Fine needle aspiration cytology of thymic tumors

Cytologic material was reviewed from 23 mediastinal tumors clinically suspected as thymomas. The thymomas had a characteristic biphasic cell pattern in material obtained by fine needle aspiration biopsy that was easy to recognize and possible to differentiate from carcinoid tumors, malignant lymphomas and oat-cell carcinomas.     

Intracranial germ cell tumors: association with Klinefelter syndrome and sex chromosome aneuploidies

Intracranial germ cell tumors (ICGCTs) occur mainly in male children and adolescents. Polyploidy of the X chromosome and X hypomethylation have been suggested as mechanisms of malignant transformation independently of the histological tumor type. On the other hand, several reports associate these tumors with Klinefelter's syndrome (KS). Recent reports indicate that KS patients have an increased relative risk for development of malignant mediastinal germ cell tumors and also around 8% of male patients with primary mediastinal tumors have KS. In an attempt to explore the frequency of KS amongst patients with ICGCTs and to confirm the presence of X chromosome polyploidies in these tumors, we studied 13 young male patients with ICGCTs. Paraffin-embedded tumoral and normal tissues were studied by FISH. KS was found in 15% of the cases, demonstrating that this constitutive aneuploidy may be related to carcinogenesis. When tumor and non-tumor tissues were compared, statistically significant X and Y chromosome polyploidies in tumors were revealed. These results emphasize that aneuploidies are involved in ICGCT tumorigenesis.     

Combination percutaneous cryotherapy and iodine-125 seed implantation for unresectable malignant thymoma: Experience in 19 patients

Thymomas are the most common tumors of the mediastinum. These tumors often compress vital mediastinal organs and severely impact the quality of life of thymoma patients. To avoid the side effects of chemoradiotherapy, some patients with unresectable malignant thymomas have opted to undergo cryotherapy in our hospital. We reviewed the cryosurgery, nursing and follow-up records of our hospital for the past 8 years, and evaluated the safety and efficiency of cryotherapy in 19 patients with unresectable malignant thymomas. No severe complications involving the vital organs surrounding the tumor occurred during or after cryosurgery. The most common side effect was pleural effusion, which occurred in 11 patients and healed after drainage within 1 week. Cough, mediastinal and pericardial effusions, pneumothorax, mild fever and chest tightness also occurred and resolved 1 week after symptomatic treatment. Since our patients had high KPS scores and mild myasthenia gravis symptoms before the treatment, myasthenia gravis did not occur after the treatment. The progression-free survival of the patients was 14–29 months (median, 18 months), and did not differ between patients with large tumors and those with small tumors (P = 0.6753). In conclusion, cryotherapy is a safe and efficient method for the treatment of unresectable malignant thymoma.     

Distinct helper virus requirements for Abelson murine leukemia virus-induced pre-B- and T-cell lymphomas.

Abelson murine leukemia virus (A-MuLV) can induce pre-B- or T-cell lymphomas (thymomas) in mice depending on the route and time of injection. Previous studies have shown that the choice of the helper virus used to rescue A-MuLV greatly influences its ability to induce pre-B-cell lymphomas. In this study, we investigated the role of the helper virus in A-MuLV-induced thymomas. A-MuLV rescued with the helper Moloney MuLV, BALB/c endogenous N-tropic MuLV, and two chimeric MuLVs derived from these two parents were injected intrathymically in young adult NIH Swiss mice. All four A-MuLV pseudotypes were found to be equally efficient in the induction of thymomas, whereas drastic differences were observed in their pre-B-cell lymphomagenic potential. Thymoma induction by A-MuLV was independent of the replication potential of the helper virus in the thymus, and no helper proviral sequences could be detected in the majority of thymomas induced by A-MuLV rescued with parental BALB/c endogenous or chimeric MuLVs. In the thymomas in which helper proviruses were present, none of them were found integrated in the Ahi-1 region, a common proviral integration site found in A-MuLV-induced pre-B-cell lymphomas (Y. Poirer, C. Kozak, and P. Jolicoeur, J. Virol. 62:3985-3992, 1988). In addition, helper-free stocks of A-MuLV were found to be as lymphomagneic as other pseudotypes in inducing thymomas after intrathymic inoculation, in contrast to their inability to induce pre-B-cell lymphomas when injected intraperitoneally in newborn mice. Restriction enzyme analysis revealed one to three A-MuLV proviruses in each thymoma, indicating the oligoclonality of these tumors. Analysis of the immunoglobulin and T-cell receptor loci confirmed that the major population of cells of these primary thymomas belongs to the T-cell lineage. Together, these results indicate that the helper virus has no effect in the induction of A-MuLV-induced T-cell lymphomas, in contrast to its important role in the induction of A-MuLV-induced pre-B-cell lymphomas. Our data also revealed distinct biological requirements for transformation of these two target cells by v-abl.     

