Endoscopic ultrasound‐guided fine needle aspiration of the pancreas: cytomorphological evaluation with emphasis on adequacy assessment,diagnostic criteria and contamination from the gastrointestinal tract1

Objective: Endoscopic ultrasound (EUS)‐guided fine needle aspiration (FNA) has been proved to be safe, efficient and reliable in the diagnosis of pancreatic lesions. This study evaluated specimen adequacy, diagnostic criteria of various pancreatic neoplasms and contamination from the gastrointestinal (GI) tract. Methods: EUS‐guided FNA of the pancreas and subsequent surgical resections performed at the University of California Irvine Medical Center during February 1996–October 2000 were retrospectively selected. Modified Papanicolaou staining method was used for immediate evaluation and cell block prepared. Results: A total of 267 cases were available for review, including 147 (55.1%) positive/suspicious, 10 (3.7%) atypical, 96 (36.0%) negative and 14 (5.2%) unsatisfactory cases. Eighty‐six (58.5%) positive/suspicious cases had histological confirmation and 12 (8.3%) had lymph node or distant metastases by cytology. Three atypical, two negative, and two unsatisfactory cases proved to have adenocarcinoma. Contamination from duodenum, stomach or pancreas was found in 77 positive/suspicious, three atypical and 90 negative cases. The sensitivity, specificity, diagnostic accuracy, positive and negative predictive values were 94.6%, 100%, 95.6%, 100%, 82% respectively. Conclusions: EUS FNA is efficient and accurate in the diagnosis of pancreatic neoplasms in adequate samples. Contamination from the GI tract should be well recognized to avoid misinterpretation.     

EUS图像胰腺癌分类中粒子光斑的去除

已有基于图像纹理特征对胰腺超声内镜图像进行是否为癌症的分类方法.放射性粒子植入治疗是一种较常用的姑息治疗方法.治疗后的图像中由植入粒子所产生的光斑对分类的结果有一定的影响.通过使用改进的中值滤波方法去除光斑后分类结果的准确性有了一定的提高.     

Aphanomyces invadans,the causal agent of Epizootic Ulcerative Syndrome,is a global threat to wild and farmed fish

Aphanomyces invadans is a eukaryotic pathogen and the causative agent of Epizootic Ulcerative Syndrome (EUS) in fish and is responsible for mortalities of up to 100% in aquaculture. A. invadans was first discovered in Japan in 1971, and since then it has been found in Australia, North America, Southern African countries and Asia. Methods for the correct identification of A. invadans are well established now and involve PCR-based detection and microscopy. However, the pathogenesis of A. invadans is poorly understood. Environmental stress (mainly temperature) and the associated immunocompromised fish seem to induce infections of A. invadans and outbreaks of EUS. Understanding the process of infection in more depth is fundamental for the discovery of novel effective treatments to combat the disease. In this review, we discuss morphological characteristics of A. invadans and its pathogenicity as well as various approaches of treatment.     

Endoscopic ultrasound-guided tissue sampling by combined fine needle aspiration and trucut needle biopsy: a prospective study

BACKGROUND AND AIMS: Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has a diagnostic accuracy of 70-90%, depending on the site under evaluation. In order to improve EUS-guided tissue sampling a novel 19-gauge trucut-type needle has been designed to obtain core biopsies during EUS. We prospectively evaluated the safety and accuracy of EUS-FNA alone versus combined EUS-FNA and trucut needle biopsy (TNB) in patients referred to our Unit over a 3-year period. PATIENTS AND METHODS: A total of 159 patients underwent EUS-FNA alone (lesions<2 cm) or the combination of both sampling modalities (lesions>or=2 cm). The adequacy of sampling, sensitivity, specificity and overall accuracies of EUS-FNA or EUS-TNB alone and combined EUS-FNA/TNB were determined. RESULTS: Adequate samples were obtained by EUS-FNA, EUS-TNB and EUS-FNA/TNB in 91%, 88% and 97% of patients, respectively. From the pancreas (n=83), adequate samples were obtained by FNA in 94% and by TNB in 81%, compared with 87% and 92% from non-pancreatic sites (n=76), respectively. The combination of both techniques resulted in more adequate samples from non-pancreatic cases than EUS-FNA alone (P=0.044). The specificity was 100%. Overall accuracy for EUS-FNA alone was 77%, for EUS-TNB alone 73% and for EUS-FNA/TNB 91% (P=0.008). For pancreatic sampling, the accuracy of EUS-FNA alone was 77%, for EUS-TNB alone 56% and for EUS-FNA/TNB 83%. For non-pancreatic sampling, the accuracy for EUS-FNA alone was 78%, for EUS-TNB alone 83% and for EUS-FNA/TNB 95% (P=0.006). The complication rate was 0.6%. CONCLUSIONS: Combined EUS-FNA/TNB for lesions>or=2 cm improves adequacy of sampling and diagnostic accuracy compared with either technique alone and is safe.     

