The differentially regulated adipocyte secretome impacts on endocrine function, i.e., insulin secretion, β-cell survival and death which interferes with glycemic control. This review attempts to explain why the extent of pancreatic steatosis is associated with reduced insulin secretion in some studies but not in others.

Research status of fatty pancreas

Fatty pancreas is a newly proposed condition which is characterized by fat deposition and steatosis in the pancreas followed by outcome of pancreatic and metabolic complications. It has been found to be correlated with many metabolic disorders and a variety of diseases. Fatty pancreas has been associated with obesity, non-alcoholic fatty liver disease, metabolic syndrome, type 2 diabetes mellitus, acute and chronic pancreatitis, and even pancreatic carcinoma. Therefore, fatty pancreas might not only be an early marker of glucose or lipid metabolism disorders or metabolic syndrome, but also be a predictor of poor outcome of pancreatic related diseases. At present, imaging examination is the main diagnostic method. However, there is currently still a lack of a unified terminology, diagnostic criteria, treatment consensus, and guidelines due to very limited knowledge on this condition. Here we discuss the pathophysiology, pathogenesis, clinical implications, diagnosis, and treatment of fatty pancreas, with an aim to improve the early intervention, treatment, and prognosis prediction of fatty pancreas related metabolic disorders.

The Clinical Implications of Fatty Pancreas: A Concise Review

Fatty pancreas is a newly recognized condition which is poorly investigated until today as compared to nonalcoholic fatty liver disease. It is characterized by pancreatic fat accumulation and subsequent development of pancreatic and metabolic complications. Association of fatty pancreas have been described with type 2 diabetes mellitus, acute and chronic pancreatitis and even pancreatic carcinoma. In this review article, we provide an update on clinical implications, pathogenesis, diagnosis, treatment and outcomes.

In Patients with a Soft Pancreas, a Thick Parenchyma, a Small Duct, and Fatty Infiltration Are Significant Risks for Pancreatic Fistula After Pancreaticoduodenectomy

BACKGROUND

This study sought to characterize soft and hard pancreatic textures radiologically and histologically, and to identify specific risks in a soft pancreas associated with postoperative pancreatic fistula (POPF) formation after pancreaticoduodenectomy (PD).

METHODS

Consecutive 145 patients who underwent PD at a single institution between January 2010 and May 2013 were studied. Pancreatic consistency was intraoperatively judged as soft or hard. Pancreatic configuration was assessed using preoperative CT. Histologic components of the pancreatic stump were evaluated using a morphometric analysis. Clinicopathologic parameters were then analyzed for the risk of clinically relevant POPF.

RESULTS

Compared with patients with a hard pancreas (n = 66), those with a soft pancreas (n = 79) had a smaller main pancreatic duct (MPD) diameter and a larger parenchymal thickness on CT, had a smaller fibrosis ratio and a larger lobular ratio histologically, and developed clinically relevant POPF more frequently (P < 0.001 for all). In patients with a soft pancreas, an MPD diameter <2 mm, a parenchymal thickness ≥10 mm, a lobular ratio <75%, and a fat ratio ≥20% were independently associated with clinically relevant POPF (P < 0.010 for all).

CONCLUSION

In patients with a soft pancreas, a thick parenchyma, a small MPD, and fatty infiltration were strongly associated with clinically relevant POPF after PD.

Risk Factor of Pancreatic Fistula after Radical Gastrectomy from the Viewpoint of Fatty Pancreas

BACKGROUND

We suspected that fatty pancreas, accompanied with metabolic syndrome, may be associated with the incidence of postoperative pancreatic fistula (POPF) after radial gastrectomy.

METHODS

Between February 2012 and March 2014, we reviewed consecutive 79 gastric cancer patients who underwent radical gastrectomy. To quantify the degree of fatty infiltration to pancreas by preoperative contrast-enhanced CT, we measured ratios and differences between pancreatic and splenic attenuation values (P/S and P-S, respectively). The optimal cut-off values of P/S and P-S for predicting POPF were determined using the receiver operating characteristic (ROC) curve analysis. Risk factors for POPF of International Study Group on Pancreatic Fistula grade B or higher were examined using univariate and multivariate analyses.

RESULTS

POPF occurred in 6 patients (7.6%). ROC curve analyses revealed that the most optimal predictive values of P/S and P-S were 0.74 and -28.8, respectively. Univariate analysis demonstrated that high visceral fat area (p = 0.037), low P/S (p = 0.013), and low P-S (p = 0.006) were significant risk factors of POPF. Multivariate analysis demonstrated that low P/S (OR 10.2 [p = 0.046]) and low P-S (OR 13.2 [p = 0.023]) were significant risk factors of POPF.

CONCLUSION

Fatty pancreas is a risk factor of POPF after radical gastrectomy.

Exploring the metabolic syndrome: Nonalcoholic fatty pancreas disease

After the first description of fatty pancreas in 1933, the effects of pancreatic steatosis have been poorly investigated, compared with that of the liver. However, the interest of research is increasing. Fat accumulation, associated with obesity and the metabolic syndrome (MetS), has been defined as “fatty infiltration” or “nonalcoholic fatty pancreas disease” (NAFPD). The term “fatty replacement” describes a distinct phenomenon characterized by death of acinar cells and replacement by adipose tissue. Risk factors for developing NAFPD include obesity, increasing age, male sex, hypertension, dyslipidemia, alcohol and hyperferritinemia. Increasing evidence support the role of pancreatic fat in the development of type 2 diabetes mellitus, MetS, atherosclerosis, severe acute pancreatitis and even pancreatic cancer. Evidence exists that fatty pancreas could be used as the initial indicator of “ectopic fat deposition”, which is a key element of nonalcoholic fatty liver disease and/or MetS. Moreover, in patients with fatty pancreas, pancreaticoduodenectomy is associated with an increased risk of intraoperative blood loss and post-operative pancreatic fistula.