Identification of types and primary sites of malignant tumors by examination of exfoliated tumor cells in serous fluids. Comparison with the diagnostic accuracy on small histologic biopsies

The accuracy of identification of tumor type and primary site of malignant tumors by examination of exfoliated tumor cells was cytologically studied in 448 malignant effusions from 366 patients for whom the primary tumor site had been confirmed by histology. Ninety-seven corresponding small biopsies from metastases were separately reviewed histopathologically. In four fluids, the cells were too scanty or too poorly preserved for tumor typing. The cytologic tumor typing was performed with nearly 100% accuracy in the remaining 444 fluids, except for those of intermediate-cell anaplastic carcinomas (0 of 3) and poorly differentiated squamous (epidermoid) carcinomas (1 of 5). Adenocarcinoma was correctly identified in 98% of 285 fluids, large-cell carcinoma in 97% of 108 fluids, oat-cell carcinoma in 94% of 16 fluids, well-differentiated (keratinizing) squamous carcinoma in 100% of 3 fluids, malignant lymphoma in 100% of 22 fluids and sarcoma in 100% of 2 fluids. The criteria and the failures are discussed at length. In the investigation of the accuracy of cytologic and histologic diagnoses with respect to the primary tumor site, tumors with variable sites of origin (sarcomas and lymphomas) and those with usually singular sites of origin (e.g., small-cell anaplastic carcinoma of the lung) were excluded, leaving 387 cytologic and 83 histologic specimens available for review. The breast as a primary site was correctly identified in 70% of both the cytologic and histologic specimens; the primary cytodiagnostic criteria included a uniform cell pattern, finely granular chromatin, dense cytoplasm and cell balls with smooth borders. Ovarian primaries were correctly identified in 70% of the fluids and 83% of the biopsy samples on the basis of very irregular clusters of large pleomorphic tumor cells, large nucleoli and psammoma bodies. Lung primaries, identified in 50% of the fluids and 29% of the biopsy samples, showed quite variable cell patterns, most often including large pleomorphic cells with or without mucus formation and prominent multinucleation. Gastric cancers of the diffuse type were accurately identified in 52% of the corresponding fluids, which showed mainly isolated cells with dense cytoplasmic rims, occasional signet-ring cells, "embryo-shaped" nuclei, marked hyperchromasia and densely granular chromatin.(ABSTRACT TRUNCATED AT 400 WORDS)     

Fine needle aspiration cytology of rare malignant tumors of the breast.

This report describes the fine needle aspiration (FNA) cytologic findings in 17 rare malignant breast tumors. The series consisted of invasive cribriform carcinoma, papillary carcinoma, apocrine carcinoma, carcinoma with pseudosarcomatous metaplasia, carcinosarcoma, fibrosarcoma, malignant phyllodes tumors, primary malignant lymphomas, plasmocytoma, metastatic melanoma and metastatic renal clear cell carcinoma. Besides cytomorphology, the results of immunostaining in eight cases are presented, as is a review of the literature. It is important for rare primary malignancies, as well as for metastatic tumors, to be diagnosed, or at least have the diagnosis suggested, preoperatively by FNA and immunocytochemistry, permitting better therapy planning.     

