Extranodal extension of lymph node metastasis is a marker of poor prognosis in oesophageal cancer: a systematic review with meta-analysis

The extranodal extension (ENE) of nodal metastasis is the extension of neoplastic cells through the nodal capsule into the perinodal adipose tissue. This histological feature has recently been indicated as an important prognostic factor in different types of malignancies; in this manuscript, we aim at defining its role in the prognosis of oesophageal cancer with the tool of meta-analysis. Two independent authors searched SCOPUS and PubMed until 31 August 2015 without language restrictions. The studies with available data about prognostic parameters in subjects with oesophageal cancer, comparing patients with the presence of ENE (ENE+) versus only intranodal extension (ENE-), were considered as eligible. Data were summarised using risk ratios (RRs) for number of deaths/recurrences and HRs together with 95% CIs for time-dependent risk related to ENE+, adjusted for potential confounders. Fourteen studies were selected; they followed-up 1437 patients with oesophageal cancer for a median follow-up of 39.4 months. The presence of ENE was associated with a significantly increased risk of all-cause mortality (RR=1.33; 95% CI 1.18 to 1.50, p<0.0001, I²=49%; HR=2.72, 95% CI 2.03 to 3.64, p<0.0001, I²=0%), cancer-specific mortality (RR=1.35; 95% CI 1.14 to 1.59, p=0.001, I²=57%; HR=1.97, 95% CI 1.41 to 2.75, p<0.0001, I²=41%) and of risk of recurrence (RR=1.50, 95% CI 1.20 to 1.88, p<0.0001, I²=9%; HR=2.27, 95% CI 1.72 to 2.90, p<0.0001, I²=0%). On the basis of these results, in oesophageal cancer, ENE should be considered from the gross sampling to the pathology report, and in future oncological staging system.

Long-term outcomes and prognostic factors in neuroendocrine carcinomas of the pancreas: Morphology matters

BACKGROUND

Limited data are available for pancreatic neuroendocrine carcinomas (NEC) defined by 2010 World Health Organization (WHO) criteria (mitotic count >20 mitoses/10 high-power fields and/or a Ki67 index of >20%), because most studies encompass heterogeneous cohorts of extrapulmonary/gastrointestinal NEC. Our aim was to evaluate the clinicopathologic characteristics, treatment, and prognosis of patients with pancreatic NEC defined by the 2010 WHO criteria.

METHODS

We conducted a retrospective analysis of 59 patients with a histologic diagnosis of NEC between 1990 and 2012. All cases were re-reviewed and classified according to the WHO 2010 classification and the WHO 2000 criteria.

RESULTS

All patients had stage III pancreatic NEC (n = 34; 58%) or IV pancreatic NEC (n = 25; 43%). Overall, 49 (83%) had poorly differentiated (PD) and 10 (17%) had a well-differentiated (WD) morphology. Fifteen patients (26%) were operated with curative intent (R0/R1), and 8 (14%) were R2 resections. Median disease-specific survival (DSS) for the entire cohort was 14 months. Median DSS did not differ between patient not undergoing resection and those undergoing R2 resection (10 vs 12 months; P > .46), but DSS was greater for patients who underwent R0/R1 resection compared with those with no resection/R2 resection (35 vs 11 months; P < .005). WD morphologic NEC had a greater survival than PD ones (43 vs 12 months; P = .004). Performance status, R2 resection/no resection, PD morphologic NEC, and no medical treatment were independent predictors of poor survival.

CONCLUSION

Pancreatic NEC constitute a heterogeneous group of tumors. Although NEC is an aggressive disease, curative resection in localized disease is associated with improved survival. Morphologic WD pancreatic NEC represents a subgroup with what seems to be a markedly improved survival. Within the NEC category, tumor treatment should be individualized considering tumor morphology as well as the other 2010 WHO criteria.

