Local Extension Research Articles

High-dimensional data clustering by using local affine/convex hulls

In this paper we propose a novel clustering algorithm that uses local affine/convex hulls for high-dimensional data clustering. In high-dimensional spaces, the sparse and irregular distributions make the nearest-neighbor distances unreliable (hole artifact), and this deteriorates the clustering performance. Therefore, there is a need to fill in these gaps between the nearest samples. To this end, we use local affine/convex hulls of the nearest neighbors of a given sample to fill in the holes, and this greatly improves the Euclidean distance metric and the clustering accuracy. The proposed method can also be seen as the local extension of the well-known iterative subspace clustering algorithms in which the entire cluster is approximated with a single linear/affine subspace. Experimental results show that the proposed method is efficient and it outperforms other subspace clustering algorithms on a wide range of datasets.

Improvement of economic and sustainability performance of agribusiness management using ecological technologies in Indonesia

Purpose The purpose of this paper is to evaluate the implications of and assess the economic and sustainable impact of environmentally friendly technological packages introduced into agribusiness players in the centre of chilli-producing regions of Indonesia. Design/methodology/approach This study used a theory of optimisation in production as a fundamental analysis. Producers are assumed to maximise profit by allocating rational amounts of inputs as the components of technological packages. A combination of qualitative and quantitative methods was used. The rate of technology adoption was evaluated, and agribusiness performance was measured using an economic advantage and technical efficiency. Data were compiled using group discussions and individual surveys. Findings The packages of technologies improved economic and sustainability performance of agribusiness resulting from efficient use of agrochemicals and water resource, and increase the production. Socio-economic and technical factors influenced performance farmers, as agribusiness players responded positively towards the ecological technology packages. Research limitations/implications The sustainability of agribusiness was indicated by the reduction in agrochemical use and by the efficient use of water irrigation. There are other measures of sustainability, which are beyond this study. Additional studies are expected to fill the gap. Practical implications Considerable potential exists for broad adoption of these technological packages in Indonesia if they are disseminated effectively and in a close partnership with local extension agencies, farmers’ organisations, local non-governmental organisations and private sectors. Originality/value This study provides a realistic representation of a current condition because this is an empirical study conducted at the grass-root level. Sustainability of agribusiness practices was achieved with ecological technological packages.

Farmer Centered Large Scale e-Surveillance and Control of Crop Pests in Kenya

With advancement of mobile technology and the property of mobile phones of being ubiquitous and pervasive, innovative applications in agriculture that are context specific and individualized to farmers’ needs can now be developed. This is because mobile phone based agricultural innovations are readily leveraged to provide farmers with information ranging from farm preparation and pre-harvest to post harvest and farm produce marketing. In this regard, this paper proposes a farmer centric pest e-surveillance solution framework, a digital platform that uses mobile devices, image processing and crowdsourcing to assist smallholder farmers in low income countries to effectively identify and control crop pest invasion, and to connect them with local agro-vet stores and extension service providers for assistance. This way, we can assist small holder farmers in rural Africa to learn about crop pests, to detect and respond to pest invasion, and to control the effects of such pest invasion by providing timely, accurate, relevant and readily consumable information in the local languages of the farmers. This also makes it easy to perform large-scale pest surveillance in the rural farming community.

Clinical Presentation and Management of Brain Metastasis in a Sample of Iraqi Patients

Brain metastases are neoplasms that originate in tissues outside the brain and spread secondarily to involve the brain [1] This may result either from direct local extension of the primary growth, or from blood born metastases [2]. The intracranial compartment is a common site of metastatic cancer. Between 20 and 40% of patients with systemic cancer developed brain metastasis. Such metastasis can be extra axial in nature (e.g. involving the dura and subdural space, or leptomeninges and subarchnoid space), but most commonly they occur within the brain parenchyma [3].

