Cytology of pancreatic acinar cell carcinoma

Acinar cell carcinoma (ACC) of the pancreas is extremely uncommon and its cytologic features have rarely been described. We describe the cytologic features of cases we have seen, review the literature regarding its cytologic features and discuss the pitfalls that may be encountered and the use of immunohistochemistry for its diagnosis. We searched our databases for all cases of histologically confirmed pancreatic ACC which had undergone prior fine needle aspiration (FNA) of the primary pancreatic lesion. The clinical histories, radiographic and sonographic findings, cytologic features, original cytologic diagnoses, and final histologic diagnoses were reviewed. Four cases of pancreatic ACC were found that had undergone FNA prior to histologic confirmation of the diagnoses. They were from 2 men and 2 women aged 50-75 yr. All masses were in the head of the pancreas, 2 had apparent peri-pancreatic adenopathy and 1 had an apparent liver metastasis. On review, all 4 had had diagnostic material on cytology samples. Original cytologic diagnoses included "acinar cell carcinoma," "pancreatic endocrine tumor," "favor neuroendocrine tumor, low-grade" and "non-diagnostic specimen." The cytologic features included small to moderate-sized loose groups with numerous single cells, prominent acinar formation, little anisonucleosis and prominent nucleoli. The cytologic features showed significant overlap with those of pancreatic endocrine tumors.     

Diagnostic approach to pancreatic tumors with the specimens of endoscopic ultrasound‐guided fine needle aspiration

Endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) has enabled clinicians to histologically diagnose pancreatic tumors. However, EUS‐FNA specimens often result in tiny fragmented tissues, so auxiliary utilities are necessary. Using immunostaining of CK7, CDX2, neuroendocrine markers and KRAS mutation analysis, we examined 57 FNA cell block sections and 61 surgically‐resected specimens (25 invasive ductal carcinomas, 25 endocrine tumors, and 11 acinar cell tumors). In the majority of the matched pairs, the diagnoses between EUS‐FNA and surgical specimens were concordant using the following criteria: neuroendocrine markers negative, CK7 positive, and mutated KRAS gene for invasive ductal carcinomas; neuroendocrine markers diffusely positive, CK7 and CDX2 negative, and wild‐type KRAS gene for well‐differentiated endocrine tumors; and neuroendocrine markers no more than focal positive, CK7 and CDX2 with various staining patterns, and wild‐type KRAS gene for acinar cell carcinomas. Expression of CK7 and/or CDX2 in addition to KRAS mutations were occasionally seen in endocrine carcinomas, but not in well‐differentiated endocrine tumors, suggesting that ductal differentiation in an endocrine tumor may be a predictor of aggressive disease. The usefulness of these markers was confirmed using 13 additional pancreatic tumors, prospectively. Although minimal in selection, these markers are helpful in making diagnosis from EUS‐FNA specimens of the major pancreatic tumors.     

The cytopathology of soft tissue mxyomas: ganglia, juxta-articular myxoid lesions, and intramuscular myxoma

We studied the practicality of issuing a cytologic diagnosis of myxoma/juxta-articular myxoid lesion/ganglion (MJG) by reviewing all fine-needle aspiration (FNA) biopsy specimens of soft tissue masses in our files with diagnoses of myxoma, myxoid cyst, myxoid lesion, ganglion, or ganglion cyst. The control group was soft tissue aspirates with abundant myxoid stroma. Of 39 cases with a cytologic diagnosis of soft tissue MJG, 15 had subsequent tissue biopsy or complete resection of the mass; 24 had clinicoradiologic follow-up. All cases except 1 (fat necrosis) were diagnosed correctly as benign myxoid lesions. We grouped MJG aspirates into 3 subtypes based on clinicoradiologic features: soft tissue ganglion/ganglion cyst (12 cases), juxta-articular myxoid lesion (16 cases), and intramuscular myxoma (11 cases). MJG aspirates showed few, subtle cytopathologic differences among subtypes. They characteristically had a viscous, gelatinous quality when expressed from the needle onto the glass slide. The typical smear contained a film of paucicellular, often finely granular, myxoid stroma, that contained few cells, usually macrophages or bland spindle cells. Control group aspirates always contained cellular components that allowed distinction from MJGs. The cytopathologic diagnosis of MJG lesions is accurate; FNA biopsy can be used to subtype MJGs into 3 categories when clinicoradiologic features are known.     