Identification of novel mutations in hemochromatosis genes by targeted next generation sequencing in Italian patients with unexplained iron overload

Hereditary hemochromatosis, one of the commonest genetic disorder in Caucasians, is mainly associated to homozygosity for the C282Y mutation in the HFE gene, which is highly prevalent (allele frequency up to near 10% in Northern Europe) and easily detectable through a widely available "first level" molecular test. However, in certain geographical regions like the Mediterranean area, up to 30% of patients with a HH phenotype has a negative or non-diagnostic (i.e. simple heterozygosity) test, because of a known heterogeneity involving at least four other genes (HAMP, HJV, TFR2, and SLC40A1). Mutations in such genes are generally rare/private, making the diagnosis of atypical HH essentially a matter of exclusion in clinical practice (from here the term of "non-HFE" HH), unless cumbersome traditional sequencing is applied. We developed a Next Generation Sequencing (NGS)-based test targeting the five HH genes, and applied it to patients with clinically relevant iron overload (IO) and a non-diagnostic first level genetic test. We identified several mutations, some of which were novel (i.e. HFE W163X, HAMP R59X, and TFR2 D555N) and allowed molecular reclassification of "non-HFE" HH clinical diagnosis, particularly in some highly selected IO patients without concurring acquired risk factors. This NGS-based "second level" genetic test may represent a useful tool for molecular diagnosis of HH in patients in whom HH phenotype remains unexplained after the search of common HFE mutations.

Genomic analyses identify molecular subtypes of pancreatic cancer

Integrated genomic analysis of 456 pancreatic ductal adenocarcinomas identified 32 recurrently mutated genes that aggregate into 10 pathways: KRAS, TGF-β, WNT, NOTCH, ROBO/SLIT signalling, G1/S transition, SWI-SNF, chromatin modification, DNA repair and RNA processing. Expression analysis defined 4 subtypes: (1) squamous; (2) pancreatic progenitor; (3) immunogenic; and (4) aberrantly differentiated endocrine exocrine (ADEX) that correlate with histopathological characteristics. Squamous tumours are enriched for TP53 and KDM6A mutations, upregulation of the TP63∆N transcriptional network, hypermethylation of pancreatic endodermal cell-fate determining genes and have a poor prognosis. Pancreatic progenitor tumours preferentially express genes involved in early pancreatic development (FOXA2/3, PDX1 and MNX1). ADEX tumours displayed upregulation of genes that regulate networks involved in KRAS activation, exocrine (NR5A2 and RBPJL), and endocrine differentiation (NEUROD1 and NKX2-2). Immunogenic tumours contained upregulated immune networks including pathways involved in acquired immune suppression. These data infer differences in the molecular evolution of pancreatic cancer subtypes and identify opportunities for therapeutic development.

Pancreatic Neuroendocrine Neoplasms: Clinical Value of Diffusion-Weighted Imaging

BACKGROUND/AIMS

Diffusion-weighted imaging (DWI) can depict random motions of water molecules in biological tissues during magnetic resonance (MR) examinations. Few papers have tested its application to pancreatic neuroendocrine neoplasms (PanNENs). The aim of this paper is to assess the clinical value of DWI regarding the identification and characterization of PanNENs and diagnosis of liver metastases.

METHODS

Preoperative MR examinations of 30 PanNEN patients were retrospectively reviewed; 30 patients with pathologically proven pancreatic ductal adenocarcinoma (PDAC) were included to compare the imaging features. Qualitative and quantitative MR features were compared between histotypes. A blinded-reader comparison of diagnostic confidence for PanNENs and liver metastases was conducted on randomized image sets. All results were compared with pathological data.

