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

Endoscopic ultrasound-guided fine-needle aspiration vs fine-needle biopsy for the diagnosis of pancreatic neuroendocrine tumors

Background and study aims  Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) as a method of obtaining preoperative diagnosis of pancreatic neuroendocrine tumors (PanNETs) has been reported in several series. Fine-needle biopsies (FNB) are increasingly employed to obtain core specimens during EUS. However, the differences in efficacy between these sampling methods in the diagnosis of PanNETs still needs to be defined. Patients and methods  Over a 13-year period, all patients who underwent EUS-guided tissue sampling of suspicious pancreatic lesions with clinical, endoscopic and pathologic details were entered into an electronic database. Lesions underwent EUS-FNA or FNB sampling, or a combination of the two. The accuracy and safety of different EUS-guided sampling methods for confirmed PanNETs were investigated. Results  A total of 91 patients (M/F: 42/49, median age: 57 years), who underwent 102 EUS procedures had a final diagnosis of PanNET. Both EUS-guided sampling modalities were used in 28 procedures, EUS-FNA alone was used in 61 cases, while EUS-FNB alone in 13 cases. Diagnostic yield of EUS-FNA and EUS-FNB alone, including the inadequate specimens, was 77.5 % (95 %CI: 68.9 - 86.2 %) and 85.4 % (95 %CI: 74.6 - 96.2 %), respectively. The combination of both sampling modalities established the diagnosis in 96.4 % of cases (27/28) (95 %CI: 89.6 - 100 %), significantly superior to EUS-FNA alone ( P  = 0.023). Diagnostic sensitivity among the adequate samples for EUS-FNA, EUS-FNB and for the combination of the two methods was 88.4 % (95 %CI: 80.9 - 96.0 %), 94.3 % (95 %CI: 86.6 - 100 %) and 100 % (95 %CI: 100 - 100 %). There was one reported complication, a post-FNA bleeding, treated conservatively. Conclusions  EUS-FNB improves diagnostic sensitivity and confers additional information to cytological assessment of PanNETs.

Endoscopic ultrasonography and small-bowel endoscopy: Present and future

Over the last decade, impressive technological advances have occurred in ultrasonography and small-bowel endoscopy. Nowadays, endoscopic ultrasonography is an essential diagnostic tool and a therapeutic weapon for pancreatobiliary disorders. Capsule endoscopy and device-assisted enteroscopy have quickly become the reference standard for the diagnosis of small-bowel luminal diseases, thereby leading to radical changes in diagnostic and therapeutic pathways. We herein provide an up-to-date overview of the latest advances in endoscopic ultrasonography and small-bowel endoscopy, focusing on the emerging paradigms and technological innovations that might improve clinical practice in the near future.

An update on the management of pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (PNETs) are a rare and heterogeneous group of neoplasia and differ in their clinical presentation, behavior, and prognosis based on both histological features and cancer stage at the time of diagnosis. Although small-sized tumors can be surgically resected, locally advanced and metastatic tumors confer a poor prognosis. In addition, only limited treatment options are available to the latter group of patients with PNETs, such as hormonal analogs, cytotoxic agents, and targeted therapy. In selected patients, liver-directed therapies are also used. As expected, clinicians taking care of these patients are challenged to develop an effective and comprehensive treatment strategy for their patients amid a wide variety of treatment modalities. Targeted therapy for PNETs is limited to sunitinib and everolimus. Presently, a number of clinical studies are ongoing to assess the efficacy of newer targeted agents alone and in combination with previous agents for the treatment of advanced PNETs. The authors reviewed the current treatment and also discussed the emerging agents and emphasized the need to identify biomarkers.

Two unusual variants of pancreatic neuroendocrine tumor and their potential pitfalls on fine-needle aspiration cytology

Endoscopic ultrasound-guided fine-needle aspiration is increasingly utilized for the diagnosis of pancreatic lesions. Although operator dependent, the procedure has good overall performance characteristics and is minimally invasive; however, accuracy and sensitivity are reportedly lower for pancreatic neuroendocrine tumor (PanNET) compared with the more common pancreatic ductal adenocarcinoma (pACA). The underperformance is further exacerbated by the unusual cases of PanNET presenting with variant cytomorphology. We report two separate diagnostically challenging cases: a pigmented PanNET and a clear cell PanNET. We briefly review the literature and emphasize the importance of recognizing these uncommon variants when encountered in aspirate material. Diagn. Cytopathol. 2017;45:371-378. © 2016 Wiley Periodicals, Inc.