P4656Short- and long-term evaluation of safety of cardiac sarcomas radiotherapy

Abstract Background Primary cardiac sarcomas (PCS) have a dismal prognosis (a reported median survival of 17 months). Complete surgical resection is the mainstay of treatment, but the resection may be incomplete or impossible because of the local extension. Multimodal treatment (MMT) with chemotherapy and radiotherapy (RT) is widely used in soft tissue sarcomas of the extremities, improving survival, and could be considered for PCS. A consequence of the inclusion of the heart in a radiation field, is acute and chronic radiation-induced heart disease (RIHD). New RT techniques, as Intensity Modulated Radiotherapy (IMRT) reduce the risk, focusing the radiation burden to the target neoplasm and limiting the involvement of the cardiac structures. Nevertheless, RT is rarely used in PCS, because the target lesion is inside the heart, and the heart's movement make difficult to avoid the irradiation of the surrounding structures. Purpose Our aim was to report the short and long term clinical and echocardiographic changes in patients (pts) with cardiac sarcomas treated with IMRT. Methods Amongst a group of 33 with PCS seen in our hospitals, we reviewed the data of 20 pts (12 males, 8 females) with PCS treated with local RT. The tumors were left-sided in 10 pts, right-sided in 8 and involved both right and left chambers in 2; fifteen patients had received also anthracyclines chemotherapy (CT). For every patient, we reviewed the clinical data and the echocardiograms performed (as for protocol) before and after CT, before starting RT, weekly during RT and at follow-up (FU), performed every 3 months for 2 years, every 6 months for 3 more years, then yearly. The mean age at diagnosis was 48 years (range 22–72). The FU lasted 2 to 131 months (mean 31, median 14). Five pts are alive 29–85 months (mean 57), after ending therapies, the others died of non-cardiac causes. Results At the end of RT 3 pts had atrial fibrillation (AF), which was cardioverted with Amiodarone, and one had acute pericarditis, treated with non-steroidal anti-inflammatory drugs for one week. Long-term therapy was not needed. The left ventricular ejection fraction (LVEF) was 52% to 70%, decreased by −1% to −10% in 10 pts. At last FU, LVEF ranged from 52 to 75%; it decreased (compared to baseline) by >11% in 1 pt only; global longitudinal LV strain (GLS), available in 8 pts only, was −17%. Amongst the pts with IMRT on the right heart, right ventricular function (evaluated by tricuspid annulus excursion, and right ventricular area shortening fraction) was within normal limits in all both at short and long term FU. There were no cases of constrictive pericarditis or of valvular disease. Conclusion In our experience IMRT for heart sarcomas seems to be relatively safe using modern RT techniques, without evident RIHD at long term follow-up. Larger studies are necessary to further evaluate the safety of RT in the multimodal treatment of cardiac sarcomas.

OSTEOSARCOMA IN PAGET DISEASE OF BONE

Background Paget disease of bone (PDB) is a disorder of bone metabolism that involves osteoclasts. Osteosarcoma arising in Paget disease is a rare complication of PDB occurring in less than 1% of all osteosarcomas. The aim of this case report is to describe different imaging features of osteosarcomas arising in PDB and its progression. Clinical and Radiographic Findings A 72-year-old female with known arthritis and PDB presented to the emergency room with a 1-week headache and right temporal/parietal skull swelling. The erythrocyte sedimentation rate (ESR) and serum alkaline phosphatase (ALK) were elevated. Planar radiographs of the skull exhibited mixed sclerotic and radiolucent lesions throughout, giving a cottonwool appearance. Multidetector computed tomography (MDCT) of the head showed peripheral enhancement, a partially calcified right temporal region mass, and expansion of the underlying calvarium with a periosteal reaction. Intracranial extension was clear on magnetic resonance imaging (MRI). Furthermore, positron emission tomography/computed tomography (PET/CT) revealed increased fluorodeoxyglucose (FDG) avidity in the solitary right temporal/parietal lesion. Biopsy revealed osteosarcoma with chondroblastic features arising in PDB. The patient underwent right craniectomy and resection of the tumor. Six weeks later, gross recurrent disease at the resection site was found on a head MDCT that demonstrated soft tissue density underlying the cranioplasty with a significant amount of vasogenic edema involving the temporal/frontal lobe. The patient underwent right decompressive and epidural tumor resection. A day later, she was pronounced brain dead. Discussion/Conclusions PDB is often diagnosed through incidental findings in a regular blood chemistry panel, particularly ALK, or through imaging done for another reason. The planar radiograph gives the best clue to the presence of PDB. The MDCT is mandatory for better outcomes in treatment of osteosarcoma, whereas MRI is best for depicting local intracranial extension. PET identifies the region of a tumor through FDG increase. Lastly, biopsy is necessary for confirming the tumor. Paget disease of bone (PDB) is a disorder of bone metabolism that involves osteoclasts. Osteosarcoma arising in Paget disease is a rare complication of PDB occurring in less than 1% of all osteosarcomas. The aim of this case report is to describe different imaging features of osteosarcomas arising in PDB and its progression. A 72-year-old female with known arthritis and PDB presented to the emergency room with a 1-week headache and right temporal/parietal skull swelling. The erythrocyte sedimentation rate (ESR) and serum alkaline phosphatase (ALK) were elevated. Planar radiographs of the skull exhibited mixed sclerotic and radiolucent lesions throughout, giving a cottonwool appearance. Multidetector computed tomography (MDCT) of the head showed peripheral enhancement, a partially calcified right temporal region mass, and expansion of the underlying calvarium with a periosteal reaction. Intracranial extension was clear on magnetic resonance imaging (MRI). Furthermore, positron emission tomography/computed tomography (PET/CT) revealed increased fluorodeoxyglucose (FDG) avidity in the solitary right temporal/parietal lesion. Biopsy revealed osteosarcoma with chondroblastic features arising in PDB. The patient underwent right craniectomy and resection of the tumor. Six weeks later, gross recurrent disease at the resection site was found on a head MDCT that demonstrated soft tissue density underlying the cranioplasty with a significant amount of vasogenic edema involving the temporal/frontal lobe. The patient underwent right decompressive and epidural tumor resection. A day later, she was pronounced brain dead. PDB is often diagnosed through incidental findings in a regular blood chemistry panel, particularly ALK, or through imaging done for another reason. The planar radiograph gives the best clue to the presence of PDB. The MDCT is mandatory for better outcomes in treatment of osteosarcoma, whereas MRI is best for depicting local intracranial extension. PET identifies the region of a tumor through FDG increase. Lastly, biopsy is necessary for confirming the tumor.