RESULTS

PanNEN conspicuity was higher on DW images compared to conventional MR sequences. DWI had higher detection rates for PanNENs than had conventional sequences (93.3 vs. 71.1%). Sharp margins and absence of main pancreatic duct/common bile duct dilation and chronic pancreatitis were more common among PanNENs as compared to PDACs. Arterial iso- or hyperenhancement and portal hyperenhancement were more frequent within PanNENs as compared to PDACs. No differences between histotypes were found for quantitative features. Arterial-phase images had the highest interobserver agreement for the diagnosis of PanNEN (Cohen's κ = 0.667). DWI provided the highest detection rate for liver metastases as well as excellent interobserver agreement for the diagnosis of liver metastases (κ = 0.932), with good accuracy (AUC = 0.879-0.869).

CONCLUSION

DWI has clinical value regarding the identification of PanNENs and the diagnosis of liver metastases, while conventional MR sequences are fundamental for their characterization.

Prognostic impact and implications of extracapsular lymph node involvement in colorectal cancer: a systematic review with meta-analysis

BACKGROUND

The extranodal extension (ENE) of nodal metastasis (i.e. the extension of tumor cells through the nodal capsule into the perinodal adipose tissue) has recently emerged as an important prognostic factor in different types of malignancies. However, the tumor-node-metastasis (TNM) staging system for colorectal cancer does not consider it as a prognostic parameter. Therefore, we conducted a systematic review and meta-analysis to determine the prognostic role of ENE in patients with lymph node-positive colorectal cancer.

MATERIALS AND METHODS

Two independent authors searched PubMed and SCOPUS until 7 January 2015 without language restrictions. Prospective studies reporting data on prognostic parameters in subjects with colorectal cancer, comparing participants with the presence of ENE (ENE+) versus only intranodal extension (ENE-) were eligible. Data were summarized using risk ratios (RRs) for the number of deaths/recurrences and hazard ratios (HRs) together with 95% confidence intervals (CIs) for time-dependent risk related to ENE+, adjusted for potential confounders.

RESULTS

Thirteen studies including 1336 patients were identified with a median follow-up of 4.7 years. ENE was associated with a higher T stage and tumor grading. In addition, ENE was associated with a significantly increased risk of all-cause mortality (RR = 1.75; 95% CI 1.42-2.16, P < 0.0001, I(2) = 60%; HR = 1.69, 95% CI 1.32-2.17, P < 0.0001, I(2) = 46%) and of recurrence of disease (RR = 2.07, 95% CI 1.65-2.61, P < 0.0001, I(2) = 47%; HR = 2.31, 95% CI 1.54-3.44, P < 0.0001, I(2) = 48%).

CONCLUSIONS

Based of these results, in colorectal cancer, ENE should be considered from the gross sampling to the pathology report, as well as in future oncologic staging systems.

Prognostic implications of extranodal extension in node-positive squamous cell carcinoma of the vulva: A systematic review and meta-analysis

Squamous cell carcinoma (SCC) of the vulva is the fourth most common gynecological cancer, usually staged with the TNM or FIGO systems. Since 2009, FIGO staging has taken the extranodal extension (ENE) of lymph node metastases into account. ENE is defined as the spread of a lymph node metastasis into surrounding soft tissue. Although the TNM and FIGO systems acknowledge the importance of ENE in SCC, no comprehensive studies have analyzed the prognostic impact of this parameter. We therefore queried the PubMed and SCOPUS databases from their inception up until 04/01/2015, adopting no language restrictions: all prospective studies reporting on prognostic parameters in patients with vulvar SCC, and comparing participants with and without ENE were eligible for our analysis. Data were summarized using risk ratios (RR) for the number of deaths/recurrences and hazard ratios (HR) for the time-dependent risk related to ENE positivity, adjusting for potential confounders. Among 859 hits, 13 studies were found eligible and were included in our meta-analysis. Compared with ENE-negative (ENE-) cases, the ENE-positive (ENE+) patients had significantly higher rates of all-cause mortality (6 studies: RR = 3.18; 95%CI: 2.02-5.00, p < 0.0001, I(2) = 56%), cancer-specific mortality (3 studies: RR = 2.03; 95%CI: 1.12-3.69, p = 0.02, I(2) = 80%), and recurrence (4 studies: RR = 2.69, 95%CI: 1.61-3.76, p < 0.0001, I(2) = 57%). Using HRs after adjusting for potential confounders, ENE + carried a significantly higher risk of all-cause mortality (6 studies: HR = 3.08, 95%CI: 1.73-5.48, p < 0.0001, I(2) = 66%), and recurrence (5 studies: HR = 3.93, 95%CI: 2.33-6.62, p < 0.0001, I(2) = 28%). Our meta-analysis clarifies the prognostic significance of ENE in vulvar SCC, also pointing to its implications for gross sampling, histology and oncological staging.