Reliability of Ki-67 Determination in FNA Samples for Grading Pancreatic Neuroendocrine Tumors

Neuroendocrine pancreatic tumors (PanNETs) are graded on the basis of their proliferative activity. Cytological samples are commonly the only samples available, but the determination of Ki-67 in cytology and its reliability as a measure of tumor mitotic activity is not well settled. We have retrospectively reviewed all the cases of FNA under EUS control of PanNETs in a 10-year period (2006-2016) in the Hospital Clínico San Carlos (Madrid). We identified 10 PanNET cases with histological correlation. Median age was 49.4 years and the patients were mainly women. PanNETs were located more frequently in the tail of the pancreas, with a median size of 33.8 mm. None of our cases was a grade 3 tumor. The seven grade 1 tumors confirmed in histology had consistent Ki-67 in cytology. In three cases (30 %), there were discrepancies between the Ki-67 index measured in cytology and histology, and the differences ranged from 2 to 15 %; all these cases were grade 2 tumors in histology and were graded as grade 1 tumors in FNA material. Our results are consistent with previous studies which showed understaging when tumor grade was assessed in cytological samples, mainly in G2 tumors. Previous literature has shown that Ki-67 assessment in EUS-FNA samples is a useful tool to rule out G3 tumors, but can be problematic for distinguishing G1 and G2 tumors.

Clear cell neuroendocrine tumor of pancreas: Endoscopic Ultrasound-guided fine needle aspiration diagnosis of an uncommon variant

The cytomorphologic features of clear cell neuroendocrine tumor of pancreas have been rarely reported in cytology literature. The cytomorphology of this rare variant mimics many primary and metastatic clear cell tumors of the pancreas. However, a precise cytological diagnosis can be rendered by awareness of this entity and judicious use of immunohistochemistry. We report one such case in a young woman diagnosed on endoscopic ultrasound fine needle aspiration. The tumor cells showed positive staining with synaptophysin, chromogranin, and also with inhibin.

Fine-Needle Aspiration Cytology in the Diagnosis of Pancreatic Neuroendocrine Tumors: A Single-Center Experience of 25 Cases

OBJECTIVE

Pancreatic neuroendocrine tumors (Pan NETs) are rare but are being increasingly diagnosed. The objective of this retrospective study was to share our experience of fine-needle aspiration (FNA), including endoscopic ultrasound-guided FNA with rapid on-site evaluation (ROSE), with the use of immunohistochemical (IHC) markers in the diagnosis of Pan NET.

STUDY DESIGN

A total of 25 cases of Pan NET diagnosed on pancreatic FNA between 2008 and 2013 were identified from our hospital database. Clinical history, radiology, cytomorphological features, and IHC performed were reviewed.

RESULTS

The mean age of our patient group was 52 years; 15/25 were male. Most presented with abdominal pain and the majority of the lesions were in the pancreatic body, the largest being 14 cm in size. Based on the 2010 World Health Organization criteria, cases were further graded as follows: 21 cases were grade 1, 2 cases were grade 2 and 2 cases were grade 3. Proliferation marker Ki-67 was utilized in 6 cases for definitive grading. Of the 25 cases, 23 were diagnosed as nonfunctional while 2 were functional; 1 patient had MEN-1 syndrome and 1 had von Recklinghausen's syndrome.

CONCLUSIONS

Our data suggests that FNA, with ROSE and IHC markers, is highly sensitive and specific for diagnosing Pan NET.

Endoscopic diagnosis and treatment of pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (PNETs) are rare pancreatic neoplasms comprising only 1% to 2% of all pancreatic tumors. In recent years, the number of incidentally discovered PNETs has greatly increased given the widespread use of axial imaging. However, a significant proportion of PNETs may not be visualized on conventional imaging such as computed tomography, magnetic resonance imaging, and somatostatin receptor scintigraphy. Endoscopic ultrasound (EUS) has become an integral part of the diagnosis of PNETs because of its high sensitivity for detecting, localizing, and diagnosing PNETs. EUS-guided tissue acquisition provides histologic and immunologic confirmation, and may also allow prognostication about tumor behavior. In addition to preoperative assessment of these tumors, EUS has also been shown to have an important role in nonoperative management of small nonfunctional PNETs. Finally, recent developments suggest that interventional EUS may be used to aid intraoperative localization of PNETs and to deliver therapeutic agents for the treatment of PNETs. This review will discuss the endoscopic diagnosis and treatment of PNETs, with focus on recent advances in the utility of EUS in the clinical management of these tumors.

The usefulness of endoscopic ultrasound-guided fine-needle aspiration for the diagnosis of pancreatic neuroendocrine tumors based on the World Health Organization classification

BACKGROUND

We assessed the controversial topic of using 22-gauge needles in endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) for the diagnosis and evaluation of Ki67 labeling indices (Ki67LI) of pancreatic neuroendocrine tumors (pNET).