Pancreatic fine‐needle aspiration cytology in patients < 35‐years of age: A retrospective review of 174 cases spanning a 17‐year period

Pancreatic lesions in young patients are relatively rare and, to our knowledge, the clinical value of pancreatic fine needle aspiration (FNA) in patients < 35 years of age has not been previously established by any other large retrospective studies. All pancreatic endoscopic ultrasound‐guided FNA (EUS‐FNA) cases performed on patients < 35 years of age were identified for a 17‐year period (1994–2010). All FNAs and all available correlating surgical pathology reports were reviewed. There were a total of 174 cases of pancreatic FNA performed on 109 females and 65 males under the age of 35 (range: 8–34, mean: 27 years). The FNA diagnoses included 37 malignant, 114 negative, nine atypia/suspicious, and 14 cases that were nondiagnostic. Of the 37 malignant FNA cases, the diagnoses included 18 pancreatic neuroendocrine tumors (PanNeT), 11 solid pseudopapillary neoplasms (SPN), five adenocarcinomas and three metastatic neoplasms. Histologic follow‐up was available in 22 of the 37 malignant cases diagnosed by FNA, and the diagnosis was confirmed in 21 cases. One pancreatoblastoma was misclassified as SPN on EUS‐FNA. False negative diagnoses were noted in three cases of low‐grade mucinous cystic neoplasm and one case of PanNeT. The most common type of neoplasms diagnosed by EUS‐FNA in patients < 35‐year old is PanNeT, followed by SPN with both tumors accounting for 75% of all the neoplasms encountered in this age group. The sensitivity and specificity for positive cytology in EUS‐FNA of the pancreas to identify malignancy and mucinous neoplasms were 90% and 100%, respectively. Diagn. Cytopathol. 2014;42:297–301. © 2013 Wiley Periodicals, Inc.     

Cytologic differential diagnosis of myxoid and mucinous neoplasms of the sacrum and parasacral soft tissues

A diagnostically important group of lesions involving the sacrum, spinal canal, and parasacral soft tissues is characterized by a myxoid or mucinous background in cytologic smears. This group of myxoid/mucoid neoplasms includes chordoma, myxopapillary ependymoma, metastatic mucinous adenocarcinoma, and extraskeletal myxoid chondrosarcoma. Despite the similarity of the background substance, each neoplasm within this differential diagnosis has a characteristic composite set of morphologic and immunophenotypic features. Because many of these masses are not easily surgically biopsied, fine-needle aspiration (FNA) is often used for their diagnosis. The private consultation records of the author and the cytology files of the University of Utah Department of Pathology were searched for all lesions arising in or around the sacrum. These cases were reviewed to determine which had a myxoid/mucinous background. Fourteen neoplasms were found and comprise the study set. Four of these cases had cell block material in addition to Diff-Quik-stained smears; a panel of antibodies, including cytokeratin, glial fibrillary acid protein (GFAP), S-100 protein, and carcinoembryonic antigen (CEA), was performed on the cell block material. The smears were evaluated for cytologic features, including the presence of rosette-like structures, physaliphorous cells, gland-like structures, chondroid fragments, "signet ring" and "goblet" cells, as well as the character of the myxoid/mucinous background substance.The cases included one myxopapillary ependymoma, 10 chordomas, two mucinous adenocarcinomas of colonic or gastric origin, and one myxoid chondrosarcoma. Physaliphorous cells were found to be highly specific for chordoma, while a fibrillary myxoid stroma containing cells with elongated cytoplasmic processes and cells lying in a rosette-like pattern around central cores of myxoid to fibrillary stroma were highly characteristic of myxopapillary ependymoma. Fragments of a myxoid/chondroid matrix with lacunar-like spaces strongly supported the diagnosis of myxoid chondrosarcoma. "goblet" or "signet ring" cells with a single distinct vacuole favored mucinous adenocarcinoma. There appear to be sufficient cytomorphologic features present within the FNA smears and cell block material to allow cytologic separation of the more common myxoid and mucinous neoplasms involving the sacral and parasacral tissues.     