Liver resection for hepatocellular carcinoma in patients with metabolic syndrome: A multicenter matched analysis with HCV-related HCC

BACKGROUND & AIMS

The incidence of metabolic syndrome-related hepatocellular carcinoma (MS-HCC) is increasing worldwide. High resection risks are anticipated because of underlying steatohepatitis, but long-term results are unknown. To clarify the outcomes following liver resection in patients with MS-HCC and to compare the outcomes of MS-HCC to HCV-related HCC (HCV-HCC).

METHODS

All the consecutive patients undergoing liver resection for HCC in six high-volume HPB units between 2000 and 2012 were retrospectively considered. The patients with MS-HCC were identified and matched one-to-one with HCV-HCC patients without metabolic syndrome. Matching was based on age, cirrhosis, Child-Pugh class, portal hypertension, HCC number and diameter and liver resection extension.

RESULTS

Among 1563 patients undergoing liver resection for HCC in the study period, 96 (6.1%) had MS-HCC. They were matched with 96 HCV-HCC patients. All patients were Child-Pugh class A, 22.9% had cirrhosis. Forty-one patients per group (42.7%) required major hepatectomy. The MS-HCC group had a higher prevalence of steatohepatitis (25.0% vs. 9.4%, p=0.004). Operative mortality was 2.1% (1 MS-HCC, 3 HCV-HCC, p=0.621). Morbidity and liver failure rates were similar between the two groups. In the multivariate analysis, cirrhosis, major hepatectomy, and MELD >8, but not steatohepatitis, impacted severe morbidity and liver failure rates. The MS-HCC group had better 5-year overall survival (65.6% vs. 61.4%, p=0.031) and recurrence-free survival (37.0% vs. 27.5%, p=0.077). Independent negative prognostic factors were HCV-HCC, multiple HCC, microvascular invasion, and satellite nodules.

CONCLUSIONS

Liver resection is safe for MS-HCC, as for HCV-HCC. Cirrhosis, but not steatohepatitis, affects short-term outcomes. MS-HCC is associated with excellent long-term outcomes, better than HCV-HCC.

Reappraisal of Nodal Staging and Study of Lymph Node Station Involvement in Pancreaticoduodenectomy with the Standard International Study Group of Pancreatic Surgery Definition of Lymphadenectomy for Cancer

BACKGROUND

The prognostic role of lymph node (LN) dissection in pancreatic head ductal adenocarcinoma is still unclear. This study reappraised the value of the number of positive LNs and LN ratio in patients undergoing pancreaticoduodenectomy with standard lymphadenectomy according to the recent International Study Group of Pancreatic Surgery definition. In addition, the impact of nodal metastases stratified by LN stations was investigated.

STUDY DESIGN

After reviewing retrospectively clinical and pathologic data of 758 pancreaticoduodenectomies for pancreatic head ductal adenocarcinoma performed from 2002 through 2011, we extracted patients in whom the LN stations included in the International Study Group of Pancreatic Surgery definition had been sampled. Survival analysis was performed using univariate and multivariate models.

RESULTS

The study population consisted of 255 patients. Mean number of harvested LNs was 30.8. Factors with a significant prognostic impact on multivariate analysis were tumor grade, adjuvant therapy, number of positive LNs, LN metastases along station 14a-b (proximal superior mesenteric artery), and the number of metastatic LN stations. Patients with involvement of station 14a-b exhibited worse pathologic features, indicating more aggressive disease.

