Philippe Ruszniewski

Obesity and Fatty Pancreatic Infiltration Are Risk Factors for Pancreatic Precancerous Lesions (PanIN)

Purpose: The roles of intravisceral and subcutaneous fat are unknown, and the prevalence of precancerous lesions in obese patients was never evaluated. This study aims to assess the frequency and severity of pancreatic intraepithelial neoplasia (PanIN) and to correlate pathologic findings with metabolic abnormalities, type of fat, and fatty pancreatic infiltration. Experimental Design: Normal pancreatic tissue from surgical specimens was analyzed. Fatty infiltration and fibrosis in intra- and extralobular locations and PanIN lesions were assessed. General characteristics were collected: body mass index (BMI), diabetes, and tobacco intake. Liver steatosis and subcutaneous and intravisceral fat were assessed by CT scan (ImageJ software). Results: Of note, 110 patients were included [median age, 53.8 (17–85) years]. Arterial hypertension, diabetes, and tobacco intake were found in 19%, 9%, and 23%, respectively. Median BMI was 24 (16–37; BMI < 25: 45%, 25 ≤ 30: 24%, ≥30: 11%). Overall, PanIN lesions were found in 65% (type I, II, and III PanIN in 62%, 38%, and 1%, respectively). Fibrosis and fatty pancreas (intra- and extralobular locations) were found in 1% and 24% and in 30% and 51%, respectively. A correlation was observed between PanIN lesions and fatty pancreas [extralobular (0.01) and intralobular (<0.0001)], intralobular fibrosis (0.003), high BMI (P = 0.02), and subcutaneous (P = 0.02) and intravisceral fat (P = 0.02). The number of PanIN lesions was correlated with intravisceral fat (r = 0.22, P = 0.04), but not with subcutaneous fat (r = 0.14, P = 0.22). In multivariate analysis, PanIN lesions were associated with intralobular fibrosis [OR, 5.61; 95% confidence interval (CI), 1.18–42.99] and intralobular fat (OR, 17.86; 95% CI, 4.935–88.12). Conclusions: Obesity (especially android obesity) and pancreatic fatty infiltration are risk factors for pancreatic precancerous lesions. Clin Cancer Res; 21(15); 3522–8. ©2015 AACR. See related commentary by Wang et al., p. 3369

Parenchyma-Sparing Resections for Pancreatic Neuroendocrine Tumors

BackgroundParenchyma-sparing pancreatectomy (PSP), including enucleation and central pancreatectomy, has been investigated as an alternative to standard resection for pancreatic endocrine neoplasm, but the benefit/risk of these procedures remains little known.MethodsFrom 1998 to 2010, among 197 patients operated for well-differentiated pancreatic neuroendocrine tumors, 67 underwent PSP (45 enucleations and 22 central pancreatectomies) and 66 standard resections (35 pancreaticoduodenectomies and 31 distal pancreatectomies) for a tumor below 4xa0cm, without synchronous distant metastasis. Groups were compared regarding postoperative morbidity, mortality, long-term pancreatic function, and survival calculated using the Kaplan–Meier method.ResultsTumors operated by PSP had a median size of 15xa0mm, were mainly incidentally diagnosed (nu2009=u200946, 69xa0%), and nonfunctioning (nu2009=u200955, 82xa0%). Overall morbidity rate was higher after PSP than standard resection (SR) (76 vs 58xa0%, pu2009=u20090.0028), including more frequent pancreatic fistulas (69 vs 42xa0%, pu2009=u20090.003). Postoperative diabetes was less frequent following PSP than pancreaticoduodenectomy (5 vs 21xa0%; pu2009=u20090.022) but equivalent to the one observed after distal pancreatectomy (4xa0%, pu2009=u20091). Exocrine insufficiency was significantly less frequent after PSP than SR (3 vs 32xa0%; pu2009<u20090.0001). The overall and recurrence-free 5-year survival after PSP for nonfunctioning tumors was 96 and 98xa0%, respectively.ConclusionIn selected patients, with small and low-grade tumors, PSP are associated with excellent overall and recurrence-free survivals. These procedures are associated with an increased postoperative morbidity but an excellent postoperative pancreatic function. Therefore, they should be considered as a valid therapeutic option in selected well-differentiated pancreatic neuroendocrine tumors.