Molecular diagnostics of non-small cell lung cancer using mediastinal lymph nodes sampled by endoscopic ultrasound-guided needle aspiration

Non-small cell lung cancer is a common cancer with significant mortality. Accurate and early staging of this cancer has a significant impact on outcome. Endoscopic ultrasound-guided fine needle aspiration of involved mediastinal lymph nodes is critical for staging. Several molecular markers have been identified recently in association with non-small cell carcinoma of the lung that are promising to make early detection of metastatic disease more reliable.     

Endoscopic ultrasound-guided FNA biopsy of bile duct and gallbladder: analysis of 53 cases

OBJECTIVE: Endoscopic retrograde cholangiopancreaticography (ERCP)-guided brushing has been the standard of practice for surveillance and detection of carcinoma in the biliary tree. Few studies have evaluated the role of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in diagnosing clinically suspected cholangiocarcinoma. The role of this method in diagnosing clinically suspected gallbladder malignancies has not been extensively evaluated in the USA. This study investigates the role of EUS-FNA in the diagnosis of clinically suspected biliary tree and gallbladder malignancies in a large patient series. METHODS: EUS-FNAs were obtained from 46 bile duct and seven gallbladder lesions. On-site rapid interpretation was provided using air-dried Diff Quik stained smears. In addition, alcohol fixed Papanicoloau stained smears and Thin Prep preparations (Cytye Corp., Marlborough, MA, USA) were evaluated before providing a final cytological diagnosis. Tissue biopsies and/or clinical follow-up were used as the standards to determine operating characteristics for EUS-FNA. RESULTS: The mean ages for bile duct and gallbladder lesions were 66 years (range: 37-84 years), and 69 years (range 49-86 years), respectively. All cases diagnosed as suspicious/malignant on preliminary evaluation were confirmed on final cytological interpretation (27/27). The operating characteristics show that EUS-FNA is highly specific (100%) with sensitivity rates of 87% and 80% from clinically suspected malignancies of biliary tract and gallbladder, respectively. Sampling error in three cases and associated acute inflammation in two cases resulted in false-negative diagnoses. CONCLUSIONS: EUS-FNA of biliary tree and gallbladder carcinoma is highly specific and should be considered for evaluation of clinically suspicious lesions. Marked inflammation may result in false-negative diagnoses.     

Endoscopic ultrasound-guided fine needle aspiration cytology of pancreatic neuroendocrine tumours: cytomorphological and immunocytochemical evaluation

OBJECTIVES: Endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) is increasingly used in preoperative localization and diagnosis of pancreatic neoplasms including neuroendocrine tumours (NETs). The objective of the present study was to identify the cytological features of pancreatic NETs obtained by EUS-FNA. METHODS: The study group consisted of nine cases of pancreatic tumours correctly diagnosed or strongly suggestive of NETs based on EUS-FNA. Cytological smears were retrospectively reviewed. The clinical data and immunocytochemical stains applied to the cell block preparations were also reviewed and examined. RESULTS: All cases except one showed characteristic cytomorphological features sufficient for their recognition and separation from pancreatic adenocarcinoma and other lesions. The most helpful cytological features that facilitated the cytological diagnosis of NET were a richly cellular aspirate with a monotonous, poorly cohesive population of small cells with a speckled or dusty chromatin pattern and plasmacytoid morphology. The neuroendocrine differentiation of these tumours was further confirmed by immunocytochemistry. CONCLUSION: EUS-FNA is a valuable method in the recognition of pancreatic NETs. By adherence to the characteristic cytomorphological criteria of pancreatic NET together with collection of suitable material for ancillary immunocytochemical stains, cytopathologists could reach a correct diagnosis in most instances.     

超声内镜与胃镜在胃间质瘤临床诊断的对比分析

目的探讨超声内镜和胃镜在胃间质瘤的临床诊断价值。方法选取我院2013年1月~2014年11月初步诊断为胃间质瘤患者350例,其中行超声内镜检查175例,行胃镜检查175例,两组均行镜下病理活检,并比较两组检查结果的阳性率与病理结果之间的诊断符合率。结果超声内镜诊断阳性率为100%(175/175),胃镜诊断阳性率为97.14%(170/175),与病理结果的符合率为超声内镜的诊断符合率97.14%(170/175),高于胃镜诊断符合率的94.29%(165/175),但两者差异无统计学意义(P0.05)。结论超声内镜及胃镜诊断胃间质瘤各有特点,超声内镜诊断率高可作为胃间质瘤的术前首选检查。     