Maternal obesity alters endoplasmic reticulum homeostasis in offspring pancreas

The prevalence of non-alcoholic fatty pancreas disease (NAFPD) is increasing in parallel with obesity rates. Stress-related alterations in endoplasmic reticulum (ER), such as the unfolded protein response (UPR), are associated with obesity. The aim of this study was to investigate ER imbalance in the pancreas of a mice model of adult and perinatal diet-induced obesity. Twenty female C57BL/6J mice were assigned to control (Con) or obesogenic (Ob) diets prior to and during pregnancy and lactation. Their offspring were weaned onto Con or Ob diets up to 6 months post-partum. Then, after sacrifice, plasma biochemical analyses, gene expression, and protein concentrations were measured in pancreata. Offspring of Ob-fed mice had significantly increased body weight (p < 0.001) and plasma leptin (p < 0.001) and decreased insulin (p < 0.01) levels. Maternal obesogenic diet decreased the total and phosphorylated Eif2α and increased spliced X-box binding protein 1 (XBP1). Pancreatic gene expression of downstream regulators of UPR (EDEM, homocysteine-responsive endoplasmic reticulum-resident (HERP), activating transcription factor 4 (ATF4), and C/EBP homologous protein (CHOP)) and autophagy-related proteins (LC3BI/LC3BII) were differently disrupted by obesogenic feeding in both mothers and offspring (from p < 0.1 to p < 0.001). Maternal obesity and Ob feeding in their offspring alter UPR in NAFPD, with involvement of proapoptotic and autophagy-related markers. Upstream and downstream regulators of PERK, IRE1α, and ATF6 pathways were affected differently following the obesogenic insults.

The effect of fatty pancreas on serum glucose parameters in patients with nonalcoholic steatohepatitis

OBJECTIVE

Fatty pancreas (FP) is related to obesity, and may have some clinical implications on glucose metabolism. The frequency and importance of FP in patients with nonalcoholic steatohepatitis (NASH) are not clear. This study aimed to investigate: the frequency of FP in patients with NASH, and its effects on serum glucose parameters.

METHODS

FP was detected and graded by transabdominal ultrasonography (USG) in patients with biopsy-proven NASH and healthy controls. Body Mass Index and waist circumference were recorded, and serum lipids, fasting serum glucose, HbA1c, OGTT 2-h, insulin level, insulin resistance, type 2 diabetes mellitus (DM) and prediabetes rates were detected.

RESULTS

Eighty-four subjects with NASH and 35 healthy controls were enrolled in the study. There was no FP in 41 (48.8%) of the NASH patients according to the study criteria. Forty-three of the NASH patients and 5 of the controls had different grades of fat in their pancreas (51.2% vs. 14%, p=0.001). The HbA1c and OGTT 2-h results were significantly higher in NASH patients with FP compared to those without FP (p=0.003 and p=0.018). The rates of both prediabetes and DM were also found to be significantly increased in NASH patients with FP (p=0.004). The mean waist circumference was higher in patients with FP (p=0.027). Grade of FP by USG showed no effect on study parameters in subgroup analysis.

CONCLUSION

FP is common in patients with NASH and increases the rate of prediabetes and DM. The coexistence of both NASH and FP has a further impact on glucose metabolism and DM frequency.

Pancreatic hyperechogenicity on endoscopic ultrasound examination

There is an ongoing discussion on how to diagnose a hyperechogenic pancreas and what is the clinical significance of diffusely hyperechogenic pancreas. Computerized tomography and magnetic resonance imaging are the more appropriate methods to diagnose pancreatic hyperechogenicity when compared with transcutaneous or endoscopic ultrasound examination. More importantly, pancreatic hyperechogenicity may not be a certain indicator of pancreatic fat infiltration. Even if it is true, we do not know the clinical significances of pancreatic fat accumulation. Some suggested that excess fat in the pancreas is associated with chronic pancreatitis. However, several histological studies on human alcoholic chronic pancreatitis did not prove the presence of fatty pancreas in such cases. Thus, except for aging, it is very rare to have truly steatotic pancreas in the absence of certain human diseases.

Clinical implications of fatty pancreas: Correlations between fatty pancreas and metabolic syndrome

AIM: To investigate the clinical implications of lipid deposition in the pancreas (fatty pancreas).

METHODS: The subjects of this study were 293 patients who had undergone abdominal computed tomography (CT) and sonography. Fatty pancreas was diagnosed by sonographic findings and subdivided into mild, moderate, and severe fatty pancreas groups comparing to the retroperitoneal fat echogenicity.

RESULTS: Fatty pancreas was associated with higher levels for visceral fat, waist circumference, aspartate aminotransferase (AST), alanine aminotransferase (ALT), total cholesterol, triglyceride, high density lipoprotein, free fatty acid, γ-GTP, insulin, and the homeostasis model assessment of insulin resistance (HOMA-IR) than the control group (P < 0.05). HOMA-IR, visceral fat, triglyceride, and ALT also tended to increase with the degree of fat deposition in the pancreas on sonography. In a multivariate logistic regression analysis, HOMA-IR, visceral fat, and ALT level were independently related to fatty pancreas after adjustment for age, body mass index, and lipid profile. The incidence of metabolic syndrome in the fatty pancreas group was significantly higher than in the control group, and the numbers of metabolic syndrome parameters were significantly higher in the fatty pancreas group (P < 0.05).

CONCLUSION: Sonographic fatty pancrease showed higher insulin resistance, visceral fat area, triglyceride, and ALT levels than normal pancreases. Fatty pancreas also showed a strong correlation with metabolic syndrome.