Anti-tumour effects of lanreotide for pancreatic and intestinal neuroendocrine tumours: the CLARINET open-label extension study

In the CLARINET study, lanreotide Autogel (depot in USA) significantly prolonged progression-free survival (PFS) in patients with metastatic pancreatic/intestinal neuroendocrine tumours (NETs). We report long-term safety and additional efficacy data from the open-label extension (OLE). Patients with metastatic grade 1/2 (Ki-67 ≤10%) non-functioning NET and documented baseline tumour-progression status received lanreotide Autogel 120u200amg (n=101) or placebo (n=103) for 96 weeks or until death/progressive disease (PD) in CLARINET study. Patients with stable disease (SD) at core study end (lanreotide/placebo) or PD (placebo only) continued or switched to lanreotide in the OLE. In total, 88 patients (previously: lanreotide, n=41; placebo, n=47) participated: 38% had pancreatic, 39% midgut and 23% other/unknown primary tumours. Patients continuing lanreotide reported fewer adverse events (AEs) (all and treatment-related) during OLE than core study. Placebo-to-lanreotide switch patients reported similar AE rates in OLE and core studies, except more diarrhoea was considered treatment-related in OLE (overall diarrhoea unchanged). Median lanreotide PFS (core study randomisation to PD in core/OLE; n=101) was 32.8 months (95% CI: 30.9, 68.0). A sensitivity analysis, addressing potential selection bias by assuming that patients with SD on lanreotide in the core study and not entering the OLE (n=13) had PD 24 weeks after last core assessment, found median PFS remaining consistent: 30.8 months (95% CI: 30.0, 31.3). Median time to further PD after placebo-to-lanreotide switch (n=32) was 14.0 months (10.1; not reached). This OLE study suggests long-term treatment with lanreotide Autogel 120u200amg maintained favourable safety/tolerability. CLARINET OLE data also provide new evidence of lanreotide anti-tumour benefits in indolent and progressive pancreatic/intestinal NETs.

An overview of hereditary pancreatitis

Hereditary pancreatitis is a rare cause of chronic pancreatitis. The prevalence was evaluated to 0.3/100000 in Western Countries. Genetic disorders are due to mutations of the PRSS1 gene on the long arm of the chromosome 7, encoding for the cationic trypsinogen. The inheritance pattern is autosomal dominant with an incomplete penetrance (80%). Since 1996, more than 30 mutations were found. The three more common mutations are R122H, N29I and A16V. First symptoms begin since childhood, mainly before 10 years old. Main symptoms are pancreatic pain and acute pancreatitis (>70%). CP morphological changes as pancreatic calcifications are diagnosed at a median age of 22-25 years. Exocrine and endocrine pancreatic insufficiency occurred in 34% and 26% at a median age of 29 and 38 years. No clinical differences exist according to the mutation type. No excess of mortality in hereditary pancreatitis population compared to general population was found, despite a real risk of cancer. The cumulative risks of pancreatic cancer at 50, 60 and, 75 years are 10%, 18.7% and, 53.5%, respectively. The relative risk of cancer increases in smokers and is evaluated to 8.55. Hereditary pancreatitis diagnosis permits to propose an adapted management in expert centres.

Mortality Rate and Risk Factors in Patients With Hereditary Pancreatitis: Uni- and Multidimensional Analyses

OBJECTIVES:Patients with hereditary pancreatitis (HP) bear a high risk of pancreatic adenocarcinoma, but their life expectancy remains unknown. The objective of the study was to assess whether the high risk of cancer decreases survival.METHODS:Inclusion criteria were the presence of a PRSS1 mutation with pancreatic symptoms or chronic pancreatitis in at least two first-degree relatives or three second-degree relatives without another cause. Survival rates were assessed according to risk factors. Excess mortality compared with the general French population was calculated (statistical Esteve model) for two periods (20–50 and 50–70 years), according to several risk factors.RESULTS:The cohort comprised 189 patients. PRSS1 mutations were found in 66%. A total of 19 patients died at the median age of 60. In all, 10 deaths were attributable to HP, including 8 to pancreatic adenocarcinoma. Median overall survival for the whole cohort was 74 years (95% confidence interval (CI): 71–79). The presence of R122H mutation, gender, tobacco consumption in patients older than 18 years, and diabetes mellitus were not associated with differences in survival. Only patients with pancreatic cancer had decreased survival (P=0.008). Excess mortality risk compared with the general population was 0.02% between 20 and 50 years, and 0.61% between 50 and 70 years (NS). Gender, R122H mutation, diabetes, and tobacco use were not associated with excess mortality in these two periods.CONCLUSIONS:Despite their high risk of cancer, HP patients do not have excess mortality risk compared with the general population, irrespective of gender, tobacco use, or diabetes mellitus. These data should be brought to the patients attention.

