CD200 expression is a feature of solid pseudopapillary neoplasms of the pancreas

CD200 has been recently indicated as a robust marker of well-differentiated neuroendocrine neoplasms. Here, we evaluate its role in differential diagnosis of solid pancreatic neoplasms. We immunostained for CD200 22 solid pseudopapillary neoplasms (SPNs), 8 acinar carcinomas (ACs), 2 pancreatoblastomas (PBs), 138 neuroendocrine tumors (PanNETs), and 48 ductal adenocarcinomas. All SPNs showed strong cytoplasmic and membranous staining for CD200, while only one case of AC had focal positivity. The two PBs showed focal CD200 positivity, mainly located in squamoid nests. The vast majority of PanNETs (96%) showed strong cytoplasmic and membranous staining for CD200, whereas all PDACs were negative. As both PanNETs and SPNs express CD200, it has no role in the differential diagnosis between these two entities.

CT Texture Analysis of Ductal Adenocarcinoma Downstaged After Chemotherapy

BACKGROUND/AIM

Re-staging of ductal adenocarcinoma using computed tomography (CT) scan can be problematic so new imaging techniques and evaluation parameters are required. The aim of the study was to evaluate the added value of CT texture analysis in estimation of tissue changes in ductal adenocarcinoma downsized and resected after chemotherapy.

MATERIALS AND METHODS

Patients with ductal adenocarcinoma downstaged after neoadjuvant treatment, and resected, were included. A pre- and post-treatment CT was obtained. In comparison, patients with disease progression were included for texture analysis evaluation at CT pre- and post-treatment. CT texture analysis results were compared.

RESULTS

A total of 17 patients affected by un-resectable or borderline ductal adenocarcinoma reached the resectable stage after treatment. The comparison between Kurtosis pre- and Kurtosis post-treatment showed a statistically significant difference. On the contrary, in the comparison group composed of 14 patients with disease progression there was no statistical difference regarding this parameter.

CONCLUSION

This evaluation may represent an added value in tumor tissue changes judgment and can be extremely useful to diagnose downstaging in those cases with no evident downsizing after chemotherapy.

PD-1, PD-L1, and CD163 in pancreatic undifferentiated carcinoma with osteoclast-like giant cells: expression patterns and clinical implications

Undifferentiated carcinoma with osteoclast-like giant cells (UCOGC), a variant of pancreatic ductal adenocarcinoma (PDAC), has a striking genetic similarity to PDAC but a significantly improved overall survival. We hypothesize that this difference could be due to the immune response to the tumor, and as such, we investigated the expression of PD-1, PD-L1, and CD163 in a series of UCOGC. To this aim, 27 pancreatic UCOGCs (11 pure and 16 PDAC-associated), 5 extrapancreatic tumors with osteoclast-like giant cells and 10 pancreatic anaplastic carcinomas were immunostained using antibodies against PD-1, PD-L1, and CD163. In pancreatic UCOGCs, PD-L1 was expressed in neoplastic cells of 17 (63%) of 27 cases, more often in cases with an associated PDAC (P = .04). Expression of PD-L1 was associated with poor prognosis, confirmed by multivariate analysis: patients with PD-L1-positive UCOGCs had a risk of all-cause mortality that was 3 times higher than did patients with PD-L1-negative UCOGCs (hazard ratio, 3.397; 95% confidence interval, 1.023-18.375; P = .034). PD-L1 expression on tumor cells was also associated with aberrant P53 expression (P = .035). PD-1 was expressed on rare lymphocytes in 12 UCOGCs (44.4%), mainly located at the tumor periphery. CD163 was expressed on histiocytes, with a diffuse and strong staining pattern in all UCOGCs. Extrapancreatic tumors with osteoclast-like giant cells showed very similar staining patterns for the same proteins. Anaplastic carcinomas have some similarities to UCOGCs, but PD-L1 has no prognostic roles. Our results may have important implications for immunotherapeutic strategies in UCOGCs; these tumors may also represent a model for future therapeutic approaches against PDAC.

Can histogram analysis of MR images predict aggressiveness in pancreatic neuroendocrine tumors?

OBJECTIVES

To evaluate MRI derived whole-tumour histogram analysis parameters in predicting pancreatic neuroendocrine neoplasm (panNEN) grade and aggressiveness.

METHODS

Pre-operative MR of 42 consecutive patients with panNEN >1 cm were retrospectively analysed. T1-/T2-weighted images and ADC maps were analysed. Histogram-derived parameters were compared to histopathological features using the Mann-Whitney U test. Diagnostic accuracy was assessed by ROC-AUC analysis; sensitivity and specificity were assessed for each histogram parameter.