Cytologic features of malignant peripheral nerve sheath tumor

OBJECTIVE: To study the cytomorphologic features of malignant peripheral nerve sheath tumor (MPNST), including the epithelioid cell variant, and to establish differential diagnostic features with benign neurogenic tumors and other sarcomas. STUDY DESIGN: Cytologic smears from primary, recurrent and metastatic tumors in 10 patients with MPNST were reviewed. Three patients had neurofibromatosis 1 (NF1), and in two others the tumor arose from a preexisting neurofibroma. Immunocytochemical evaluation of S-100 protein was performed in four cases. A complete pathologic study was available in all cases. To assess the validity of morphologic recognition, a blinded study, including eight cases of spindle MPNST among smears from histologically proven schwannomas, synovial sarcomas, leiomyosarcomas, malignant fibrous histiocytomas and liposarcomas, was performed. RESULTS: Neurogenic differentiation was recognizable in four cases (differentiated), while the other four (anaplastic) were indistinguishable from other pleomorphic sarcomas. The presence of elongated, slender, often wavy nuclei and less commonly a delicate, fibrillary metachromatic stroma were features suggestive of nerve sheath differentiation. Other cytologic, as well as clinical, features permitted their identification as malignant. Two cases of epithelioid MPNST disclosed large, polygonal to plasmocytoid tumor cells without specific cytologic features. S-100 immunoexpression was positive in two of the four cytologic samples tested. CONCLUSION: Although no morphologic findings are specific to MPNST, the above-mentioned cytologic features may suggest, in differentiated cases, its neurogenic differentiation. On the basis of morphologic features alone, the diagnosis of anaplastic and epithelioid MPNST is not possible, and immunocytochemical and ultrastructural studies are necessary. A specific cytodiagnosis is possible in recurrences, metastases and cases of NF1 or a preexisting neurofibroma.     

Twist 在胸腺上皮性肿瘤中的表达及预后意义

目的:检测Twist在胸腺上皮性肿瘤的表达及其与预后的关系。方法:应用免疫组织化学pv6000法检测Twist在87例胸腺上皮性肿瘤(胸腺瘤71例,胸腺癌16例)中的表达情况,分析其与患者各项临床病理指标及预后的关系。结果:Twist蛋白在胸腺癌的阳性表达(81.3%)显著高于胸腺瘤组织(11.3%),其阳性表达的差异存在统计学意义(P<0.001),其在胸腺瘤各亚型之间表达的差异无统计学意义(P>0.05)。Twist阳性表达与胸腺上皮性肿瘤术后发生远处转移呈正相关关系(r=0.40,P=0.001)。Kaplan-Meier生存分析显示Twist阳性表达患者术后生存期低于Twist阴性表达患者(P<0.001)。结论:检测Twist蛋白表达情况对于鉴别胸腺瘤与胸腺癌可能有重要的参考价值,Twist阳性表达可能与术后发生远处转移有关并影响患者术后生存期。     

乳腺恶性血液病的病理类型、临床特点及生存分析

目的:探讨乳腺恶性血液病的病理分型、患者的临床特征及预后。方法:回顾性分析2014年1月至2019年1月空军军医大学西京医院收治的33例乳腺恶性血液病患者的病理分型、临床特征及预后。结果:33例患者中,32例为女性,1例为男性,平均年龄为45.5岁(12-78岁)。经病理确诊29例(29/33,87.9%)为非霍奇金淋巴瘤,其中弥漫大B细胞淋巴瘤(18/29,62.1%)最为常见,其次是NK/T细胞淋巴瘤(3/29,10.3%),B淋巴母细胞白血病/淋巴瘤(2/29,6.8%),而伯基特淋巴瘤、滤泡淋巴瘤、原发皮肤间变大细胞淋巴瘤各1例(1/29,3.4%),其余3例未进一步分型。此外,1例(1/33,3.0%)霍奇金淋巴瘤,3例(3/33,9.1%)急性白血病复发累及乳腺。原发性乳腺恶性血液病为19例(57.6%),继发性为14例(42.4%),病变主要累及右侧乳腺(18例,54.5%),其次为左侧(10例,30.3%),双侧均累及的为少数(5例,15.2%)。19例原发性乳腺恶性血液病均为淋巴瘤,与14例继发性乳腺恶性血液病相比,其血小板计数明显升高(P=0.004),β2-MG显著降低(P=0.049),B症状少(P=0.017),Ann Arbor分期主要为Ⅰ-Ⅱ期(P<0.01),骨髓受累少(P<0.01)等特点。生存分析提示原发性乳腺恶性血液病患者比继发性患者生存期更长(HR=9.846,P=0.002)。恶性血液病累及骨髓可导致生存期显著缩短(HR=6.434,P<0.01)。结论:乳腺恶性血液病患者以中年女性为主,原发性乳腺恶性血液病比继发性发病率高(分别为57.5%和42.5%),最常见的病理类型为弥漫大B细胞淋巴瘤,病变主要累及右侧乳腺。与继发性乳腺恶性血液病相比,原发性乳腺恶性血液病患者具有血小板计数相对更高,β2-MG水平更低,往往不伴B症状,Ann Arbor分期主要为Ⅰ-Ⅱ期,骨髓不受累,且生存期显著延长等特点。此外,恶性血液病累及骨髓提示预后不良。     