Immunoglobulin G4 Immunostaining of Gastric, Duodenal, or Colonic Biopsies Is Not Helpful for the Diagnosis of Autoimmune Pancreatitis

BACKGROUND & AIMSnThe aim of this study was to evaluate the specificity of the infiltration of digestive tract mucosa by immunoglobulin (Ig) G4-positive plasma cells in patients with autoimmune pancreatitis (AIP), as compared with normal or inflammatory mucosa.nnnMETHODSnPlasma cell infiltration, CD138 and IgG4 immunostaining of digestive biopsies were compared in 4 groups of patients: AIP type 1 (n = 19); AIP type 2 (n = 4) with inflammatory bowel disease (IBD); IBD without pancreatic disorders (n = 20); and controls (n = 26).nnnRESULTSnWith AIP type 1 versus controls, more plasma cells were present in the gastric mucosa of AIP (P = .02) without difference concerning IgG4+ plasma cells at any biopsy site. With AIP type 1 versus IBD, colonic mucosa was more often abnormal (P = .004), and more CD138 (P = .02) and IgG4 plasma cells (P = .0002) were counted in the colon biopsies of IBD. With AIP type 2 versus IBD, no difference for plasma cell and IgG4 infiltration was found.nnnCONCLUSIONSnIgG4-positive plasma cells are not more numerous in the digestive mucosa of AIP patients than in controls, but they are more abundant in the colon of IBD patients than in AIP patients.

Can pancreatic neuroendocrine tumour biopsy accurately determine pathological characteristics

BACKGROUNDnAssessment of the pathological characteristics of pancreatic neuroendocrine tumours is crucial for appropriate management. We compared preoperative pathological data with surgical specimens for accuracy.nnnMETHODSnSurgical patients with pancreatic neuroendocrine tumours who underwent preoperative endoscopic ultrasound-guided fine needle aspiration of the primary tumour or biopsy of liver metastasis were retrospectively included. Tumour differentiation and the Ki67 proliferation index on biopsies were compared with pancreatic specimens.nnnRESULTSnFifty-seven patients were included. A preoperative biopsy of the primary tumour or of a liver metastasis was obtained in 48 and 9 patients respectively. Tumour differentiation was high in 98%, and poor in 2% on biopsy and high in 100% of surgical specimens. Ki67 index values were 0 (0-19) and 2 (0-15) on biopsy and surgical specimens (p=0.01). Correlation between preoperative and surgical findings was stronger for liver (r=0.62, p=0.001) than for pancreas (r=0.23, p=0.11). Correlation for pancreas varied according to the tumour pattern: solid (r=0.24, p=0.16), mixed (r=0.91, p=0.0036) or cystic (r=0.04, p=0.89). Tumour grade was different between pancreatic biopsies and surgical specimens, for grade 1 (63% vs 37%) and grade 2 (28% vs 72%), p=0.0007.nnnCONCLUSIONSnTumour grade assessment is accurate in biopsies of liver metastases of pancreatic neuroendocrine tumours, while pancreatic fine-needle aspiration biopsies are less accurate.

In situ proteomic analysis by MALDI imaging identifies ubiquitin and thymosin-β4 as markers of malignant intraductal pancreatic mucinous neoplasms

PURPOSEnIntraductal pancreatic mucinous neoplasms (IPMN) are precancerous cystic lesions. The aim was to investigate the in situ IPMN proteome using MALDI (Matrix-Assisted Laser Desorption/Ionisation) imaging and to characterize biomarkers associated with the grade of dysplasia.nnnEXPERIMENTAL DESIGNnFrozen human Branch duct -IPMN sections were selected according to dysplasia and proteomic analyses were performed by MALDI imaging to obtain mass spectra distribution. The most discriminating peaks were identified using tissue extraction and nanoLC-ESI-MS/MS. Identified peaks were validated in independent series of IPMN by immunochemistry on surgical specimens (tissue-microarrays (TMA), nxa0=xa045) and endoscopic ultrasound fine-needle aspiration (EUS FNA) samples (nxa0=xa025).nnnRESULTSnBD-IPMN samples with low (nxa0=xa010) and high (nxa0=xa010) grades of dysplasia were analyzed. Differential spectra of proteins were found in the two groups with significantly different intensities (nxa0=xa015). The two peaks (intense in high grade IPMN) (m/z 8565 and 4747) were characterized as the monomeric ubiquitin (Mascot scorexa0=xa0319.22) and an acetylated fragment of thymosin-β4 (2-42) (Omssa scorexa0=xa01.37 E-9). Validation on TMA and EUS FNA samples confirmed that ubiquitin was overexpressed in high grade dysplasia (pxa0=xa00.04 and pxa0=xa00.0004). Thymosin-β4 expression was confirmed on TMA by immunohistochemistry on high grade IPMN (pxa0=xa00.011).nnnCONCLUSIONnUbiquitin and thymosin-β4 are overexpressed in IPMN with high grade dysplasia. Positive immunochemical staining on EUS-FNA material is a major argument in support of preventive resection.