CONCLUSIONS

In patients receiving a uniform LN dissection, the number of positive LNs is superior to LN ratio for predicting survival. Lymph node metastases along the proximal superior mesenteric artery have a significant prognostic value, and an increasing number of metastatic stations are associated with a sharp decrease in survival. In future studies, clarification of the pattern of LN metastasis spread could offer valuable insight into the optimal treatment strategies, including selection of patients for neoadjuvant therapies.

High-throughput mutation profiling identifies novel molecular dysregulation in high-grade intraepithelial neoplasia and early gastric cancers

BACKGROUND

There is still no widely accepted molecular marker available to distinguish between gastric high-grade intraepithelial neoplasia (HG-IEN) and invasive early gastric cancer (EGC).

METHODS

HG-IEN and EGC lesions coexisting in the same patient were manually microdissected from a series of 15 gastrectomies for EGC; 40 ng DNA was used for multiplex PCR amplification using the Ion AmpliSeq Cancer Panel, which explores the mutational status of hotspot regions in 50 cancer-associated genes.

RESULTS

Of the 15 EGCs, 12 presented at least one somatic mutation among the 50 investigated genes, and 6 of these showed multiple driver gene somatic mutations. TP53 mutations were observed in 9 cases; APC mutations were identified in 3 cases; and ATM and STK11 were mutated in 2 cases. Seven HG-IEN lesions shared an identical mutational profile with the EGC from the same patient; 13 mutations observed in APC, ATM, FGFR3, PIK3CA, RB1, STK11, and TP53 genes were shared by both HG-IEN and ECG lesions. CDKN2A, IDH2, MET, and RET mutations were observed only in EGC. TP53 deregulation was further investigated in an independent series of 75 biopsies corresponding to all the phenotypic lesions occurring in the EGC carcinogenetic cascade. p53 nuclear immunoreaction progressively increased along with the dedifferentiation of the lesions (P < 0.001). Overall, 18 of 20 p53-positive lesions showed a TP53 mutated gene.

DISCUSSION

Our results support the molecular similarity between HG-IEN and EGC and suggest a relevant role for TP53 in the progression to the invasive phenotype and the use of immunohistochemistry as a surrogate to detect TP53 gene mutations.

Targeted next-generation sequencing of cancer genes dissects the molecular profiles of intraductal papillary neoplasms of the pancreas

Intraductal neoplasms are important precursors to invasive pancreatic cancer and provide an opportunity to detect and treat pancreatic neoplasia before an invasive carcinoma develops. The diagnostic evaluation of these lesions is challenging, as diagnostic imaging and cytological sampling do not provide accurate information on lesion classification, the grade of dysplasia or the presence of invasion. Moreover, the molecular driver gene mutations of these precursor lesions have yet to be fully characterized. Fifty-two intraductal papillary neoplasms, including 48 intraductal papillary mucinous neoplasms (IPMNs) and four intraductal tubulopapillary neoplasms (ITPNs), were subjected to the mutation assessment in 51 cancer-associated genes, using ion torrent semiconductor-based next-generation sequencing. P16 and Smad4 immunohistochemistry was performed on 34 IPMNs and 17 IPMN-associated carcinomas. At least one somatic mutation was observed in 46/48 (96%) IPMNs; 29 (60%) had multiple gene alterations. GNAS and/or KRAS mutations were found in 44/48 (92%) of IPMNs. GNAS was mutated in 38/48 (79%) IPMNs, KRAS in 24/48 (50%) and these mutations coexisted in 18/48 (37.5%) of IPMNs. RNF43 was the third most commonly mutated gene and was always associated with GNAS and/or KRAS mutations, as were virtually all the low-frequency mutations found in other genes. Mutations in TP53 and BRAF genes (10% and 6%) were only observed in high-grade IPMNs. P16 was lost in 7/34 IPMNs and 9/17 IPMN-associated carcinomas; Smad4 was lost in 1/34 IPMNs and 5/17 IPMN-associated carcinomas. In contrast to IPMNs, only one of four ITPNs had detectable driver gene (GNAS and NRAS) mutations. Deep sequencing DNA from seven cyst fluid aspirates identified 10 of the 13 mutations detected in their associated IPMN. Using next-generation sequencing to detect cyst fluid mutations has the potential to improve the diagnostic and prognostic stratification of pancreatic cystic neoplasms.