Fine-needle aspiration cytology of pancreatic somatostatinoma: the importance of immunohistochemistry for the cytologic diagnosis of pancreatic endocrine neoplasms

Pancreatic somatostatinoma is a rare pancreatic endocrine neoplasm representing as little as 1% of pancreatic endocrine neoplasms (PENs). The histologic features of this tumor are like those of other PENs, except that it commonly forms acinar structures and often has cells with abundant, granular cytoplasm. We have recently encountered two of these neoplasms sampled by endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA). We discuss the cytologic and immunohistochemical findings of these two cases and the cytologic similarities these neoplasms share with pancreatic acinar-cell carcinoma (PACC). We review the cytologic features of PEN and PACC and discuss the importance of cell block immunohistochemistry in the diagnosis of pancreatic neoplasia sampled by EUS-guided FNA.     

Fine‐needle aspiration in myxofibrosarcoma: Experience of Institut Curie

Myxofibrosarcoma (MFS) is a well‐established nosologic entity different from the myxoid variant of malignant fibrous histiocytoma. In an attempt to better define the representative cytologic criteria of MFS, we undertook a review and a reanalysis of a series of 14 cytology samples in 12 patients whose tumors were diagnosed as MFS. Using FNA technique and reviewing the original diagnoses, 11 cases were diagnosed as malignant and three as benign tumors. The cytologic diagnosis of MFS was accurate in seven cases (2 primary tumors, 4 recurrences, and 1 metastasis). Four cases were classified malignant myxoid sarcoma (1 primary and 3 recurrences), whereas three cases (2 primary and 1 recurrence) were false‐negative. The smears were cell‐rich in 12 cases and cell‐poor in two cases. They were constantly composed of isolated and regular small spindle‐shaped and stellated cells with elongated nuclei containing small inconspicuous nucleoli. Cytoplasm was pale with elongated processes. Clusters of wavy spindle‐shaped cells, round cells without specific pattern, moderate cytonuclear atypia, and abundant myxoid background as well as curvilinear vascular structures were always seen. In the vast majority of cases, the cytologic distinction of MFS from other low‐grade myxoid lesions is difficult. Entities such as myxoid MFH, myxoid liposarcoma (MLP), myxoid DFSP, and myxoma should be considered in the differential diagnosis. The cytological misdiagnosis is of limited clinical consequence because FNA findings suggestive of a myxoid tumor will be indicative for a surgical removal followed by the histopathological analysis. Diagn. Cytopathol. 2010. © 2009 Wiley‐Liss, Inc.     

Cytological diagnosis of endocrine tumors of the pancreas by endoscopic ultrasound-guided fine-needle aspiration biopsy

The aim of this study was to evaluate the efficacy and accuracy of endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) in the diagnosis of pancreatic endocrine tumors and to analyze their cytomorphology. Between March 1999 and June 2004, a total of 30 patients with a cytological diagnosis of pancreatic endocrine tumors were found. Their records were retrieved and the cytological materials were analyzed. The mean size of the tumors assessed by EUS was 3.0 cm. Immediate preliminary interpretation was rendered after an average of 1.5 passes. Based on the cellular patterns, cases were divided into three categories: loosely cohesive aggregates, discohesive single cells, and cohesive flat sheets. Most tumor cells had abundant cytoplasm and eccentric nuclei. Chromatin was fine or coarse but was evenly distributed in all cases. Nuclear pleomorphism, multinucleation, intranuclear inclusions, mitotic figures, and necrosis were seen. Immunohistochemical (IHC) studies on cell blocks confirmed the diagnosis in all cases. EUS-guided FNA is efficient and accurate in establishing the diagnosis of pancreatic endocrine tumors. The variety of cellular patterns presents several differential diagnostic issues that should be considered to avoid erroneous interpretation.     