Fracture systems and petrophysical properties of tight sandstone undergoing regional folding: A case study of the Cretaceous reservoirs in the Kuqa foreland thrust belt, Tarim Basin

Abstract The Kuqa foreland thrust belt of the Tarim Basin hosts a prolific hydrocarbon system. The main reservoirs are characterized by tight sandstone with low-porosity and ultra-low permeability, buried presently at more than 5000 m depth. Natural fracture systems have a significant impact on reservoir performance, and it may form paths for fluid flow in tight sandstone reservoirs, and therefore plays an essential role in controlling high production rates. With the aim of analyzing the distribution of favorable reservoir, we studied subsurface fracture patterns and petrophysical properties of the Bashijiqike Formation with data collected from Dabei structure and Keshen structure. We document the presence of four fracture systems whose distribution is related to far-field stress, thrusting and folding. In the Keshen anticlines, higher fracture intensities are observed in the limbs, with principal east-west (hinge-parallel fracture system) direction. The hinge-parallel fracture system includes a moderate-dipping fracture set and a vertical fracture set. Crosscutting relationships stress field inversion and fracture surface textures suggest that the moderate-dipping fracture set consists of shear fractures and can be explained by intra-layer shear caused by thrusting. The vertical fracture set may be formed due to the local outer arc extension during folding. The oblique fracture system shows scattering in strike, and is supposed to be related to a shear event of locally left-lateral strike-slip. Whereas, in the Dabei anticlines, the major system is hinge-perpendicular fracture system (NW-SE), showing a trending of increasing fracture intensity from limbs to hinge. The hinge-perpendicular fractures system in the Dabei anticlines consist of shear fractures and tension fractures. Stress inversion result shows it corresponds to northwest-southeast orientation compression stage. Besides, we analyzed petrophysical properties include porosity, permeability, Young's module, Poisson ratio and compressive strength of the Bashijiqike Formation concerning their structural position within folds. It indicates that the highest porosity and permeability are associated with dissolution and fracturing. The compressive strength of different structural positions also restrict the variations of mechanical properties of rocks. The best reservoir quality is suggested in the hinge zone and areas close to thrust. The findings have given maybe helpful for providing favorable reservoir targets for prospecting in the compressional basin.

Central Nervous System Infections Due to Aspergillus and Other Hyaline Molds.

Central nervous system infections due to Aspergillus spp and other hyaline molds such as Fusarium and Scedosporium spp are rare but fatal conditions. Invasion of the central nervous system (CNS) tends to occur as a result of hematogenous dissemination among immunocompromised patients, and by local extension or direct inoculation secondary to trauma in immunocompetent hosts. Efforts should be directed to confirm the diagnosis by image-guided stereotactic brain biopsy when feasible. Non-culture methods could be useful to support the diagnosis, but they have not been validated to be performed in cerebral spinal fluid. Treatment of these infections is challenging given the variable susceptibility profile of these pathogens and the penetration of antifungal agents into the brain.