METHODS

Thirty-eight patients with pNET who underwent EUS-FNA between January 1, 2008 and December 31, 2012 were enrolled in this study. When available, the Ki67LI and WHO classifications obtained by EUS-FNA and surgical resection were compared.

RESULTS

EUS-FNA with a 22-gauge needle acquired sufficient histological sample to correctly diagnose pNET in 35 cases (92.1%). Both EUS-FNA and surgical histological specimens were available for 19 cases, and grading classes of the 2 procedures were consistent in 17 cases (89.5%) according to the WHO classification based on the Ki67LI. Tumor size was associated with a difference in the Ki67LI between the 2 procedures, although the Ki67LI was almost completely consistent for tumors less than 18 mm in size.

CONCLUSIONS

EUS-FNA with a 22-gauge needle is a safe and highly accurate technique for the diagnosis of pNET. There was a clear correlation between the Ki67LI of histological specimens acquired by EUS-FNA and surgery. EUS-FNA with a 22-gauge needle is useful to predict the WHO classification of pNET.

How can an endosonographer assess for diagnostic sufficiency and options for handling the endoscopic ultrasound-guided fine-needle aspiration specimen and ancillary studies

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has become well established as a minimally invasive technique in diagnosing and staging various gastrointestinal, pancreaticobiliary, and retroperitoneal malignancies. The diagnostic accuracy of this procedure is significantly enhanced by the presence of on-site cytopathology. However, in many EUS centers, cytopathology is not readily available for on-site evaluation. This article is intended to assist the independent endosonographer in the assessment of diagnostic sufficiency and in specimen handling.

Intraductal tubulopapillary neoplasm with expansile invasive carcinoma of the pancreas diagnosed by endoscopic ultrasonography-guided fine needle aspiration: a case report

Intraductal tubulopapillary neoplasm (ITPN) of the pancreas, a novel entity included in the World Health Organization 2010 classification, accounts for <1% of all pancreatic exocrine neoplasms and the number of reported cases is limited in the English literature. Herein we describe the cytologic features of ITPN with invasive carcinoma showing expansile growth on endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) cytology. A 74-year-old male patient is presented with a 6.2 cm irregular mass in the head of the pancreas. Microscopic examination of EUS-FNA material showed abundant branching clusters of cells, with some scattered discohesive cells. High power magnification revealed tubular and cribriform patterns with central lumina, containing mucinous or proteinaceous secretions. The constituent cells were relatively uniform and showed mild to intermediate nuclear atypia. Intracytoplasmic mucin was not identified. On cell-block preparation, luminal spaces of clusters contained wispy luminal mucin. Immunohistochemically, constituent cells were positive for MUC1 and MUC6, and were negative for MUC5AC. The large cribriform and tubular clusters with luminal spaces containing wispy mucin were considered to be diagnostic clues for the cytologic diagnosis of ITPN by EUS-FNA. MUC1, MUC6, and MUC5AC immunohistochemistry for cell-block preparation appears to be a useful adjunctive tool to confirm the diagnosis. On EUS-FNA, ITPN should be included in the differential diagnosis of a pancreatic mass lesion showing good circumscription.

Diagnostic error assessment and associated harm of endoscopic ultrasound-guided fine-needle aspiration of neuroendocrine neoplasms of the pancreas

BACKGROUND

Over the past decade, the standardization of error classification in anatomic pathology has become an important issue. The objective of the current study was to assess the extent of errors occurring in the cytopathologic diagnosis of neuroendocrine lesions of the pancreas, and to classify these errors and their associated harm.

METHODS

Information on all cases diagnosed as a neuroendocrine neoplasm either by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in cytology or by surgical pathology between 2000 and 2012 was collected. Using standardized error and harm classification, the authors reviewed the cytology and surgical pathology material and evaluated the type and the cause of diagnostic errors and their impact on the patient.

RESULTS

A total of 177 patients who underwent EUS-FNA were diagnosed with a neuroendocrine neoplasm either by cytology or surgical pathology. Eighty of these cases had surgical follow-up available at the study institution. Of these 80 cases, 56 had an adequate cell block and immunohistochemistry was performed. There were 14 discrepancies noted between cytologic and surgical pathologic diagnoses. There were 9 false-negative cases, consisting of 3 interpretation errors and 6 cytology sampling errors. There were 5 misclassifications, including 4 cases of solid pseudopapillary neoplasm and 1 case of neuroendocrine carcinoma (diagnosed as adenocarcinoma on cytology). There were no surgical pathology errors noted. All errors were associated with no or minor harm.