RESULTS

ADC_entropy was significantly higher in G2-3 tumours with ROC-AUC 0.757; sensitivity and specificity were 83.3 % (95 % CI: 61.2-94.5) and 61.1 % (95 % CI: 36.1-81.7). ADC_kurtosis was higher in panNENs with vascular involvement, nodal and hepatic metastases (p= .008, .021 and .008; ROC-AUC= 0.820, 0.709 and 0.820); sensitivity and specificity were: 85.7/74.3 % (95 % CI: 42-99.2 /56.4-86.9), 36.8/96.5 % (95 % CI: 17.2-61.4 /76-99.8) and 100/62.8 % (95 % CI: 56.1-100/44.9-78.1). No significant differences between groups were found for other histogram-derived parameters (p >.05).

CONCLUSIONS

Whole-tumour histogram analysis of ADC maps may be helpful in predicting tumour grade, vascular involvement, nodal and liver metastases in panNENs. ADC_entropy and ADC_kurtosis are the most accurate parameters for identification of panNENs with malignant behaviour.

KEY POINTS

• Whole-tumour ADC histogram analysis can predict aggressiveness in pancreatic neuroendocrine neoplasms. • ADC entropy and kurtosis are higher in aggressive tumours. • ADC histogram analysis can quantify tumour diffusion heterogeneity. • Non-invasive quantification of tumour heterogeneity can provide adjunctive information for prognostication.

Are Cystic Pancreatic Neuroendocrine Tumors an Indolent Entity Results from a Single-Center Surgical Series

INTRODUCTION

Cystic pancreatic neuroendocrine tumors (CPanNETs) represent an uncommon variant of pancreatic neuroendocrine tumors (PanNETs). Due to their rarity, there is a lack of knowledge with regard to clinical features and postoperative outcome.

METHODS

The prospectively maintained surgical database of a high-volume institution was queried, and 46 resected CPanNETs were detected from 1988 to 2015. Clinical, demographic, and pathological features and survival outcomes of CPanNETs were described and matched with a population of 92 solid PanNETs (SPanNETs) for comparison.

RESULTS

CPanNETs accounted for 7.8% of the overall number of resected PanNETs (46/587). CPanNETs were mostly sporadic (n = 42, 91%) and nonfunctioning (39%). Two functioning CPanNETs were detected (4.3%), and they were 2 gastrinomas. The median tumor diameter was 30 mm (range 10-120). All tumors were well differentiated, with 38 (82.6%) G1 and 8 (17.4%) G2 tumors. Overall, no CPanNET showed a Ki-67 >5%. A correct preoperative diagnosis of a CPanNET was made in half of the cases. After a median follow-up of >70 months, the 5- and 10-year overall survival of resected CPanNETs was 93.8 and 62.5%, respectively, compared to 92.7 and 84.6% for SPanNETs (p > 0.05). The 5- and 10-year disease-free survival rates were 94.5 and 88.2% for CPanNETs and 81.8 and 78.9% for SPanNETs, respectively (p > 0.05).

CONCLUSION

In the setting of a surgical cohort, CPanNETs are rare, nonfunctional, and well-differentiated neoplasms. After surgical resection, they share the excellent outcome of their well-differentiated solid counterparts for both survival and recurrence.

Fast Chromotrope Aniline Blue Special Stain Is a Useful Tool to Assess Fibrosis on Liver Biopsy During Transplantation

BACKGROUND

Assessment of potential liver allograft donors with frozen sections has clinical relevant consequences for the transplant recipient. Several clinical risk factors have been identified that increase the risk of transplantation failure and it is critical for the pathologist to become familiar with the histologic criteria for donor liver suitability. In this setting an accurate and reliable assessment of fibrosis is crucial. We sought to report the value of the rapid chromotrope aniline blue stain (CAB) in a transplantation clinical work-flow for scoring liver fibrosis.

MATERIALS AND METHODS

Twenty consecutive intraoperative donor liver biopsy specimens were evaluated by a pathologist at the Transplant Pathology Board Room, AOUI Verona, during 24-hour on-call service. The stage of fibrosis was evaluated according to Ishak score ranging from 0 to 6 (absent to cirrhosis) using hematoxylin and eosin stain (H&E) plus rapid CAB special stain. After a 3-week washout period, only the slides stained with H&E were re-assessed for fibrosis stage by the same pathologist blinded to donor patient data.