Urgently strategic insights to resolve the Nigerian food security crisis

The food security crisis is a serious worldwide predicament in developing countries but it is a relatively larger problem in Nigeria. We argued there was no solution for the Nigerian food security crisis because researchers had not customized theoretical models with data-driven priorities grounded on local agriculture subject matter expert knowledge. We collected data from local agriculture extension workers who had specialized knowledge of the problems. We applied the consensual qualitative research method with embedded nominal brainstorming and multiple correspondence statistical techniques at the group level of analysis to develop a proposed solution. Our final model highlighted strategically urgent ideas to increase agriculture productivity and appease the most severe constraints in rural Nigeria. The results extended what was already published in the literature and should generalize to rural farmers in Nigeria as well as to government policymakers in developing countries around the world.

Base‐salt relief controls salt‐related deformation in the Outer Kwanza Basin, offshore Angola

AbstractSalt‐influenced passive margins are widespread and commonly hydrocarbon‐rich. However, they can be structurally complex, with their kinematic development being poorly understood. Classic models of salt tectonics divide such margins into updip extensional, mid‐slope translational and downdip contractional kinematic domains. Furthermore the faults, folds, and salt walls associated with each kinematic domain are typically assumed to form perpendicular to the maximum principal stress, which in gravitationally driven systems means broadly perpendicular to base‐salt dip. We use high‐resolution 3D seismic reflection data from the Outer Kwanza Basin, offshore Angola to show that these models cannot explain the diversity of salt structures developing on passive margins, especially those defined by considerable relief on the base‐of‐salt surface. Overburden seismic‐stratigraphic patterns record the basinward translation and rotation, allowing us to reconstruct the origin and evolution of the salt structures. We show structures in the transitional domain of the Outer Kwanza Basin display three dominant trends, each characterised by different structural styles: (a) salt walls perpendicular to the overall base‐salt dip, (b) salt walls parallel to the base‐salt dip and (c) salt walls oblique to the base‐salt dip. We show that each set of walls has a unique history, with synchronous phases of extension and compression occurring in adjacent structures despite their close spatial relationship. Our analysis suggests that, in the Outer Kwanza Basin, the structural evolution of the salt and overburden is predominantly controlled by translation over relief on the base‐salt surface formed above fault scarps associated with a preceding phase of rifting. Changes in the downdip volumetric flux and velocity of the salt over topographic features can cause local extension or contraction of the salt and its overburden, associated with local acceleration or deceleration of the salt, respectively. This interaction with base‐salt relief creates locally variable stress fields that deform the salt and its overburden, overprinting the broader, margin‐scale salt tectonics typically associated with gravity gliding and spreading.

Imaging characteristics of nasopharyngeal carcinoma for predicting distant metastasis

To determine the imaging characteristics of nasopharyngeal carcinoma (NPC) that may be associated with increased risk of distant metastasis. A total 164 patients with NPC were reviewed retrospectively. Patients were divided into the metastatic group (n=110) or the non-metastatic group (n=54). Non-metastatic was defined as no evidence of distant metastasis during at least 5 years of follow-up. Pretreatment images of the primary tumour and nodal involvement were analysed. Statistical analyses were performed to identify the factors that may predict distant metastasis. The statistically significant sites of tumour extension in the metastatic group included: skull base bone (p<0.001), cervical spine (C-spine; p=0.012), parapharyngeal space (p=0.003), pterygopalatine fossae (PPF; p=0.004), prevertebral space (p<0.001), masticator space (p=0.006), carotid space (p=0.001), and intracranial extension (p=0.004). Statistically significant nodal involvement included bilateral involvement (p=0.04), size 3-6 cm (p=0.011), >10 pathological nodes (p<0.001), level IB (p=0.013), IIB (p=0.011), III (p=0.001), IV (p<0.001), VB (p=0.001), and supraclavicular (p=0.003) and intraparotid nodes (p=0.004). The mean number of significant involvement factors was significantly higher in the metastatic group (3.46±2.24 tumour extension sites and 5.04±2.51 nodal involvement factors) than in the non-metastatic group (p<0.001). NPC patients with local extension at more than three sites and with more than five nodal involvement factors should be screened for distant metastasis.