胰腺内镜超声图像纹理特征提取与分类研究

提出了胰腺内镜超声图像的纹理特征提取与分类方法,可应用于胰腺癌内镜超声图像的计算机辅助诊断。对胰腺内镜超声图像采用数字图像处理算法提取9大类共69个纹理特征。使用类间距作为可分性判据,实现特征的初步筛选,之后使用顺序前进搜索算法进一步筛选特征,并由支撑向量机实现分类。对216例病例随机选取训练集和测试集,通过多次随机实验表明。本文提出的算法实现了较高的分类准确率,为胰腺癌的临床诊断提供有价值的参考意见。     

Impact of cytopathologist expert on diagnosis and treatment of pancreatic lesions in current clinical practice. A series of 106 endoscopic ultrasound-guided fine needle aspirations

OBJECTIVES: To evaluate the role of a cytopathologist expert in interpreting difficult pancreatic endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in terms of impact on diagnostic yield and therapy in current clinical practice. METHODS: Retrospective study of 106 EUS-FNA performed between January 2002 and September 2004. Forty-seven cases of difficult interpretation by the local cytopathologist were mailed to an expert cytopathologist. The final diagnosis was established by histology obtained by either surgery (n=30), non-equivocal FNA (n=40) or core (n=8) biopsies, or by a mean follow-up of 14 months (n=28). RESULTS: EUS-FNA involved 68 solid lesions (SL). Specimens collected were adequate in 63%. The overall sensitivity of EUS-FNA for the diagnosis of malignancy of SL was 88% versus 72% for local cytopathologist and 89% for expert. EUS-FNA with the reevaluation by expert of 39 SL gave a therapeutic impact in 47% of SL. Thirty-eight cystic lesions (CL) were evaluated. Specimens collected were adequate for cytology in 84% of cases and for biochemistry in 79%. The sensitivity of imaging+EUS-FNA+/-biochemistry for the diagnosis of a surgical CL was 58% with a therapeutic impact in 39.5%. CONCLUSION: Pancreatic EUS-FNA is an easy technique for experienced endosonographers, which can be safely performed on an outpatient basis. The possibility of mailing difficult cases to an expert cytopathologist increases the diagnostic yield. In these circumstances, EUS-FNA has a therapeutic impact in current practice in nearly one out of two pancreatic lesions.     

Clinical application of 20 MHz endosonography and anti-Helicobacter pylori immunoblots to predict regression of low-grade gastric MALToma by H. pylori eradication

Aim. We tested whether serial 20 MHz endosonography (EUS) and anti‐Helicobacter pylori immunoblots can predict the complete regression of gastric MALToma by H. pylori eradication. Methods. The serums of 17 MALToma patients, including 15 with low grade and two with high grade, were collected before therapy. Fifteen patients with low‐grade MALToma and 18 nonMALToma patients, all infected with H. pylori, have been followed with serum sampling, endoscopy, and EUS on enrollment, on the 2nd, 6th, and 12th months after anti‐H. pylori therapy. All sera were tested for anti‐H. pylori immunoblots, including 19.5, 26.5, 30, 35, 89, 116 KDa (CagA), FldA. The DNAs were extracted serially from the biopsy of MALToma patients before and after therapy to perform polymerase chain reaction (PCR) for the immunoglobulin heavy‐chain gene monoclonality. Results. MALToma patients had higher prevalence rates of anti‐FldA protein, 19.5 and 30 KDa antibodies of H. pylori (p < 0.01). After H. pylori eradication, MALToma patients had negative seroconversion of 19.5, 26.5, 30, and 35 KDa antibodies (p < 0.05), but not in CagA and FldA. The PCR monoclonality occurred in 80% (12/15) of the MALToma patients before therapy, but did not correlate with any seroconversion of anti‐H. pylori immunoblots after therapy (p > 0.05). Complete regression of MALToma was observed in 73.3% (11/15) of patients. Evaluation with 20 MHz EUS, for the initial tumor depth and its normalization on the 6th month had 90.9% sensitivity and 100% specificity to predict the complete regression. Discussion. The negative seroconversions of the smaller‐molecular‐weight proteins, but not CagA and FldA, correlate with regression of MALToma by H. pylori eradication. 20 MHz EUS can effectively predict the therapeutic response of MALToma.     

The chaperone Lhs1 contributes to the virulence of the fish-pathogenic oomycete Aphanomyces invadans

Oomycetes are fungal-like eukaryotes and many of them are pathogens that threaten natural ecosystems and cause huge financial losses for the aqua- and agriculture industry. Amongst them, Aphanomyces invadans causes Epizootic Ulcerative Syndrome (EUS) in fish which can be responsible for up to 100% mortality in aquaculture. As other eukaryotic pathogens, in order to establish and promote an infection, A. invadans secretes proteins, which are predicted to overcome host defence mechanisms and interfere with other processes inside the host. We investigated the role of Lhs1 which is part of an ER-resident complex that generally promotes the translocation of proteins from the cytoplasm into the ER for further processing and secretion. Interestingly, proteomic studies reveal that only a subset of virulence factors are affected by the silencing of AiLhs1 in A. invadans indicating various secretion pathways for different proteins. Importantly, changes in the secretome upon silencing of AiLhs1 significantly reduces the virulence of A. invadans in the infection model Galleriamellonella. Furthermore, we show that AiLhs1 is important for the production of zoospores and their cluster formation. This renders proteins required for protein ER translocation as interesting targets for the potential development of alternative disease control strategies in agri- and aquaculture.     