RESULTS

Combination H&E-CAB staging fibrosis score was higher in 20%, lower in 10%, and the same in 70% of biopsy specimens as determined using only H&E stain alone. Rapid CAB stain takes 20 minutes longer than H&E stain alone.

CONCLUSIONS

CAB staining may be performed on frozen tissue from liver biopsy during a transplantation process without a significant delay in diagnosis. Combination H&E-CAB staining improves sensibility of interpretation of fibrosis.

Bowel obstruction in obturator hernia: A challenging diagnosis

•

Obturator hernia is a rare entity; delayed diagnosis and treatment are associated with high rate of morbidity.

•

It usually occurs in female and presents with bowel obstruction symptoms such as nausea, vomit and hydroelectrolyte imbalance.

•

Surgery is the unique treatment: both laparoscopic transabdominal or laparotomic approaches are proposed.

Introduction

The obturator hernia is a rare pelvic hernia that often comes in the shape of bowel obstruction caused by the presence of an intestinal segment, more often ileum, passing trough the obturator foramen of the pelvic wall (Fig. 1). This type of hernia accounts for 0.5-1.4% of all hernias.

Case presentation

We report the clinical case of a 84-year-old woman with no previous surgical interventions, who went to the emergency room complaining of vomit and nausea, bowels closed to gas and stool, which she had experienced for three previous days. Routine blood test showed impaired renal function and hydrohelectrolyte imbalance. A CT scan revealed a right ileal, strangulated obturator hernia. The patient underwent an emergency surgical intervention with laparoscopic trans-abdominal peritoneal approach (TAP): after the reduction of the herniated segment, a primary suturing of the parietal defect was performed without ileal resection.

Discussion

Because of the non-specific symptoms the diagnosis of this kind of hernia is often unclear; female are 6–9 times more likely than men to be subject to the aforementioned pathology, mostly occurring in multiparous, emaciated, elderly woman so it is also called “the little old lady’s hernia”. Risk factors are loss of weight, chronic pulmonary disease and ascites which increase the abdominal pressure. An unfrequent presenting sign is a palpable mass, or the Howship-Romberg sign- a pain radiating from the inner tigh and knee − but it could be misleading when confused with symptoms of gonarthrosis or lumbar vertebral disc pathology. CT scan has superior sensitivity and accuracy with respect to other radiological exams to assess the presence of an obturator hernia.

Conclusion

Obturator hernia is a rare type of hernia due to his diagnosis, which is often unclear; a prompt suspect based for the non-specific symptoms is crucial for the diagnosis. Surgical management depends on early diagnosis and it is the only possible treatment for this pathology.

Solid non-functioning endocrine tumors of the pancreas: correlating computed tomography and pathology

BACKGROUND

Since prognosis and treatment of pancreatic endocrine tumors (pNET) are based on tumor grade, contrast-enhanced multidetector computed tomography (MDCT) features of solid non-functioning pNETs were studied and correlated with pathology tumor grading.

METHODS

MDCTs of diagnosed pNETs were reviewed retrospectively. Each tumor was analyzed for location, size, homogeneity, margins, arterial and venous phase enhancement, main pancreatic duct diameter, calcifications, vascular invasion, lymph-nodes enlargement, and liver metastases.

RESULTS

Of 154 pNETs presenting between January 2000 and May 2016 with available histology from resected specimen or biopsy, there were 65 G1, 72 G2 and 17 G3 pNETs. Tumor diameter varied significantly between the three groups. Tumors >20 mm were more frequently malignant and non-homogeneous than smaller tumors. G1 tumors were more commonly hypervascular and G3 tumors more often non-hypervascular in the arterial phase. Arterial phase non-hyperdensity and tumor non-homogeneity had a higher rate of metastatic lesions. Vascular invasion correlated with presence of metastases and histological grade. G3 tumors were all >20 mm (p = 0.007), more often non-hypervascular in the arterial phase (p = 0.0025), and non-hyperdense in the venous phase (p = 0.009), and showed more often vascular invasion (p = 0.0198).

CONCLUSION

CT correlated with tumor grade; differentiating low-grade and high-grade pNETs through routine CT imaging might improve patient management.

Corrigendum: Whole-genome landscape of pancreatic neuroendocrine tumours

This corrects the article DOI: 10.1038/nature21063.