CONCLUSIONS

EUS-FNA of pancreatic neuroendocrine neoplasms has excellent diagnostic performance, with no false-positive diagnoses reported. When an adequate sample is obtained, the most significant error is misclassification, which is most often associated with solid pseudopapillary neoplasm. The harm associated with diagnostic errors is at most minor.

Cytologic features of lipid-rich variant of pancreatic endocrine tumor-report of two cases with literature review

Pancreatic endocrine tumor (PET) is an uncommon neoplasm of the pancreas with distinct cytomorphologic features. Lipid-rich PET, a rare variant, histologically deviates from that of a conventional PET. There is only one case report of the cytologic features of this rare entity in the literature. We report two cases of lipid-rich PETs diagnosed by endoscopic ultrasound-guided FNA biopsy. Case 1 showed large aggregates, small clusters, and single cells with plasmacytoid appearance, small uniform nuclei, coarse chromatin, and prominent nucleoli. Abundant distinct small cytoplasmic vacuoles were present in almost all tumor cells and the background was clean. Case 2 showed flat cohesive sheets of medium-sized uniform cells with indistinct plasmacytoid appearance, uniform nuclei, fine and evenly distributed chromatin, and inconspicuous nucleoli. Distinct small cytoplasmic vacuoles were seen only focally. Immunohistochemical stains in cell blocks of both cases confirmed the diagnosis of PET. Lipid-rich PET may be misinterpreted on cytology specimens if the pathologist is not aware of this rare entity since it mimics clear cell carcinoma of the kidney, adrenal cortical neoplasm, or adenocarcinoma of the pancreas.

Endoscopic ultrasonography for pancreatic cancer: current and future perspectives

A suspected pancreatic lesion can be a difficult challenge for the clinician. In the last years we have witnessed tumultuous technological improvements of the radiological and nuclear medicine imaging. Taking this into account, we will try to delineate the new role of endoscopic ultrasound (EUS) in pancreatic imaging and to place it in a shareable diagnostic and staging algorithm of pancreatic cancer (PC). To date the most accurate imaging techniques for the PC remain contrast-enhanced computed tomography (CT) and EUS. The latter has the highest accuracy in detecting small lesions, in assessing tumor size and lymph nodes involvement, but helical CT or an up-to-date magnetic resonance imaging (MRI) must be the first choice in patients with a suspected pancreatic lesion. After this first step there is place for EUS as a second diagnostic level in several cases: negative results on CT/MRI scans and persistent strong clinical suspicion of PC, doubtful results on CT/MRI scans or need for cyto-histological confirmation. In the near future there will be great opportunities for the development of diagnostic and therapeutic EUS and pancreatic pathology could be the best testing bench.

Endoscopic ultrasound in gastroenteropancreatic neuroendocrine tumors

Endoscopic ultrasound (EUS) is an advanced endoscopic technique currently used in the staging and diagnosis of many gastrointestinal neoplasms. The proximity of the echoendoscope to the gastrointestinal tract lends itself to a detailed view of the luminal pathology and the pancreas. This unique ability enables endoscopists to use EUS in patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs). Diagnostic EUS allows previously unidentified NETs to be localized. EUS also determines tumor management by staging the GEP-NETS, enabling the clinicians to choose the appropriate endoscopic or surgical management. The ability to obtain a tissue diagnosis with EUS guidance enables disease confirmation. Finally, recent developments suggest that EUS may be used to deliver therapeutic agents for the treatment of NETs. This review will highlight the advances in our knowledge of EUS in the clinical management of these tumors.

Analysis of lymph node metastasis in pancreatic neuroendocrine tumors (PNETs) based on the tumor size and hormonal production

BACKGROUND

Because of the rarity and variety of pancreatic neuroendocrine tumors (PNETs), there have been few reports regarding the indication for lymph node dissection in patients with these tumors. This study aimed to evaluate the risk of lymph node metastasis of PNETs based on the tumor size and hormonal production.

METHODS

Data for a total of 66 patients who had PNETs resected at our department between 1987 and 2010 were retrospectively studied. The clinicopathological features, including the disease-specific survival rate, were assessed based on the status of lymph node metastasis at the time of initial surgical resection. Then the cut-off point of tumor size to predict lymph node metastasis was estimated.