Application of international consensus diagnostic criteria to an Italian series of autoimmune pancreatitis

BACKGROUND

International consensus diagnostic criteria (ICDC) have been proposed to classify autoimmune pancreatitis (AIP) in type 1, type 2, or not otherwise specified.

OBJECTIVE

Aim was to apply the ICDC to an Italian series of patients to evaluate the incidence and clinical profiles among different subtypes of AIP.

METHODS

we re-evaluated and classified 92 patients diagnosed by Verona criteria, according to the ICDC.

RESULTS

Out of 92 patients, 59 (64%) were diagnosed as type 1, 17 (18%) as type 2, and 15 (16%) as not otherwise specified according to the ICDC. A significant difference between type 1 and type 2 were found for age (54.5 ± 14.5 vs. 34.4 ± 13.9 respectively; p < 0.0001), male sex (76 vs. 47%; p = 0.007), jaundice (66 vs. 18%; p = 0.002) and acute pancreatitis (9 vs. 47%; p < 0.0001), elevated serum IgG4 levels (85 vs. 7%; p < 0.0001), inflammatory bowel disease (8 vs. 82%; < 0.0001), and relapse of the disease (34 vs. 6%; p = 0.058). Imaging and response to steroids in the not-otherwise-specified group were similar to type 1 and 2.

CONCLUSIONS

Type 1 has a different clinical profile from type 2 autoimmune pancreatitis. The not-otherwise-specified group has peculiar clinical features which are shared both with type 1 or type 2 groups.

Pancreatic hepatoid carcinoma: a review of the literature

BACKGROUND

Hepatoid carcinomas (HCs) are extrahepatic neoplasms exhibiting features of hepatocellular tumors in terms of morphology and immunohistochemistry. They have been described in several organs, most notably in the stomach and ovary. They can present in pure forms or in association with other morphological aspects, such as endocrine tumors or ductal adenocarcinomas. The aim of this review is to describe aspects of hepatoid adenocarcinoma of the pancreas with regard to epidemiology, diagnosis, and treatment.

METHODS

The PubMed database was searched for publications addressing hepatoid adenocarcinoma of the pancreas. We have searched for articles including the following keywords: 'pancreatic hepatoid carcinoma', 'ectopic liver cancer' and 'rare pancreas neoplasm' published to date. As references, we used case reports and review articles.

RESULTS

Pancreatic forms of HCs are extremely uncommon: only 22 cases have been reported.

CONCLUSIONS

The possibility of an HC of the pancreas should be considered in the differential diagnosis of an uncommon pathological mass of the pancreas. Treatment seems to be related to the association with other neoplasms, tumor extension at the time of diagnosis and the possibility to perform a radical resection. The common embryologic origin of the pancreas and liver, together with peculiar environmental factors, may explain the development of pancreatic HCs.

Exome sequencing identifies frequent inactivating mutations in BAP1, ARID1A and PBRM1 in intrahepatic cholangiocarcinomas

Through exomic sequencing of 32 intrahepatic cholangiocarcinomas, we discovered frequent inactivating mutations in multiple chromatin-remodeling genes (including BAP1, ARID1A and PBRM1), and mutation in one of these genes occurred in almost half of the carcinomas sequenced. We also identified frequent mutations at previously reported hotspots in the IDH1 and IDH2 genes encoding metabolic enzymes in intrahepatic cholangiocarcinomas. In contrast, TP53 was the most frequently altered gene in a series of nine gallbladder carcinomas. These discoveries highlight the key role of dysregulated chromatin remodeling in intrahepatic cholangiocarcinomas.