Nuclear imaging of neuroendocrine tumors with unknown primary: why, when and how?

Neuroendocrine tumors (NETs) with unknown primary (CUP-NET) are associated with a poor prognosis (10-year survival 22xa0%), grade 1 and 2 NETs having a more favorable outcome than grade 3 (also called carcinoma). There is evidence that an effort should be made to localize the primary tumor even in the presence of metastasis because resection of the primary tumor(s) may improve disease-free and overall survival, and because the choice of chemotherapeutic agent depends on the location of the primary tumor. Localization of the tumors remains challenging and often relies on a combination of radiological, endoscopic and functional imaging. The functional imaging protocol for evaluation of these patients has historically relied on somatostatin receptor scintigraphy (SRS). However, the sensitivity and specificity of SRS may be unsatisfactory, especially for NETs of midgut origin. Newer PET radiotracers such as 68Ga-labeled somatostatin analogs (68Ga-DOTA-SSTa) and 18F-DOPA have shown promise. In direct comparisons between 68Ga-DOTA-SSTa PET/CT and 99mTc-HYNIC-octreotide/111In-pentetreotide SPECT(/CT), 68Ga-DOTA-SSTa performed better than other techniques, giving a compelling reason for switching from SPECT/CT to PET/CT imaging. 18F-DOPA performs better than SRS and CT in well-differentiated NETs of the small intestine. For detecting pancreatic NETs, the high background uptake of 18F-DOPA by the normal exocrine pancreas can be somewhat overcome by pretreatment with carbidopa. We have suggested a protocol in which SRS is replaced by one of the two agents (preferably with 68Ga-DOTA-SSTa, alternatively 18F-DOPA) as first-line nuclear tracer for detection of CUP-NET in patients with well-differentiated NETs and 18F-FDG PET/CT may be an additional diagnostic test for poorly differentiated tumors and for prognostication. In the near future, it is expected that patients with CUP-NET will benefit from newly developed PET approaches (radiopharmaceuticals) and intraoperative PET imaging.

Hypoxia pathways and cellular stress activate pancreatic stellate cells: development of an organotypic culture model of thick slices of normal human pancreas.

Pancreatic stellate cells (PSC) are involved in fibrogenesis and oncogenesis by modulating the extracellular matrix. Aim To evaluate the effect of cellular stress on PSC activation using a model of normal human pancreatic tissue slices culture preserving the microenvironment. Methods Thin sections (300μm) of normal human pancreas were cultured under hyperoxia (90% O2) during 72 hours. Viability and morphological analysis were performed at baseline, H24, H48 and H72. Cell differentiation (insulin, trypsin, CA9 and CK7), hypoxia (HIF1-α), apoptosis (caspase-3), proliferation (Ki67), TGF-β expression and PSC activation (smooth muscle actin (SMA), nestin) were assessed using immunostaining, longitudinally. Control experiments were performed under normoxic conditions (21% O2). Results Thirty sections per specimen (n=10) were cultured. Hypoxia pathways were activated by the higher expression of HIF1-α at H48 and H72. Apoptosis was limited with only rare acinar cells expressing of the caspase-3 at 48 and H72 (NS). Morphological analysis showed gradual appearance of acinoductal metaplasia, proven by CK7 expression and ductal phenotype of dedifferentiated acini. Transdifferentiation of PSC was shown by de novo SMA immunochemistry at H24 and H48. Expression of Ki67 index identified significant proliferation of activated PSC (double immunostaining Ki67-SMA) at H48 and H72 (p=0.02). In vitro culture of normal human pancreas thin sections is feasible with optimized cell viability at 72 hours. This model of culture in hyperoxic conditions provides evidences that cellular stress may rapidly induce transactivation of PSC with ducto-acinar metaplasia.