Pancreatic undifferentiated carcinoma with osteoclast-like giant cells is genetically similar to, but clinically distinct from, conventional ductal adenocarcinoma

Undifferentiated carcinoma of the pancreas with osteoclast-like giant cells (UCOGC) is currently considered a morphologically and clinically distinct variant of pancreatic ductal adenocarcinoma (PDAC). In this study, we report clinical and pathological features of a series of 22 UCOGCs, including the whole exome sequencing of eight UCOGCs. We observed that 60% of the UCOGCs contained a well-defined epithelial component and that patients with pure UCOGC had a significantly better prognosis than did those with an UCOGC with an associated epithelial neoplasm. The genetic alterations in UCOGC are strikingly similar to those known to drive conventional PDAC, including activating mutations in the oncogene KRAS and inactivating mutations in the tumor suppressor genes CDKN2A, TP53, and SMAD4. These results further support the classification of UCOGC as a PDAC variant and suggest that somatic mutations are not the determinants of the unique phenotype of UCOGC. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Pancreatectomy with venous resection for pT3 head adenocarcinoma: Perioperative outcomes, recurrence pattern and prognostic implications of histologically confirmed vascular infiltration

BACKGROUND

The outcomes of pancreatectomy with superior mesenteric vein (SMV) or portal vein (PV) resection have been mixed. This study investigated the morbidity and mortality profile after SMV-PV resection in comparison with standard pancreatectomy. Furthermore, we assessed whether tumors with histologically proven SMV-PV infiltration differ from other pT3 neoplasms in terms of recurrence pattern and survival.

METHODS

All patients with a pT3 head adenocarcinoma resected from 2000 to 2013 were analyzed retrospectively. In the SMV-PV resection group, information on venous wall status was obtained through pathologic reports. Standard statistical methods were used for data analysis.

RESULTS

The study population consisted of 651 patients, of whom 81 (12.4%) underwent synchronous SMV-PV resection. Venous resection was not associated with a higher rate of postoperative complications (60.5% versus 50.2%) and mortality (1.2% versus 1.1%) in comparison with standard pancreatectomy. Vascular infiltration was confirmed pathologically in 56/81 patients (69.1%). The median disease-specific survival of the entire population was 27 months (95% CI 24.6-29.3), with a 5-year survival rate of 20.5%. The median recurrence-free survival was 18 months (95% CI 15.0-20.9). On multivariate analysis, ASA score, preoperative pain, Ca 19-9 levels, tumor grade, R-status, lymph-vascular invasion, N-status, and adjuvant therapy resulted to be survival predictors. Similarly, Ca 19.9 levels, R-status, and N-status were predictors of recurrence. SMV-PV infiltration was not a significant prognostic factor.

CONCLUSION

Morbidity and mortality rates of pancreatectomy with SMV-PV resection are comparable with standard pancreatectomy. Pancreatic head adenocarcinoma with histologically confirmed SMV-PV infiltration does not segregate prognostically from other pT3 tumors.

Serous pancreatic neoplasia, data and review

AIM

To describe the imaging features of serous neoplasms of the pancreas using ultrasound, endoscopic ultrasound, computed tomography and magnetic resonance imaging.

METHODS

This multicenter international collaboration enhances a literature review to date, reporting features of 287 histologically confirmed cases of serous pancreatic cystic neoplasms (SPNs).

RESULTS

Female predominance is seen with most SPNs presenting asymptomatically in the 5^th through 7^th decade. Mean lesion size was 38.7 mm, 98% were single, 44.2% cystic, 46% mixed cystic and solid, and 94% hypoechoic on B-mode ultrasound. Vascular patterns and contrast-enhancement profiles are described as hypervascular and hyperenhancing.

CONCLUSION

The described ultrasound features can aid differentiation of SPN from other neoplastic lesions under most circumstances.

PBRM1 loss is a late event during the development of cholangiocarcinoma

AIMS

Somatic mutations in genes encoding chromatin remodellers have been reported recently in several cancer types, including approximately half of cholangiocarcinomas. One of the most commonly mutated chromatin remodellers in cholangiocarcinoma is the Polybromo-1 (PBRM1) gene located on chromosome 3p21, which encodes a subunit of the SWI/SNF complex. The aim of this study was to determine the timing of PBRM1 mutations in biliary carcinogenesis.

METHODS AND RESULTS

In order to accomplish this goal, we used immunohistochemistry to assess PBRM1 protein expression in a series of precursor lesions and invasive biliary carcinomas. Previous studies have correlated loss of protein expression on immunohistochemistry with inactivating mutations in this tumour suppressor gene. We found that PBRM1 loss occurred in approximately 26% of invasive cancers, but PBRM1 expression was retained in all biliary intra-epithelial neoplasia (BilIN) specimens, including 25 intrahepatic BilINs and 19 gallbladder BilINs.