A re-emerging marker for prognosis in hepatocellular carcinoma: the add-value of fishing c-myc gene for early relapse

Hepatocellular carcinoma is one leading cause of cancer-related death and surgical resection is still one of the major curative therapies. Recently, there has been a major effort to find mechanisms involved in carcinogenesis and early relapse. c-myc gene abnormality is found in hepatocarcinogenesis. Our aim was to analyze the role of c-myc as prognostic factor in terms of overall survival and disease-free survival and to investigate if c-myc may be an important target for therapy. We studied sixty-five hepatocellular carcinomas submitted to surgical resection with curative intent. Size, macro-microvascular invasion, necrosis, number of nodules, grading and serum alfa-fetoprotein level were registered for all cases. We evaluated the c-myc aberrations by using break-apart FISH probes. Probes specific for the centromeric part of chromosome 8 and for the locus specific c-myc gene (8q24) were used to assess disomy, gains of chromosomes (polysomy due to polyploidy) and amplification. c-myc gene amplification was scored as 8q24/CEP8 > 2. Statistical analysis for disease-free survival and overall survival were performed. At molecular level, c-myc was amplified in 19% of hepatocellular carcinoma, whereas showed gains in 55% and set wild in 26% of cases. The 1- and 3-year disease-free survival and overall survival for disomic, polysomic and amplified groups were significantly different (p=0.020 and p=.018 respectively). Multivariate analysis verified that the AFP and c-myc status (amplified vs. not amplified) were significant prognostic factors for overall patients survival. c-myc gene amplification is significantly correlated with disease-free survival and overall survival in patients with hepatocellular carcinoma after surgical resection and this model identifies patients with risk of early relapse (≤12 months). We suggest that c-myc assessment may be introduced in the clinical practice for improving prognostication (high and low risk of relapse) routinely and may have be proposed as biomarker of efficacy to anti-c-myc targeted drugs in clinical trials.

Non-hyperfunctioning neuroendocrine tumours of the pancreas: MR imaging appearance and correlation with their biological behaviour

OBJECTIVE

To describe MR imaging features of non-hyperfunctioning neuroendocrine pancreatic tumours by comparing them to histopathology and to determine the accuracy of MR imaging in predicting biological behaviour.

MATERIALS AND METHODS

After institutional review board approval, we retrospectively reviewed 45 patients with pathologically proven NF-NET of the pancreas and ≥1 preoperative MR/MRCP examinations. Of the NF-NETS, 29/45 (64.4 %) were G1 and 16/45 (35.5 %) were G2. Image analysis included the lesion maximum diameter, vascular encasement, extrapancreatic spread, signal intensity on T1- and T2-weighted, contrast enhancement features, and presence of metastases. Tumour vessel density was calculated on the histological specimen using a grid.

RESULTS

The median maximum diameter of NF-NETs was 20 mm (range 5-200 mm). Eighty per cent of the NF-NETs were hypointense on T1-weighted images, 82.2 % were hyperintense on T2-weighted images, and 75.6 % were hypervascular. Overall MRI accuracy showed a mean AUC of 0.86 compared to pathology. Lesions with a maximum diameter of 30 mm irregular margins, absence of a cleavage plane with the main pancreatic duct, vascular encasement, extrapancreatic spread and abdominal metastases were significantly associated with malignant NF-NETs. No correlation was found between the tumour vessel density and contrast-enhanced MR imaging pattern.

CONCLUSIONS

Hyperintensity on T2-weighted images and iso-/hypervascularity occurred in 27/45 (60.0 %) of NF-NETs. MRI identifies malignant NF-NETs with a sensitivity of 93.3 % and a specificity of 76.9 % (AUC = 0.85).