RESULTS

There were 12 patients (18%) with lymph node metastasis. The frequency of lymph node metastasis tended to be higher in gastrinomas than that in other tumors (43 vs. 15%; P = 0.08). The size of PNETs with lymph node metastasis was significantly larger than that of the PNETs without metastasis (P = 0.04). The postoperative survival rate in the PNET patients with lymph node metastasis was significantly lower than that in the patients without metastasis (P < 0.0001). Only 2 (8%) of 26 PNETs with a tumor size of <15 mm had lymph node metastasis, and both of these were gastrinomas. On the other hand, 10 (25%) of the remaining 40 PNETs with a tumor size of ≥15 mm had lymph node metastasis. Notably, there were no PNETs with lymph node metastasis in 22 non-gastrinomas with a tumor size of <15 mm.

CONCLUSIONS

Non-gastrinomas with a tumor size of ≥15 mm and all gastrinomas would be an indication for pancreatectomy with lymph node dissection.

EUS for pancreatic neuroendocrine tumors: a single-center, 11-year experience

BACKGROUND

Pancreatic neuroendocrine tumors (PNTs) are rare tumors with malignant potential. EUS and EUS-guided FNA (EUS-FNA) have been shown to be superior to other imaging methods in the preoperative localization and diagnosis of PNTs.

OBJECTIVES

To evaluate the clinical presentation, EUS morphology, and sensitivity of EUS-FNA cytology in a large consecutive cohort with histologically and/or cytologically confirmed PNTs.

DESIGN

Retrospective study of all consecutive patients from July 1995 to November 2006 who underwent EUS for a known or suspected PNT and had a subsequently histologically confirmed PNT.

SETTING

Tertiary referral center.

PATIENTS

Ninety-two patients with suspected PNT.

INTERVENTIONS

EUS evaluation with or without EUS-FNA of PNTs.

MAIN OUTCOME MEASUREMENTS

Clinical and EUS features of PNTs and sensitivity of EUS-FNA for the diagnosis of PNTs.

RESULTS

Ninety-two patients underwent EUS; 76 patients had confirmed histopathology, of whom 69 (91%) were symptomatic. Patients with functional PNTs presented with diarrhea, peptic ulcer disease, and hypoglycemia. Tumor locations and echogenic features were similar except that nonfunctional PNTs tended to be larger and have cystic features. Patients with malignant PNTs were older (P = .03), presented with abdominal pain, and had larger tumors (P = .0006) with irregular margins. Eighty-nine percent of patients underwent EUS-FNA. Sensitivity of EUS-FNA for the diagnosis of a PNT was 87%. Sensitivity of EUS-FNA was similar in functional and nonfunctional PNTs. The sensitivity of EUS-FNA was higher for malignant PNTs (P = .008).

LIMITATIONS

Retrospective single tertiary center.

CONCLUSIONS

EUS and EUS-FNA are sensitive tools, especially in cases of suspected symptomatic PNTs in which other imaging modalities have failed.

Preliminary experience with a new cytology brush in EUS-guided FNA

BACKGROUND

Despite the high diagnostic yield of EUS-guided FNA, room for technical improvements remains. Recently, the EchoBrush (Cook Endoscopy, Winston-Salem, NC), a disposable cytologic brush, was introduced to the market. To date, only 1 study, limited to 10 pancreatic cyst cases, using this device has been published.

OBJECTIVE

To assess the diagnostic yield of the EchoBrush in a cohort of consecutive patients, irrespective of the target lesion.

DESIGN

Case series.

SETTING

Tertiary care university hospital (Molinette Hospital, Turin, Italy).

PATIENTS

Thirty-nine consecutive patients (12 with solid pancreatic masses, 12 with pancreatic cysts, 7 with enlarged lymph nodes, and 8 with submucosal masses) were enrolled.

INTERVENTIONS

The material collected with the EchoBrush and with a standard FNA needle was double-blind evaluated by 2 cytopathologists.

MAIN OUTCOME MEASUREMENTS

Adequacy of the sample and sensitivity and specificity of the EchoBrush method.

RESULTS

Adequate material for cytologic analysis was collected in 17 of 39 patients (43.6%) with a single pass of the EchoBrush. Results were better for pancreatic lesions (for solid and cystic lesions, the adequacy was 58.3% and 50%, respectively); adequacy was low (28.6% and 25%, respectively) for lymph nodes and submucosal masses. The overall sensitivity and specificity were 57.9% and 31.2%, respectively. There were no adverse events with the procedure.

LIMITATION

Preliminary study.

CONCLUSIONS

This report suggests that the EchoBrush may provide adequate cellularity to diagnose solid and cystic pancreatic lesions. More extensive studies are needed to compare the EchoBrush and standard needles.

Pancreatic endocrine tumors: a large single-center experience

OBJECTIVES

Pancreatic endocrine tumors (PETs) are infrequent, which makes large experiences unlikely. Our aim was to describe a large single-center experience with PETs and the use of endoscopic ultrasound (EUS) and a cancer staging system (TNM).