Epithelial cell type, clinical behaviour and AgNOR counts in thymic epithelial tumours

The relationship between epithelial cell type, clinical behaviour and number of nucleolar organiser regions (AgNORs) was investigated in 37 thymomas and three thymic carcinomas. The thymomas were classified according to epithelial cell morphology as cortical (16 cases), medullary (8 cases) or mixed (13 cases). Seven cortical tumours had infiltrated the capsule or adjacent structures at the time of operation, whereas only one medullary and two mixed tumours showed evidence of invasion, the differences being statistically significant (P less than 0.01). None of the patients with medullary thymoma had myasthenia gravis, but there was a significantly higher incidence (P less than 0.001) among those with cortical or mixed tumours (six and three cases respectively). The mean AgNOR count for medullary tumours was 1.56, compared with 2.22 and 2.06 for cortical and mixed tumours. Although the counts for medullary tumours were significantly lower than for the other two types (P less than 0.01), there was considerable overlap. The mean count for the carcinomas was 4.94--significantly higher than for the thymomas (P less than 0.01)--but again overlap was considerable. No relationship was demonstrable between AgNOR counts, clinical stage, incidence of myasthenia or recurrence. It is concluded that although classification of thymomas based on epithelial cell type represents an improvement on previous classifications, it must be applied with caution. Similarly, AgNOR counts may give some indication of malignant potential, but their usefulness in individual cases is doubtful.     

Malignant melanoma of mediastinum misdiagnosed as a spindle cell thymoma in a fine needle aspirate: a case report

BACKGROUND: Malignant melanomas in the medastinum are extremely rare. Both primary melanomas and metastatic lesions from a primary elsewhere can occur in the mediastinum. Aspiration biopsy of a melanoma at this unusual site may pose problems in diagnosis. CASE: A 35-year-old woman presented with an anterior mediastinal mass. Cytologic smears were hemorrhaghic and revealed a loosely dispersed population of spindle cells with prominent nucleoli. In view of the location, the possibility of spindle cell thymoma was suggested on cytology. Subsequent histology revealed a malignant melanoma. CONCLUSION: This case stresses that the cytopathologist should keep in mind the remote differential diagnosis of a malignant melanoma while evaluating spindle cell neoplasms of the mediastinum, especially in tumors with prominent cell dispersal and with cells that have prominent nucleoli even without melanin pigment. Accurate diagnosis helps in evaluating patients and avoids unnecessary surgery when the lesion represents a metastasis to the mediastinum from a primary elsewhere.     

c-MYC, RB-1, TP53, and centromere 8 and 17 copy number in B-cell non-Hodgkin's lymphomas assessed by dual-color fluorescence in situ hybridization.

Dual-color interphase FISH was performed to B-cell Non-Hodgkin's lymphomas to detect numerical genetic alterations in c-MYC, RB-1, TP53 and centromere 8 and 17. The probe combinations c-MYC/centromere 8, RB-1/centromere 8 and TP53/centromere 17 were applied, and the hybridization signals scored in a correlated fashion. Copy number aberrations was found in 24 of 45 lymphomas examined (53%). Nine tumors (20%) had increased c-MYC gene copy number (three to 8 copies). Seven of these nine had increase in c-MYC copies relative to centromere 8 copy number. Allelic loss of RB-1 was found in 9 tumors (20%), one tumor lacked both alleles. Nine cases (20%) showed hemizygous TP53 deletion. TP53 deletion was significantly associated with high-grade histology (P = 0.02). Numerical alterations in c-MYC and RB-1 were not associated with prognosis. Patients with hemizygous TP53 deletion had shorter survival (relative risk = 6.1, P<0.001) than the ones with two or more alleles.     