Evaluación técnica de la agregación de valor a partir de variedades de cebolla (Allium cepa) cultivadas al norte de la Región Central Oriental de Costa Rica

El sector cebollero costarricense es dinámico y cuenta con una institucionalidad que respalda las acciones de investigación y extensión, como el Programa Nacional de Cebolla del Ministerio de Agricultura y Ganadería-MAG, las Agencias de Extensión Agropecuaria locales, y el Programa de Investigación y Transferencia de Tecnología Agropecuaria-PITTA Cebolla. Sin embargo, la comercialización en fresco de la cebolla enfrenta dificultades, por lo que este proyecto tuvo por objetivo “Evaluar el proceso de agregación de valor a variedades de cebolla (Allium cepa) cultivadas en zona Norte de la Región Central Oriental (al norte de Cartago). Se consideraron los materiales E515, Predator y Alvara, valorando dos variables principales para el análisis comparativo a partir de pruebas de valor agregado, considerando: tiempo de ejecución del proceso agroindustrial y rendimiento de producción. Las variedades Predator y E515 usualmente mostraron los rendimientos más altos y los menores tiempos de elaboración según el producto de valor agregado del que se tratara. Los resultados fueron transferidos a los beneficiarios en un taller teórico y tres sesiones prácticas en la Planta Piloto Agroindustrial del Instituto Tecnológico de Costa Rica (TEC). Se recomienda ahondar en investigaciones para validar los resultados hallados y se sugieren estudios de factibilidad específicos en el caso de desear incursionar en emprendimientos de este tipo.

Comparison of the Diagnostic Ability of Endoscopic Ultrasonography and Abdominopelvic Computed Tomography in the Diagnosis of Gastric Subepithelial Tumors.

Background/AimsEndoscopic ultrasonography (EUS) is the most efficient imaging modality for gastric subepithelial tumors (SETs). However, abdominopelvic computed tomography (APCT) has other advantages in evaluating the characteristics, local extension, or invasion of SETs to adjacent organs. This study aimed to compare the diagnostic ability of EUS and APCT based on surgical histopathology results. MethodsWe retrospectively reviewed data from 53 patients who underwent both EUS and APCT before laparoscopic wedge resection for gastric SETs from January 2010 to December 2017 at a single institution. On the basis of histopathology results, we assessed the diagnostic ability of the 2 tests. ResultsThe overall accuracy of EUS and APCT was 64.2% and 50.9%, respectively. In particular, the accuracy of EUS vs. APCT for the diagnosis of gastrointestinal stromal tumors (GISTs), leiomyomas, and ectopic pancreas was 83.9% vs. 74.2%, 37.5% vs. 0.0%, and 57.1% vs. 14.3%, respectively. Most of the incorrect diagnoses with EUS involved hypoechoic lesions originating in the fourth echolayer, with the most common misdiagnosed lesions being GISTs mistaken for leiomyomas and vice versa. ConclusionsAPCT showed a lower overall accuracy than EUS; however, APCT remains a useful modality for malignant/potentially malignant gastric SETs.

Constraining mountain front tectonic activity in extensional setting from geomorphology and Quaternary stratigraphy: A case study from the Matese ridge, southern Apennines

Rugged peaks, large intermontane basins and frequent seismicity all characterize the active extensional tectonic setting of the southern Apennines. The Matese ridge typifies the active tectonic setting of the southern Apennines with steep carbonate mountain fronts and large depositional centres. Moderate to high magnitude earthquakes have affected the northern, western and eastern sectors of the Matese ridge in historical times. However, the seismogenic potential of the extensional fault system bounding the southern Matese mountain front has not been fully assessed to date. To unravel the active tectonic setting of the southern Matese mountain front, we have carried out a comprehensive geomorphological and tectonic-geomorphology investigation of the mountain front and its piedmont and have constrained results through chronological (i.e., tephrostratigraphical and 40Ar/39Ar) and structural data.Our study highlights that in the last ∼600 ka, activity along E-W trending normal faults has identified a locus of higher slip rate tectonic activity in the central part of the analysed mountain front. These active E-W-striking normal faults are inherited, reactivated structures, which have interacted with newly formed NW-SE-striking normal faults during NE-SW extension active on the regional scale, causing fault bending and local extension to be oriented N-S. Consequently, lower slip rates have been recorded along the NW-SE-striking normal faults at the north-western and south-eastern tips of the southern Matese front. The long-term displacement rate of the fault system at the boundary of the central part of the southern Matese front is consistent with mean values of displacement of faults that, in the southern Apennines, show evidence of activity during the late Quaternary. Despite strong historical seismicity clustering primarily around the study area, our data highlight that it cannot be ruled out that moderate to high magnitude seismicity could affect the southern Matese mountain front.Our case study represents an example of the possible modes of formation and evolution of mountain front-basin systems in extensional setting, and shows how the combination of different data sets allows unravelling the interaction between tectonic, erosional and sedimentary processes, which lead to landscape evolution of active mountain belts.