CONCLUSIONS

These findings indicate that PBRM1 mutation (and resultant loss of expression) is a late event during biliary carcinogenesis. In addition, we confirm a lack of prognostic significance of PBRM1 status in invasive intrahepatic cholangiocarcinoma. This study provides important insights into the basic mechanisms of chromatin remodelling genes in carcinogenesis.

Downstaging in Stage IV Pancreatic Cancer: A New Population Eligible for Surgery?

BACKGROUND

Recent papers consider surgery as an option for synchronous liver oligometastatic patients [metastatic pancreatic ductal adenocarcinoma (mPDAC)]. In this study, we present our series of resected mPDACs after neoadjuvant chemotherapy (nCT).

PATIENTS AND METHODS

All patients resected after downstaging of mPDAC were included in this study. Downstaging criteria were disappearance of liver metastasis and a decrease in cancer antigen (CA) 19-9. The type and duration of nCT, last nCT surgery interval, histology, morbidity, and mortality were recorded, and overall survival (OS) and disease-free survival (DFS) were analyzed.

RESULTS

Overall, 24 of 535 patients (4.5%) observed with mPDAC were included. These patients received gemcitabine alone (5/24), gemcitabine + nanoparticle albumin-bound (nab)-paclitaxel (3/24), and FOLFIRINOX (16/24). Primary tumor size decreased from 31 to 19 mm (p < 0.001), and serum CA19-9 decreased from 596 to 18 U/mL (p < 0.001). In 14/24 patients, the tumor was located in the head. Median interval nCT surgery was 2 months, there were no mortalities, and the postoperative course was uneventful in 34% of cases. Grade B/C pancreatic fistula, postoperative bleeding, and sepsis occurred in 17/4, 4, and 12% of cases, respectively, and reoperation rate was 4%. R0 resection was achieved in 88% of cases, with 17% complete pathological response. Positive nodes were found in 9/24 patients with a median node ratio of 0.37, and OS and DFS was 56 and 27 months, respectively.

CONCLUSIONS

Patients with mPDAC who were fully responsive to nCT may be cautiously considered for surgery, with potential benefit in survival compared with palliative chemotherapy alone. This is supported by results of our retrospective study, which is the largest ever reported.

Comparison of imaging-based and pathological dimensions in pancreatic neuroendocrine tumors

AIM

To establish the ability of magnetic resonance (MR) and computer tomography (CT) to predict pathologic dimensions of pancreatic neuroendocrine tumors (PanNET) in a caseload of a tertiary referral center.

METHODS

Patients submitted to surgery for PanNET at the Surgical Unit of the Pancreas Institute with at least 1 preoperative imaging examination (MR or CT scan) from January 2005 to December 2015 were included and data retrospectively collected. Exclusion criteria were: multifocal lesions, genetic syndromes, microadenomas or mixed tumors, metastatic disease and neoadjuvant therapy. Bland-Altman (BA) and Mountain-Plot (MP) statistics were used to compare size measured by each modality with the pathology size. Passing-Bablok (PB) regression analysis was used to check the agreement between MR and CT.

RESULTS

Our study population consisted of 292 patients. Seventy-nine (27.1%) were functioning PanNET. The mean biases were 0.17 ± 7.99 mm, 1 ± 8.51 mm and 0.23 ± 9 mm, 1.2 ± 9.8 mm for MR and CT, considering the overall population and the subgroup of non-functioning- PanNET, respectively. Limits of agreement (LOA) included the vast majority of observations, indicating a good agreement between imaging and pathology. The MP further confirmed this finding and showed that the two methods are unbiased with respect to each other. Considering ≤ 2 cm non-functioning-PanNET, no statistical significance was found in the size estimation rate of MR and CT (P = 0.433). PBR analysis did not reveal significant differences between MR, CT and pathology.

CONCLUSION

MR and CT scan are accurate and interchangeable imaging techniques in predicting pathologic dimensions of PanNET.

Whole-genome landscape of pancreatic neuroendocrine tumours

The diagnosis of pancreatic neuroendocrine tumours (PanNETs) is increasing owing to more sensitive detection methods, and this increase is creating challenges for clinical management. We performed whole-genome sequencing of 102 primary PanNETs and defined the genomic events that characterize their pathogenesis. Here we describe the mutational signatures they harbour, including a deficiency in G:C > T:A base excision repair due to inactivation of MUTYH, which encodes a DNA glycosylase. Clinically sporadic PanNETs contain a larger-than-expected proportion of germline mutations, including previously unreported mutations in the DNA repair genes MUTYH, CHEK2 and BRCA2. Together with mutations in MEN1 and VHL, these mutations occur in 17% of patients. Somatic mutations, including point mutations and gene fusions, were commonly found in genes involved in four main pathways: chromatin remodelling, DNA damage repair, activation of mTOR signalling (including previously undescribed EWSR1 gene fusions), and telomere maintenance. In addition, our gene expression analyses identified a subgroup of tumours associated with hypoxia and HIF signalling.