METHODS

This study involves a retrospective analysis of 86 patients (44 men; age, 58 +/- 14 years) who underwent EUS-fine needle aspiration (EUS-FNA). Immunohistochemistry was used. Lesions were classified as recommended by TNM classification.

RESULTS

Typical EUS features were well-demarcated, hypoechoic, solid, homogeneous lesions. Ninety percent had the diagnosis obtained by EUS-FNA. Twelve PETs (14%) were functioning, 8 (9.3%) were cystic, and 14 (16%) were 10 mm or smaller. Nonfunctional PETs and larger lesions were more advanced. The TNM stage was I in 24, II in 10, III in 18, and IV in 34 patients. Sixteen patients (27%) died, and 30 patients (52%) had progression/recurrence during the follow-up (34 +/- 27 months). TNM stage and surgery with curative intent were related to progression. The overall 5-year survival was 60%. The mean survival time was 94 +/- 12 months for stage I, 52 +/- 12 months for stage III, and 54 +/- 7 months for stage IV (P = 0.06).

CONCLUSIONS

Nonfunctional PETs were more common and advanced. The EUS-FNA has a high accuracy for diagnosing PETs. Progression and poorer survival were associated with TNM stage.

FNAC diagnosis of pancreatic somatostatinoma

Somatostatinomas are rare pancreatic endocrine neoplasms (PEN). We present a case of a PEN in a 63-year-old lady having diabetes mellitus, cholelithiasis, steatorrhea, weight loss, indigestion, nausea and fatigue. Ultrasonography revealed a large calcified mass occupying the liver, pancreas and emboli in the splenic vein. Fine needle aspiration cytology (FNAC) of the metastatic mass in the liver showed features of neuroendocrine tumor. Correlating the clinical picture, computed tomography and cytological findings, a diagnosis of pancreatic somatostatinoma was suggested. Serum somatostatin levels and biopsy findings confirmed the same. The patient was put on chemotherapeutic agents and octreotide and is doing well after two years of follow-up. We discuss the FNAC findings of pancreatic endocrine tumors and its differentiating features from hepatoma and other small round cell tumors.

The role of cytomorphology and proliferative activity in predicting biologic behavior of pancreatic neuroendocrine tumors: a study by endoscopic ultrasound-guided fine-needle aspiration cytology

BACKGROUND

The biologic behavior of pancreatic neuroendocrine tumors (NETs) is difficult to predict in the absence of metastases or invasion into adjacent organs. In this study, the authors retrospectively evaluated the cytopathology and proliferative activity in cytology specimens obtained by endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA).

METHODS

Thirty-five patients who were diagnosed with pancreatic NET based on EUS-guided FNA were studied retrospectively (2002-2007). Cytopathology and proliferative activity (Ki-67) in cytology specimens were reviewed. Patients were divided into 2 groups: Group A (all patients with simultaneous, suspicious, metastatic masses [unresectable tumors]) and Group B (patients with final histopathologic diagnosis). Moreover, the patients in Group B were classified into 4 risk subgroups according to the 2004 World Health Organization (WHO) classification (Subgroups 1a, 1b, 2, and 3).

RESULTS

Thirteen of 35 patients who were diagnosed with unequivocally malignant tumors were placed in Group A (unresectable tumors), and 22 of 35 patients were placed in Group B. In Group A, >2% Ki-67-positive cells were present in 12 of 13 patients (92.3%). In Group B, >2% Ki-67-positive cells were present in 0 of 6 patients in WHO Subgroup 1a (0%), in 3 of 7 patients in WHO Subgroup 1b (42.86%), in 7 of 7 patients in WHO Subgroup 2 (100%), and in 2 of 2 patients in WHO Subgroup 3 (100%). In Group A, nuclear pleomorphism/multinucleation was observed in 8 or 13 patients (61.53%). In Group B, nuclear pleomorphism/multinucleation was observed in 4 of 7 patients in WHO Subgroup 2 (57.14%) and in 2 of 2 patients in WHO Subgroup 3 (100%). In Group A, nucleoli were present in 7 of 13 patients (53.85%); whereas, in Group B, nucleoli were present in 6 of 7 patients in WHO Subgroup 2 (85.7%) and in 2 of 2 patients in WHO Subgroup 3 (100%). None of the remaining cytologic features that were evaluated (necrosis, mitoses, spindle cells, and molding/crush artifact) were observed consistently in malignant NETs.