Aromatase cytochrome P450 and estrogen and progesterone receptors in uterine sarcomas: correlation with clinical parameters

We examined the immunohistochemical expression of aromatase cytochrome P450 (P450arom), estrogen receptor (ER), progesterone receptor (PR), and Ki-67 in postoperative uterine sarcomas (n = 31) and the corresponding eutopic endometria (n = 20) to evaluate the relationships between the endocrine character of uterine sarcomas and the clinical features. In sarcoma tissues, P450arom was detected in 55% of cases, ER in 42%, PR in 42%, and Ki-67 in 90%. In eutopic endometria, P450arom was detected in 60% of cases, ER in 60%, and PR in 35%. There were correlations in the steroid-related proteins between the tumors and endometria (P = 0.001-0.026). The positivity of endometrial P450arom (P = 0.04) and ER (P = 0.006) was higher in surviving patients than dead patients regardless of the menstrual state. The results demonstrate correlation between the expression of P450arom, ER, and PR in tumors and eutopic endometria. Intense expression of the steroid-related proteins was associated with better survival.     

Pathobiology of testicular germ cell tumors: views and news

Human germ cell tumors (GCTs) are a heterogeneous group of neoplasms. They can occur in different anatomic locations, predominantly in the gonads (both ovary and testis) and in the midline of the body, including the retroperitoneal, mediastinal and hypothalamus/pineal gland regions. This distribution has been related to the migration routefollowed by primordial germ cells from the yolk sac to the genital ridge. The clinical behavior of these tumors depends on the sex of the patient, the age at clinical presentation and the histology of the tumor, Within the testis, three groups of GCTs can be distinguished; (I) yolk sac tumors and teratomas of neonates and infants; (II) seminomas and nonseminomas of adolescents and adults, the so-called testicular germ cell tumors; and (III) spermatocytic seminomas. This review discusses the histology, epidemiology and chromosomal constitution of GCT, in particular of the seminomas and nonseminomas of the adult testis, including their precursor, carcinoma in situ. In addition, the available data on the molecular basis of treatment sensitivity and resistance of GCT are reviewed.     

The Use of Tumor Registry Data

The End Results Group, sponsored by the National Cancer Institute, coordinates a national cooperative program for evaluating the results of cancer therapy. Three central tumor registries (in California, Connecticut and Massachusetts) plus nine individual hospital registries (in university hospitals) are participating in the program.During the period 1940-59, there was an encouraging increase in five-year survival rates among patients with carcinomas and sarcomas (solid tumors). Preliminary data for 1955-59 suggest that the upward trend is leveling off. A smaller absolute increase in five-year survival rates occurred among patients with lymphomas and leukemia. These increases in patient survival rates coincided with more frequent use of surgical operation for solid tumors and more frequent use of chemotherapy for lymphomas and leukemia.     

Octreotide in the treatment of malignant thymoma – Case report

Thymomas are the most common mediastinal tumors. Systemic therapy for patients with unresectable or recurrent thymomas is a challenging field in the current oncology research. There is some evidence that somatostatin analogs combined with corticosteroids may have a role in the treatment of advanced malignant thymoma; however, the role of these agents have not been fully evaluated.Case reportA 39-year-old man with metastatic thymoma was administered long-acting depot injection form of octreotide. Octreotide scan before the treatment initiation revealed low uptake. CT control after three months of the treatment revealed marked regression of pleural metastases, while the primary tumor mass remained stable. The treatment response was lasting for 9 months.ConclusionWe describe an interesting case of marked clinical and radiological response of advanced malignant thymoma to the treatment with octreotide in a heavily pre-treated patient, even though octreotide scan revealed low uptake.     

Flow cytometry as an accurate tool to complement fine needle aspiration cytology in the diagnosis of low grade malignant lymphomas