Pancreatic neuroendocrine neoplasms: Magnetic resonance imaging features according to grade and stage

AIM

To describe magnetic resonance (MR) imaging features of pancreatic neuroendocrine neoplasms (PanNENs) according to their grade and tumor-nodes-metastases stage by comparing them to histopathology and to determine the accuracy of MR imaging features in predicting their biological behavior.

METHODS

This study was approved by our institutional review board; requirement for informed patient consent was waived due to the retrospective nature of the study. Preoperative MR examinations of 55 PanNEN patients (29 men, 26 women; mean age of 57.6 years, range 21-83 years) performed between June 2013 and December 2015 were reviewed. Qualitative and quantitative features were compared between tumor grades and stages determined by histopathological analysis.

RESULTS

Ill defined margins were more common in G2-3 and stage III-IV PanNENs than in G1 and low-stage tumors (P < 0.001); this feature had high specificity in the identification of G2-3 and stage III-IV tumors (90.3% and 96%, 95%CI: 73.1-97.5 and 77.7-99.8). The mean apparent diffusion coefficient value was significantly lower in G2-3 and stage III-IV lesions compared to well differentiated and low-stage tumors (1.09 × 10^-3 mm²/s vs 1.45 × 10^-3 mm²/s and 1.10 × 10^-3 mm²/s vs 1.53 × 10^-3 mm²/s, P = 0.003 and 0.001). Receiving operator characteristic analysis determined optimal cut-offs of 1.21 and 1.28 × 10^-3 mm²/s for the identification of G2-3 and stage III-IV tumors, with sensitivity and specificity values of 70.8/80.7% and 64.5/64% (95%CI: 48.7-86.6/60-92.7 and 45.4-80.2/42.6-81.3).

CONCLUSION

MR features of PanNENs vary according to their grade of differentiation and their stage at diagnosis and could predict the biological behavior of these tumors.

What is the most accurate lymph node staging method for perihilar cholangiocarcinoma? Comparison of UICC/AJCC pN stage, number of metastatic lymph nodes, lymph node ratio, and log odds of metastatic lymph nodes

BACKGROUND

We compared the prognostic performance of the International Union Against Cancer/American Joint Committee on Cancer (UICC/AJCC) 7th edition pN stage, number of metastatic LNs (MLNs), LN ratio (LNR), and log odds of MLNs (LODDS) in patients with perihilar cholangiocarcinoma (PCC) undergoing curative surgery in order to identify the best LN staging method.

METHODS

Ninety-nine patients who underwent surgery with curative intent for PCC in a single tertiary hepatobiliary referral center were included in the study. Two approaches were used to evaluate and compare the predictive power of the different LN staging methods: one based on the estimation of variable importance with prediction error rate and the other based on the calculation of the receiver operating characteristic (ROC) curve.

RESULTS

LN dissection was performed in 92 (92.9%) patients; 49 were UICC/AJCC pN0 (49.5%), 33 pN1 (33.3%), and 10 pN2 (10.1%). The median number of LNs retrieved was 8. The prediction error rate ranged from 42.7% for LODDS to 47.1% for UICC/AJCC pN stage. Moreover, LODDS was the variable with the highest area under the ROC curve (AUC) for prediction of 3-year survival (AUC = 0.71), followed by LNR (AUC = 0.60), number of MLNs (AUC = 0.59), and UICC/AJCC pN stage (AUC = 0.54).

CONCLUSIONS

The number of MLNs, LNR, and LODDS appear to better predict survival than the UICC/AJCC pN stage in patients undergoing curative surgery for PCC. Moreover, LODDS seems to be the most accurate and predictive LN staging method.

Role of Combined 68Ga-DOTATOC and 18F-FDG Positron Emission Tomography/Computed Tomography in the Diagnostic Workup of Pancreas Neuroendocrine Tumors: Implications for Managing Surgical Decisions

OBJECTIVES

Ga-DOTATOC (Ga) positron emission tomography (PET)/computed tomography (CT) is recommended in the workup of pancreas neuroendocrine tumors (PanNETs); evidence suggests that F-FDG (F) PET/CT can also provide prognostic information. Aims of this study were to assess the role of combined Ga- and F-PET/CT in the evaluation of grade (G) 1-2 PanNETs and to test the correlation between F-PET/CT positivity and tumor grade.