CONCLUSIONS

The current results indicated that Ki-67 evaluation in routine EUS-FNA cytology specimens can be used as a potential prognostic marker in pancreatic NETs. Nuclear pleomorphism/multinucleation and the presence of nucleoli also are reliable for predicting malignant pancreatic NETs. Cancer (Cancer Cytopathol) 2009. (c) 2009 American Cancer Society.

Cystic pancreatic endocrine tumors: an endoscopic ultrasound-guided fine-needle aspiration biopsy study with histologic correlation

BACKGROUND

Cystic pancreatic endocrine tumors (PETs) are rare neoplasms with a preoperative diagnostic challenge. The aim of this study was to evaluate the preoperative diagnostic strategy for these tumors and to assess the clinical and pathologic characteristics.

METHODS

Six cases of cystic PET were retrospectively enrolled. Endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) was performed in 4 cases. All cytomorphologic data from conventional smears, ThinPrep preparations, and cell block preparations were reported in detail.

RESULTS

There were 3 male and 3 female patients with a mean age of 52.3 years. Tumor size ranged from 10 mm to 60 mm (mean, 29.8 mm). EUS-FNAB contributed to an accurate diagnosis in all cases. Cytologically, loosely cohesive aggregates and single cells were predominant. Cells were small and typically plasmacytoid, with occasional cytoplasmic vacuolization. Nuclei were round or oval, uniform, with finely and evenly distributed chromatin. Immunocytochemistry confirmed the endocrine differentiation. Histologic findings were typical for endocrine proliferation. All tumors were well differentiated.

CONCLUSIONS

Cystic PET is an unusual finding that presents diagnostic challenges for both endoscopists and cytologists. EUS-FNAB with the Thinprep preparation technique and cell block material were found to be helpful in improving diagnostic accuracy. Immunocytochemical staining with endocrine markers confirmed the diagnosis.

Proliferative rate in endoscopic ultrasound fine-needle aspiration of pancreatic endocrine tumors: correlation with clinical behavior

BACKGROUND

The objectives of this study were to evaluate the role of endoscopic ultrasonography (EUS)-guided fine-needle aspiration (FNA) in the preoperative diagnosis of pancreatic endocrine tumors (PETs) and to investigate whether the Ki-67 index determined on cytologic material could help predict their behavior.

METHODS

The study included 10 men and 5 women (ratio of men to women, 2:1) with a mean age of 62.4 years (range, 40-79 years). Diff-Quik- and Papanicolaou-stained FNA samples were analyzed retrospectively, and immunocytochemical stains were performed for chromogranin A, synaptophysin, vimentin, alpha-1-antitrypsin, and Ki-67 on cell block sections. The Ki-67 index was evaluated by using digital image-analysis software and was correlated with follow-up (mean, 21.5 months; range, 2-43 months).

RESULTS

The overall survival was rate 86.7% (13 of 15 patients). Seven of 15 patients (46.7%) patients developed lymph node and/or hematogenous metastases. The Ki-67 index in PETs with no metastases was lower (mean, 6.3%; range, 2%-13%) than in clinically aggressive (metastatic) tumors (mean, 7.7%; range, 3%-27%; P = .03). None of the tumors that had a Ki-67 index < or =2% were metastatic. Both patients who died of disease had a Ki-67 index of 4%.

CONCLUSIONS

Although tumors with metastatic potential tended to exhibit a slightly higher Ki-67 index, there was a significant overlap with nonmetastatic tumors, and PETs that had a very low proliferative rate still could behave aggressively; therefore, the authors concluded that the Ki-67 index does not predict the risk of disease progression in patients with PETs.

Endoscopic ultrasound-guided fine-needle aspiration cytology of pancreatic neuroendocrine tumors: a study of 48 cases

BACKGROUND

Neuroendocrine tumors (NETs) of the pancreas are relatively uncommon tumors. The objective of this report was to describe the cytopathologic and immunocytochemical features of NETs obtained by endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA).

METHODS

Forty-eight patients who were diagnosed with pancreatic NETs based on EUS-guided FNA were studied retrospectively (from 2002 to 2007). Clinical data, EUS findings, cytopathologic features, and immunocytochemical stains were reviewed for this study. The final histopathologic diagnosis from each patient also was available for comparison.