S. Schmid, M. Tinguely, P. Cione, H. Moch and B. Bode
Flow cytometry as an accurate tool to complement fine needle aspiration cytology in the diagnosis of low grade malignant lymphomas Objective: Diagnosis of low grade non‐Hodgkin B‐cell lymphomas on cytological material may be problematic and in the past frequently required lymph node excision. We analysed our experience of the value of flow cytometry (FC) as an additional tool for the diagnosis of lymphoproliferative processes in the setting of a university cytology division with a busy fine needle cytology service. Methods: Consecutive cytological specimens with FC over a period of 3 years were retrospectively analysed and correlated with histology and follow‐up if available. FC was performed with the following antibodies: CD3, CD4, CD8, CD2, CD7, CD19, CD5, CD10, CD23, lambda and kappa chains. Results: Of 299 probes (273 fine needle aspirations and 26 fluids from 285 patients), 179 cases (60%) were diagnosed as reactive, 91 cases (30%) as malignant or suspicious and 29 cases (10%) as inconclusive. The results of histological examination of the lymph nodes were available in 41 of 91 (45%) malignant or suspicious cases and in 13 of 179 (7%) reactive cytological diagnoses. Cytologically diagnosed malignancy was confirmed in all histologically examined cases. In 12 of 13 reactive cytological cases (92%), a benign process was diagnosed histologically. In 34 of 299 cases (11%) additional molecular investigations of B‐cell clonality or specific translocations were performed. The lymphomas most frequently diagnosed were follicular lymphoma and lymphocytic lymphoma, followed by mantle cell and marginal zone lymphomas. Correlation with histology showed a sensitivity of 98% and a specificity of 100% for cytology in our series. Conclusions: FC is an important additional tool in the cytological diagnosis of lymphoproliferative disorders. The combined approach has a high diagnostic value that allows a reliable subclassification of low grade B‐cell non‐Hodgkin lymphomas.     

Bilateral germ cell testicular tumors

PURPOSE: To study the clinical characteristics of bilateral testicular tumors in the cisplatin era. PATIENTS AND METHODS: Between November 1988 and November 1998 2386 testicular cancer patients were treated in our Department and 72 bilateral germ cell testicular cancer patients were retrospectively explored (3%). The incidence, the clinical and histological characteristics and, in the case of asynchronous tumor, the interval between the two tumors were analyzed. RESULTS: During the 10 years 19 synchronous (26.4%) and 53 asynchronous bilateral germ cell testicular cancers (73.6%) were treated. The incidence of bilateral synchronous seminoma was 68.4%. Among the asynchronous tumors 9 concordant seminomas and 9 concordant nonseminomas were detected. In the first, second and third 5-year follow-up period 39.6, 30.2, and 28.2% of asynchronous tumors were diagnosed. The incidence of seminoma after the first castration in the 5, 10 and 15 years was 19, 37.5, and 60%, respectively. The overall survival rates of synchronous and asynchronous testicular cancer were 84 and 93%. In cases of asynchronous tumor the prevalence of stage I cancer was significantly greater in a regularly controlled population (p=0.014) than in the not regularly followed population, but the survival rate was good in both groups. Nonseminoma showed up earlier as first and second tumor than seminoma (p=0.05, p=0.045). The interval between the two asynchronous tumors was shorter in the case of nonseminoma than in the case of seminoma (p=0.002). CONCLUSION: The prognosis of bilateral germ cell testicular cancer is good because of the high incidence rate of seminoma and the effective treatment. With regular follow-up the early diagnosis of second testicular tumors is probable. The interval between the tumors depends on the patients' age and the histology of the second tumor, in the case of seminoma it is longer. The effect of the previous treatment on the incidence of seminoma and the interval between the two asynchronous tumors requires further investigations.     

Fine needle aspiration of metastatic and hematologic malignancies clinically mimicking pancreatic carcinoma.

The fine needle aspiration (FNA) cytology findings in 19 cases of hematopoietic and metastatic neoplasms that radiographically mimicked primary pancreatic carcinoma are reported. These cases represented 11% of 176 malignant diagnoses in a series of 304 pancreatic FNAs. The cytologic diagnoses included 7 non-Hodgkin's lymphomas, 2 Hodgkin's lymphomas, 6 small cell carcinomas (4 lung, 1 gallbladder, 1 skin), 3 squamous cell carcinomas (2 cervix, 1 esophagus) and 1 hepatocellular carcinoma. In six cases the pancreatic lesion was the initial presentation of malignant disease. These included five lymphomas, which probably involved peripancreatic lymph nodes, and a metastatic small cell carcinoma of pulmonary origin. Recognition of unusual morphologic features of pancreatic carcinoma raised the possibility of extrapancreatic malignancies. Electron microscopy and immunocytochemistry performed on FNA specimens were helpful in selected cases. The FNA diagnosis of hematopoietic and metastatic neoplasms that clinically mimic pancreatic carcinoma prompts appropriate clinical studies and treatment and eliminates the need for open pancreatic biopsy and/or resection.