METHODS

Preoperative Ga- and F-PET/CT of 35 patients with surgically resected G1-2 PanNETs were evaluated. For grading, the 2010 World Health Organization Classification was used; an ancillary analysis with Ki67 cutoffs at 5% to 20% was conducted. Correlation between F-PET/CT positivity (SUVmax > 3.5) and grade was assessed.

RESULTS

Of 35 PanNETs, 28.6% and 71.4% were G1 and G2 as per World Health Organization. Ga-PET/CT showed high sensitivity (94.3%) in detecting G1-2 PanNETs. F-PET/CT was positive in 20% and 76% G1 and G2 tumors (P = 0.002). F-PET/CT identified G2 PanNETs with high positive predictive value (PPV, 90.5%). F-PET/CT correlated with tumor grade also in the ancillary analysis (P = 0.009).

CONCLUSIONS

The high sensitivity of Ga-PET/CT in NET detection is known. The high PPV of F-PET/CT in the identification of G2 forms suggests its potential role in PanNETs prognostication and risk stratification.

Prognostic role and implications of mutation status of tumor suppressor gene ARID1A in cancer: a systematic review and meta-analysis

Loss of the tumor suppressor gene AT-rich interactive domain-containing protein 1A (ARID1A) has been demonstrated in several cancers, but its prognostic role is unknown. We aimed to investigate the risk associated with loss of ARID1A (ARID1A−) for all-cause mortality, cancer-specific mortality and recurrence of disease in subjects with cancer. PubMed and SCOPUS search from database inception until 01/31/2015 without language restriction was conducted, contacting authors for unpublished data. Eligible were prospective studies reporting data on prognostic parameters in subjects with cancer, comparing participants with presence of ARID1A (ARID1A+) vs. ARID1A−, assessed either via immunohistochemistry (loss of expression) or with genetic testing (presence of mutation). Data were summarized using risk ratios (RR) for number of deaths/recurrences and hazard ratios (HR) for time-dependent risk related to ARID1A− adjusted for potential confounders. Of 136 hits, 25 studies with 5,651 participants (28 cohorts; ARID1A−: n = 1,701; ARID1A+: n = 3,950), with a mean follow-up period of 4.7 ± 1.8 years, were meta-analyzed. Compared to ARID1A+, ARID1A− significantly increased cancer-specific mortality (studies = 3; RR = 1.55, 95% confidence interval (CI) = 1.19–2.00, I² = 31%). Using HRs adjusted for potential confounders, ARID1A− was associated with a greater risk of cancer-specific mortality (studies = 2; HR = 2.55, 95%CI = 1.19–5.45, I² = 19%) and cancer recurrence (studies = 10; HR = 1.93, 95%CI = 1.22–3.05, I² = 76%). On the basis of these results, we have demonstrated that loss of ARID1A shortened time to cancer-specific mortality, and to recurrence of cancer when adjusting for potential confounders. For its role, this gene should be considered as an important potential target for personalized medicine in cancer treatment.

Pancreatic Ductal Adenocarcinoma and Its Variants

Pancreatic cancer represents the seventh leading cause of cancer death in the world, responsible for more than 300,000 deaths per year. The most common tumor type among pancreatic cancers is pancreatic ductal adenocarcinoma, an infiltrating neoplasm with glandular differentiation that is derived from pancreatic ductal tree. Here we present and discuss the most important macroscopic, microscopic, and immunohistochemical characteristics of this tumor, highlighting its key diagnostic features. Furthermore, we present the classic features of the most common variants of pancreatic ductal adenocarcinoma. Last, we summarize the prognostic landscape of this highly malignant tumor and its variants.

Extranodal Extension of Nodal Metastases Is a Poor Prognostic Indicator in Gastric Cancer: a Systematic Review and Meta-analysis

INTRODUCTION

The extranodal extension (ENE) of nodal metastases (the extension of neoplastic cells through the nodal capsule into the perinodal soft tissue) is a histological feature that has been considered a prognostic factor in several cancers, but the role in gastric cancer was not yet investigated. We aimed to investigate the prognostic role of ENE in patients affected by gastric cancer through a systematic review and meta-analysis.