KEY POINTS

• Non-hyperfunctioning neuroendocrine pancreatic tumours (NF-NET) pose a difficult diagnostic challenge. • On T2-weighted MRI, 82.2 % of neuroendocrine tumours appeared hyperintense. • MR imaging showed 0.94 sensitivity and 0.77 specificity in predicting biological behaviour. • The hyper-/isointensity during dynamic MRI did not correlate with vessel density at pathology.

ProNGF\NGF imbalance triggers learning and memory deficits, neurodegeneration and spontaneous epileptic-like discharges in transgenic mice

ProNGF, the precursor of mature nerve growth factor (NGF), is the most abundant form of NGF in the brain. ProNGF and mature NGF differ significantly in their receptor interaction properties and in their bioactivity. ProNGF increases markedly in the cortex of Alzheimer's disease (AD) brains and proNGF\NGF imbalance has been postulated to play a role in neurodegeneration. However, a direct proof for a causal link between increased proNGF and AD neurodegeneration is lacking. In order to evaluate the consequences of increased levels of proNGF in the postnatal brain, transgenic mice expressing a furin cleavage-resistant form of proNGF, under the control of the neuron-specific mouse Thy1.2 promoter, were derived and characterized. Different transgenic lines displayed a phenotypic gradient of neurodegenerative severity features. We focused the analysis on the two lines TgproNGF#3 and TgproNGF#72, which shared learning and memory impairments in behavioral tests, cholinergic deficit and increased Aβ-peptide immunoreactivity. In addition, TgproNGF#3 mice developed Aβ oligomer immunoreactivity, as well as late diffuse astrocytosis. Both TgproNGF lines also display electrophysiological alterations related to spontaneous epileptic-like events. The results provide direct evidence that alterations in the proNGF/NGF balance in the adult brain can be an upstream driver of neurodegeneration, contributing to a circular loop linking alterations of proNGF/NGF equilibrium to excitatory/inhibitory synaptic imbalance and amyloid precursor protein (APP) dysmetabolism.

Poorly differentiated resectable pancreatic cancer: is upfront resection worthwhile?

BACKGROUND

Poorly differentiated, resectable pancreatic ductal adenocarcinoma is associated with early recurrence and may benefit from neoadjuvant treatment. The aim of this study was to evaluate clinicopathologic characteristics and survival of patients with resectable pancreatic ductal adenocarcinoma according to histologic grading.

METHODS

A total of 502 patients who underwent resection for pancreatic ductal adenocarcinoma between 1990 and 2008 were analyzed via the use of different histologic grading.

RESULTS

Well-differentiated (G1), moderately differentiated (G2), and poorly differentiated (G3) pancreatic ductal adenocarcinomas were found in 23 (4.5%), 310 (62%), and 169 (33.5%) patients. Adjuvant therapy, N status, grading, and R status were independent predictors of disease-specific survival for the entire cohort, with 1- and 5-year disease-specific survival rates of 81% and 21%, respectively. Only the presence of symptoms was a significant clinical predictor of G3 status (P = .035). G3 neoplasms were characterized by a greater rate of lymph node metastases, microvascular/perineural invasion, and R2 resections. Median disease-specific survival was 77, 26, and 20 months for G1, G2, and G3 neoplasms (P < .0001). Median disease-free survival was 63, 14, and 9 months for G1, G2, and G3 pancreatic ductal adenocarcinoma (P < .0001). Adjuvant therapy improved disease-specific survival in G2 (P < .04) and G3 (P < .0001) pancreatic ductal adenocarcinoma, with a greater survival benefit for G3 neoplasms (hazard ratio: 1.334 vs 2.116).

CONCLUSION

G3 pancreatic ductal adenocarcinoma is associated with a lesser rate of disease-free survival after resection and with the presence of other poor prognostic factors. The benefit of adjuvant therapy is greater in G3 than in G1 and G2 neoplasms. On the basis of these findings, patients with resectable G3 PDAC can be considered as possible targets for neoadjuvant treatment.