Lymphangioma of the pancreas: a multimodal approach to pre‐operative diagnosis

Background: Lymphangioma of the pancreas is an extremely rare benign tumour of lymphatic origin, with only four cases diagnosed by EUS‐FNA reported to date. Methods and materials: Five cases of either cytologically or histologically diagnosed pancreatic lymphangioma with pre‐operative cytological analysis by EUS‐FNAC were reviewed. Results: All patients were female, with a mean age of 56.4 years. By imaging, the cystic lesions ranged in size from 2 to 7 cm (mean 4.5 cm) and were mainly located in the head of the pancreas. All cysts had thin walls and no cyst demonstrated a mural nodule. Diagnosis based on imaging features was benign in all cases due to the absence of high‐risk features. Four samples were sent for biochemical analysis, which showed low CEA levels (range, <0.5–19.4 ng/ml; mean, 5.45 ng/ml) and CA 19.9 and CA 72.4 levels within normal range. All cyst fluids showed numerous small lymphocytes with no atypia; no epithelial cells were present, including no gastrointestinal contamination. Flow cytometry in two cases showed T lymphocytes with a mature phenotype. Surgical resection in two patients confirmed the cytological diagnosis. Benign clinical follow‐up was available in three patients at 2, 3 and 3.5 years. Conclusion: A multimodal approach to cytological diagnosis (combining clinical, radiological and cyst fluid gross, biochemical and cytological characteristics) can lead to the diagnosis of this cystic neoplasm and distinguish it from other more common cysts in the pancreas, potentially avoiding the need for unnecessary surgery.     

Pancreatobiliary cytology in the multidisciplinary setting

This review article discusses the role of endoscopic ultrasound‐guided fine needle aspiration (EUS FNA) cytology in the clinical management of patients with pancreatic tumours in the setting of a multidisciplinary team (MDT). The commonest diagnosis encountered is pancreatic adenocarcinoma, which is seldom diagnosed early enough for surgical resection. Thus, cytology is likely to be the only form of diagnosis in the majority of cases. Nevertheless, about half the lesions discussed at the MDT meeting are lesions other than primary adenocarcinoma and a wide differential diagnosis must be considered in order to identify tumours, including neuroendocrine tumours, that are amenable to surgical resection. Cytology is not always definitive and the diagnosis may be helped by categorizing results according to whether they are malignant, suspicious, atypical/indeterminate, benign or inadequate. Discussion at MDT meetings and correlation with clinical and imaging findings along with review of cytology slides may allow equivocal results to be clarified before treatment is decided. Inadequate cytology results are avoided by rapid on‐site evaluation of slides; although this is cost‐effective in terms of overall patient care, attendance of cytopathologists on‐site may not be feasible. At Imperial College NHS Trust, specially trained biomedical scientists successfully carry out rapid on‐site evaluation.     

Deep-seated rectal/anal basaloid carcinoma: useful immunocytochemistry in rare squamous cell carcinoma variants

Objectives:  To report the cytological aspects of ano-rectal basaloid carcinoma (BC) variant in endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) conventional and liquid-based cytology (LBC), in a series of 10 cases of deep-seated squamous cell carcinomas (SCC), and to discuss the diagnostic difficulties in interpreting the morphology and immunocytochemical findings.
Methods:  Ten cases of EUS-FNA smears and LBC specimens of deep-seated pelvic masses were retrospectively collected from January 2001 to November 2006.
Results:  Ten EUS-FNA specimen cases were SCC, eight corresponding to usual SCC and two to BC-variant. Of these two cases, only one was correctly diagnosed by EUS-FNA specimen, whereas in the second case, the initial cytological diagnosis was poorly differentiated adenocarcinoma and the final diagnosis of basaloid carcinoma variant was established on surgical resection. Immunocytochemistry (ICC) using CK7, CK20 and CK34βe12 on FNA specimens confirmed the diagnosis retrospectively.
Conclusion:  The diagnosis of basaloid variant of SCC in a rectal location can be very difficult, both on account of the uncommon location and because of the low specificity of morphological aspects on EUS-FNA smears. The immunocytochemical technique, including a limited spectrum of keratins (CK7, CK20, CK34βe12, and p63) is necessary to avoid this diagnostic pitfall.