Statistical methodology for on-site wind resource and power potential assessment under current and future climate conditions: a case study of Suriname

The feasibility and long term sustainability of proposed projects for wind energy production strongly depend on the availability of wind resources. This availability is assessed by means of local wind speed statistics. Under climate change, the future (long term) wind resource availability is, however, highly uncertain. This research proposes a methodology for on-site wind resource assessment in future (climate change) perspective based on stochastic modeling, observed data and the latest generation of climate model results for future projections. Statistical downscaling and bias correction methods, i.e., the Quantile Perturbation Method and Quantile Matching, are applied to enable local scale assessments. It requires observed data for extended periods to facilitate climate change signal assessments and associated future projections. Two types of data sets are considered for observed data, i.e., on-site (local) measurements and reanalysis data. Two stochastic modeling approaches were adopted for the local observations data extension, i.e., a Markov and Weibull model, allowing for a sensitivity assessment. The methodology has been applied to a potential wind site in Suriname. Results reveal significant changes in wind power potential for the end of the century (2070–2100), ranging from − 27 to 89%. Analysis of the extreme conditions reveals an extended range, from − 65 to 282%.

Vierbein interactions with antisymmetric components

In this work we propose a new gravitational setup formulated in terms of two interacting vierbein fields. The theory is the fully diffeomorphism and local Lorentz invariant extension of a previous construction which involved a fixed reference vierbein. Certain vierbein components can be shifted by local Lorentz transformations and do not enter the associated metric tensors. We parameterize these components by an antisymmetric tensor field and give them a kinetic term in the action, thereby promoting them to dynamical variables. In addition, the action contains two Einstein-Hilbert terms and an interaction potential whose form is inspired by ghost-free massive gravity and bimetric theory. The resulting theory describes the interactions of a massless spin-2, a massive spin-2 and an antisymmetric tensor field. It can be generalized to the case of multiple massive spin-2 fields and multiple antisymmetric tensor fields. The absence of additional and potentially pathological degrees of freedom is verified in an ADM analysis. However, the antisymmetric tensor fluctuation around the maximally symmetric background solution has a tachyonic mass pole.

Dedifferentiated liposarcoma of the thyroid gland: A case report.

Liposarcoma is one of the most common soft tissue tumors that affect adults. Liposarcoma is typically identified in the retroperitoneum, trunk and extremities as a slow-growing mass, yet is rare in the thyroid gland. Herein, we report a case of dedifferentiated liposarcoma that developed in the thyroid gland, and performed a literature review. A 66-year-old male with a history of well-differentiated liposarcoma in the thymus presented with a rapidly enlarging mass in the thyroid gland. Malignancy was suspected due to the local extension of the tumor, and complete resection of the tumor was achieved. Tissue diagnosis from the tumor following surgery revealed that dedifferentiated liposarcoma, and tumor progression was difficult to control with adjuvant radiation and chemotherapy. This is, to the best of our knowledge, the first case to report dedifferentiated liposarcoma in the thyroid gland, and the difficulty in initial diagnosis as well as the aggressive features of dedifferentiated liposarcoma are highlighted.

The Role of Imaging Techniques in Diagnosing Pancreatic Cancer

Imaging techniques play an essential role in the diagnosis, staging and establishing the treatment protocols in pancreatic cancer. Our proposed study explores and improves recent discoveries in the field of pancreatic cancer, especially relying on complex imaging techniques such as Computer Tomography (CT), Nuclear Magnetic Resonance (MR 3T), Ultrasonography (US) and Endoscopic Ultrasonography (EUS). In the case of pancreatic tumors, regardless of their origin, imaging exams also allow the evaluation of local and distant extension, with important prognostic and treatment ramifications. CT exams alongside RM and EUS offer a highly sensible and specific diagnosis of pancreatic tumors, with the added advantage of concomitant evaluation of adjacent parenchymatous abdominal organs.