RESULTS

Forty-eight patients (28 men and 20 women) who ranged in age from 16 years to 86 years were selected and had the following clinical findings: solid or multiple pancreatic masses diagnosed by computed tomography or magnetic resonance imaging studies; simultaneous, suspicious, metastatic masses in the liver, mediastinum, and/or lung; hypoglycemia; multiple endocrine neoplasia type 1 syndrome; von Hippel-Lindau syndrome; and primary NET of the small bowel. EUS findings revealed solid or multiple masses in the pancreatic head/uncinate, or in the pancreatic body/tail, or simultaneously in the pancreatic head/uncinate and body/tail. Cytologically, 40 patients were diagnosed with NETs (histopathogically confirmed), and 8 patients had findings that were suspicious of NETs (2 patients had false-positive results, and 6 patients had histopathologically confirmed NETs). The most helpful cytologic findings for the diagnosis of NET were a richly cellular sample with a monotonous, poorly cohesive population of small or medium-sized cells with granular chromatin (salt and pepper) and plasmacytoid morphology. Immunocytochemistry confirmed the neuroendocrine origin of tumors in 40 patients (material for immunocytochemistry was inadequate in 8 patients).

CONCLUSIONS

The current results indicated that EUS-guided FNA is a useful method for the diagnosis of pancreatic NETs. Cytopathologic examination in coordination with immunocytochemistry can provide an accurate diagnosis in most patients.

Neuroendocrine tumors of the pancreas: endoscopic diagnosis

PURPOSE OF REVIEW

Endoscopic ultrasound (EUS) is a valuable tool in the diagnosis and management of pancreatic neuroendocrine tumors. This review highlights advances over the last year in EUS in the evaluation of pancreatic neuroendocrine tumors.

RECENT FINDINGS

We will focus on recent findings regarding the accuracy of EUS, EUS-guided fine needle aspiration (EUS-fine needle aspiration), emerging cytologic markers obtained from fine needle aspiration samples, and the role of EUS screening for patients with multiple endocrine neoplasia type 1 syndrome. Additionally, we will introduce potential therapeutic EUS interventions in the treatment of pancreatic neuroendocrine tumors.

SUMMARY

The present review highlights recent advances in the utility of EUS in the clinical management of pancreatic neuroendocrine tumors. Key studies from the last year demonstrate the important role of EUS in the diagnosis, prognosis, and treatment of pancreatic neuroendocrine tumors.

Sporadically occurring functional pancreatic endocrine tumors: review of recent literature

PURPOSE OF REVIEW

Pancreatic neuroendocrine tumors are rare neoplasms often associated with a clinical syndrome. Their rarity makes a comprehensive study difficult at any single institution, while their uniqueness makes them desirable for investigation. This review summarizes recent information and advancements concerning pancreatic neuroendocrine tumor diagnosis, imaging characteristics, treatment algorithms, and staging.

RECENT FINDINGS

Insulinomas and gastrinomas comprise the majority of functional pancreatic neuroendocrine tumors. Advances in their identification and diagnostic evaluation, imaging techniques, and treatment algorithms are presented. Furthermore, a new staging classification system has been proposed which may significantly improve the ability to conduct future multi-institutional investigations on pancreatic neuroendocrine tumors.

SUMMARY

Although rare, a thorough understanding of pancreatic neuroendocrine tumors is essential for all physicians due to the wide variety of symptoms with which patients present. Currently, patients are often misdiagnosed for extended periods of time. This review summarizes the recently published literature about diagnosis, imaging, treatment, and staging of pancreatic neuroendocrine tumors.

Endoscopic ultrasound-guided fine needle aspiration cytology of the pancreas: a morphological and multimodal approach to the diagnosis of solid and cystic mass lesions

Cytological evaluation of pancreatic masses and cysts is the preferred pre-operative diagnostic modality and is increasingly being performed by endoscopic ultrasound. This review focuses on the multimodal approach at the Massachusetts General Hospital that utilizes clinical, cytological, radiological and ancillary studies in rendering a final cytological diagnosis.

Cytologic diagnosis of pancreatic endocrine tumors by endoscopic ultrasound-guided fine-needle aspiration: A review

Precise localization and diagnosis of pancreatic endocrine tumors (PETs) is important, because pancreatic PETs have different clinical and biological behavior and treatment modalities than do exocrine pancreatic tumors. In contrast to the much more common exocrine adenocarcinomas, cytologic studies of PET are relatively rare and many cytopathologists lack experience with the cytomorphologic features of these tumors.During the last 10 yr, endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) has matured into an accurate, highly sensitive, and cost-effective modality for the preoperative localization of pancreatic PETs. This has resulted in an increased number of PETs first sampled as cytology specimens. This manuscript focuses on the cytomorphologic features most suggestive of pancreatic PETs, differential diagnosis, and diagnostic pitfalls of PETs. The technical development of EUS-guided FNA and the ancillary studies for pancreatic PETs are also reviewed. The data summarized in this review indicate that EUS-FNA is a valuable method in the recognition of pancreatic PETs and in most cases cytopathologists could reach a correct diagnosis of these tumors, including their hormone producing capability on aspirated cytologic material.