Extraskeletal myxoid chondrosarcoma of the nasopharynx

Extraskeletal myxoid chondrosarcoma is a rare but distinct entity with special clinicopathological, immunohistochemical, cytogenetical and outcome features. This tumor developed from soft tissues. A few cases have been reported in the head and neck in the literature. We report two new cases of extraskeletal myxoid chrondrosarcoma presenting in such an unusual site: one involved the left nasal cavity of a 67-year-old man and the second the sphenoidal sinus of a 71-year-old woman. The microscopic examination revealed nests of round small cells dispersed in a myxoid stroma. The myxoid material was stained with Alcian Blue with and without hyaluronidase application whereas no PAS staining was observed. The immunohistochemical staining showed reactivity with S-100 protein and vimentin in two cases and with EMA in one case. These results allowed us to exclude other differential diagnoses: soft tissue tumors with a myxoid stroma (myxoma, myxoid liposarcoma and myxofibrosarcoma). No staining with anti-KL1 allowed us to exclude chordoma. Curative surgery was not possible. Both patients were given radiotherapy and the tumor regressed in one.     

Diagnosis of nonprimary pancreatic neoplasms by endoscopic ultrasound-guided fine-needle aspiration

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a proven modality for the diagnosis of primary pancreatic neoplasms. We describe our experience in diagnosing nonprimary pancreatic tumors by EUS-FNA. Cytology files were searched for all EUS-FNA of the pancreas for the period 2000-2002. All cases diagnosed as neoplasms were selected and those diagnosed as nonprimary pancreatic tumors were reviewed and analyzed. One hundred ninety-one of 468 cases were diagnosed as neoplasms. Eleven of these cases were diagnosed as nonprimary pancreatic tumors (2.4% of all diagnoses and 5.7% of all neoplasms). The diagnoses were supported by clinical history (n = 7), cytological findings (n = 11), cell block histology (n = 11), cell block immunohistochemistry (n = 6), and flow cytometry (n = 1). EUS-FNA is a safe and minimally invasive method for the diagnosis of nonprimary pancreatic neoplasms. Evaluation of clinical history, cytomorphology, and ancillary techniques, especially those applied to cell block material, are essential for accurate diagnoses.     

Exfoliative sputum cytology of cancers metastatic to the lung

Although largely replaced by fine-needle aspiration (FNA) and bronchoscopy, cytological examination of sputum for exfoliated malignant cells still is considered a valuable initial diagnostic test in patients presenting with a lung mass. Thirty-five cases of secondary/metastatic tumors involving the lung and diagnosed on sputum were retrospectively reviewed from our cytopathology files for a period of 22 yr (1980-2001). Clinical history and the relevant histopathological material were examined and correlated with the cytological findings. In all cases, a history of malignancy was known. Cytological diagnoses included colonic adenocarcinoma (7 cases); non-Hodgkin's lymphoma (NHL; 5 cases); malignant melanoma (MM; 5 cases); breast carcinoma (5 cases); Hodgkin's lymphoma (HL; 3 cases); pancreatic adenocarcinoma (2 cases); prostatic adenocarcinoma (2 cases); and 1 case each of urothelial carcinoma, endometrial carcinoma, renal cell carcinoma, hepatic small-cell carcinoma, squamous-cell carcinoma (cervix), and leiomyosarcoma (LMS). Cellular preservation was optimal in all cases. The smear background was relatively clean in 25 (71%) cases and predominantly inflamed and/or necrotic in 10 (29%) cases. In non-lymphoid tumors (27 cases), isolated single malignant cells were seen in 7 (26%) cases (all cases of MM and prostatic adenocarcinoma), whereas 20 (74%) cases displayed fragments with intact tumor architecture. Overall, only 10/35 (29%) cases showed noticeable tumor-cell necrosis. In one case (LMS), cell block sections were used for immunoperoxidase (IPOX) studies with positive staining for desmin and actin. Exfoliation of cancer cells in sputum from secondary tumors in the lung is a rare phenomenon in current-day practice, with metastatic colonic adenocarcinoma seen most commonly. Intact tumor architecture was observed in exfoliated cells in 75% of the cases.     