68Ga-PSMA PET/CT: Does it predict adverse pathology findings at radical prostatectomy?

IntroductionData on the accuracy of 68Ga-PSMA positron emission tomography/computed tomography (PET/CT) in patients with intermediate/high-risk prostate cancer are being accumulated. Its role in assessing the extent of local disease has not been fully elaborated. AimTo determine the performance characteristics of 68Ga-PSMA PET/CT in identifying local disease extension in patients with intermediate/high risk prostate cancer. Methods68Ga-PSMA PET/CT studies of 61 consecutive patients with intermediate/high-risk prostate cancer who underwent radical prostatectomy were reviewed by nuclear medicine specialists. Tumor location, extraprostatic extension (EPE), seminal vesicle invasion (SVI), and lymph nodes involvement (LNI) were compared to pathological findings. The incremental value of 68Ga-PSMA PET/CT to established nomograms was determined. ResultsTwo patients without pathologic uptake of 68Ga-PSMA were excluded. Seventeen patients were diagnosed with EPE (29%), 12(20%) had SVI and 3(5%) LNI. The concordance between tumor location and 68Ga-PSMA PET/CT findings was 48%, and EPE was not indicated by PET in any of the patients. The sensitivity, specificity, positive, and negative predictive value for SVI were 58%, 96%, 78%, 90%, respectively (area under the receiver operating characteristic curve = 0.77) and for LNI 67%, 98%, 67%, 98%, respectively (area under the receiver operating characteristic curve = 0.82). Incorporating imaging findings into the MSKCC-SVI nomogram enhanced the diagnostic accuracy from 0.84 to 0.95 (Integrated Discrimination Increment 0.24, P = 0.004). ConclusionIn patients with intermediate/high-risk prostate cancer, 68Ga-PSMA PET/CT provides information regarding intraprostatic tumor location, SVI and LNI but has no role in assessment for EPE. This information might be useful for pretreatment counseling, decision-making and possibly preoperative planning.

Neuroblastoma Characteristics and Embryonic Origin of The Primary Lesion Site: A SEER Study

Background: Neuroblastoma, one of the most prevalent infant malignancies, is heterogeneous and easily spreads into other organs causing life-threatening consequences. Different characters of organs (such as the germ layers where the organs derived from) exert different growth microenvironments and potentially influence the behavior of metastatic neuroblastoma cells and the prognosis of patients. However, limited information is been known about this in neuroblastoma. Objectives: To compare characteristics of neuroblastoma, primarily originating from the same germ layer (the seeds), in different tissues (microenvironment) derived from different germ layers. Methods: We performed retrospective analysis of SEER (Surveillance, Epidemiology, and End Results) data (1973 - 2014), patients with malignant neuroblastoma were grouped based on the primary lesion site (mesoderm-, ectoderm- or endoderm-derived tissue). Baseline demographic and clinical characteristics were compared between groups. Due to difficulties of processing incomplete SEER data, therapeutic method and survival rates were analyzed using cases from another SEER database (2000 - 2014). Results: The analysis included 3701 patients: 1970 (53.2%) in the mesoderm group, 1017 (27.5%) in the ectoderm group and 714 (19.3%) in the endoderm group. Tumor histology differed between groups (P < 0.01): the ectoderm group had mostly neuroblastoma (79.2%), as did the mesoderm group (71.1%), whereas the endoderm group contained mainly olfactory neuroblastoma (94.7%). The tumors (mean size: 69.14 ± 58.37 mm) were most commonly poorly differentiated with local extension, although lymph node invasion and distant metastasis occurred in a minority of cases. Compared with the other groups, the endoderm group had smaller (43.89 ± 20.84 mm) and better-differentiated tumors and a lower prevalence of lymph node invasion and metastasis (P < 0.05). Despite this, overall survival was poorest for the endoderm group (P < 0.05). Radiotherapy improved overall survival in the endoderm and ectoderm groups but worsened overall survival in the mesoderm group (P < 0.05). Conclusions: Malignant neuroblastoma characteristics may be influenced by the tumor microenvironment. In the youngest patients, decision-making regarding the best choice of therapy should be delayed until accurate risk stratification is possible.