MATERIAL AND METHODS

Two independent authors searched major databases until 09/30/2015 to identify studies providing data on gastric cancer patients' prognostic parameters and comparing patients with ENE (ENE+) vs intra-nodal extension (ENE-). The data were summarized using risk ratios (RRs) for the number of deaths/recurrences and hazard ratios (HRs) with 95 % confidence intervals (CI), adjusted for potential confounders.

RESULTS

Nine studies followed up 3250 patients with gastric cancer (1064 ENE+ and 2186 ENE-). ENE+ was associated with a significantly higher risk of all-cause mortality (RR = 1.70; 95 % CI: 1.43-2.03, I (2) = 66 %; HR = 2.14; 95 % CI: 1.66-2.75, I (2) = 0 %), cancer-specific mortality (RR = 1.59; 95 % CI: 1.42-1.79; HR = 1.52; 95 % CI: 1.19-1.96), and disease recurrence (RR = 3.43, 95 % CI: 1.80-6.54, I (2) = 0 %).

DISCUSSION

Judging from our results, ENE in gastric cancer patients should be considered for prognostic purposes from the gross sample to the pathology report.

Solid pseudopapillary tumors of the pancreas: Specific pathological features predict the likelihood of postoperative recurrence

BACKGROUND

Since their introduction in the WHO classification, the incidence of solid pseudopapillary tumors (SPTs) of the pancreas has progressively increased, mainly because of the widespread use of cross-sectional imaging. Few recent studies have analyzed the biological behavior of SPTs, but reliable data on long-term follow-up are needed.

METHODS

Retrospective analysis of two Institutions with high caseload, The Department of General Surgery-Pancreas Institute, University of Verona Hospital Trust and the Department of General Surgery, Massachusetts General Hospital, Harvard Medical School, was carried out. Data from 131 consecutive resections for SPT performed during the last three decades were collected and analyzed.

RESULTS

The majority of patients were female (86.3%) with a median age of 33 (7-68) years. The prevalent location was the pancreatic tail (33.5%). Applying the WHO criteria, 16 (12.2%) SPTs were considered malignant due to the presence of at least pancreatic parenchyma (9.9%), perineural (4.6%), and/or angiovascular invasion (2.3%). After a median of 62 months after surgery, only two patients had a recurrence (1.5%). Both of them fulfilled the WHO criteria for malignant SPT (vs. 10.7% of those who did not recur, P = 0.01), had an infiltrative growth pattern (vs. 10.8%, P = 0.01), pancreatic parenchyma invasion (vs. 9.7%, P = 0.01) and capsular invasion (vs. 4.9%, P = 0.004).

CONCLUSION

Overall, SPTs are associated with excellent survival results after surgical resection. Disease recurrence is extremely rare, and might occur if the primary tumor presents with either pancreatic parenchyma or capsule invasion. J. Surg. Oncol. 2016;114:597-601. © 2016 Wiley Periodicals, Inc.

Different prognostic roles of tumor suppressor gene BAP1 in cancer: A systematic review with meta-analysis

Biallelic inactivation of the tumor suppressor gene BRCA1-associated protein 1 (BAP1) has been demonstrated in several cancers, but its prognostic role has not been completely explained. We aimed to investigate the risk associated with loss of BAP1 (BAP1-) for all-cause mortality, cancer-specific mortality and recurrence of disease in subjects with cancer. PubMed and SCOPUS were searched from database inception until 09/15/2015 without language restrictions. Prospective studies reporting data on prognostic parameters in subjects with cancer, comparing participants with presence of BAP1 (BAP1+) vs. BAP1- were included. Data were summarized using risk ratios (RR) for number of deaths/recurrences and hazard ratios (HR) for time-dependent risk related to BAP1- adjusted for potential confounders. From 261 hits, 12 studies (including 13 cohorts) with 3,447 participants (BAP1-: n = 697; BAP1+: n = 2,750), with a median follow-up over 60 months, were meta-analyzed. Compared to BAP1+, BAP1- significantly increased all-cause mortality, cancer-specific mortality and risk of recurrence in all the tumor types analyzed, except for mesothelioma, in which the presence of BAP1 mutations correlates with a better prognosis. Furthermore, we demonstrated that BAP1 mutated colorectal and renal carcinomas are associated with high-tumor grading (P < 0.0001), and that BAP1 mutated is more common in women than in men (P < 0.0001). In conclusion, on the basis of our meta-analysis, we have demonstrated a peculiar role of BAP1 in influencing the prognosis in cancer. Thus, BAP1 could be considered as an important potential target for personalized medicine. © 2016 Wiley Periodicals, Inc.