Primary pancreatic lymphoma evaluated by fine-needle aspiration: findings in 14 cases

Fine-needle aspiration (FNA) is a popular method for evaluating pancreatic lesions. There is considerable literature on FNA evaluation of primary pancreatic carcinomas, but few studies address the FNA diagnosis of primary pancreatic lymphoma. We reviewed 14 cases of atypical lymphoid processes diagnosed by FNA during a 5-year period, constituting 1.3% of a total of 1,050 pancreatic FNA cases. The diagnoses were as follows: 6 large B-cell lymphomas, 4 follicular lymphomas, 3 suggestive of lymphoma, and 1 unclassified B-cell lymphoma. Lymphoid neoplasms manifested in older people (mean age, 64.7 years) as a solitary mass in the pancreatic head, mimicking primary carcinoma. Clonality was confirmed by flow cytometry in 11 cases and immunohistochemical analysis on cell block material in 2. Obtaining diagnostic material often required several passes (average, 3.9 passes; range, 1-8 passes). We conclude that primary pancreatic lymphomas rarely are diagnosed by FNA, tend to be high grade, and clinically and radiographically might mimic primary carcinoma.     

Sampling of the adrenal glands by endoscopic ultrasound-guided fine-needle aspiration

Endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) has proven to be a valuable modality for the primary diagnosis and staging of gastrointestinal, and perigastrointestinal malignancy. Aside from assessing thoracic and abdominal lymph nodes and the liver for metastases, EUS can assess and sample the adrenal glands, which are frequently involved by metastatic disease, but can also harbor benign primary neoplasms. The cytology files at our institution were reviewed for all cases of EUS-guided FNA of the adrenal glands. Clinical histories, sonographic findings, and cytologic findings of all cases were reviewed. Results were compared with overall EUS-guided FNA performance and the performance of non-EUS-guided FNA of the adrenal. The utility of cell block immunohistochemistry (IHC) in these cases was reviewed. Between 1/1/00 and 5/15/04 there were 24 cases of EUS-guided FNA of the adrenal gland from 22 different patients (13 men; 9 women) at our institution. This represented 1.4% of overall EUS-guided FNA and 77% of adrenal gland FNA. Patient ages ranged from 37 to 86 yr (mean 69 +/- 11 yr). Most patients had other cancers or mass lesions and were being staged at the time of the procedure (19 of 22). Almost all FNAs were of the left adrenal gland (23 of 24). Lesion size ranged from 0.9 to 7.9 cm (mean 2.5 +/- 1.6 cm). Diagnostic material was present in all cases when compared with an overall EUS-guided FNA diagnostic rate of 88%. Material for cell block was present in 21 cases, and IHC was used in 3 cases. Final diagnoses were as follows: cortical tissue consistent with cortical adenoma (19), metastatic adenocarcinoma (3), pheochromocytoma (1), and adrenal cortical carcinoma (1). EUS-guided FNA of the adrenal gland is primarily used in the staging of other malignancies when lesions of the left adrenal are recognized sonographically. Diagnostic tissue is easily obtained, including material for cell block IHC, which allows definitive diagnosis in cases that present difficult differential diagnoses.     

Cytopathologic analysis of paraspinal masses: a study of 59 cases with clinicoradiologic correlation

Paraspinal masses (PSM) are uncommon and present a wide spectrum of differential diagnoses on fine-needle aspiration (FNA). We analyzed 59 cases of PSM on FNA in a 15-yr period, in the context of clinicoradiologic correlation. Radiologic findings, clinical data, and tissue biopsies were reviewed. Patients were 14-83 yr of age (mean 54.7) with a M:F ratio of 1.36:1. Of the 59 cases, 39 (66%) were deemed diagnostic. Of these, 8 (21%) revealed nonneoplastic lesions and 31 (79%) yielded neoplasms: 2 (6%) benign and 29 (94%) malignant. Of the malignant cases, 22 (76%) were metastatic tumors from various sites, while 7 (24%) were cancers from local spread, which included non-Hodgkin's lymphoma (NHL, 5) and myeloma (2). Benign neoplasms were nerve sheath tumors. Metastatic tumors consisted of adenocarcinoma, 9; squamous-cell carcinoma, 3; renal-cell carcinoma, 1; and non-small-cell carcinoma/not otherwise specified (NOS), 9. Twenty-four (41%) cases received further studies: immunoperoxidase (IPOX) alone, 17 (71%); special stains for microorganisms, 2 (8%); IPOX/other special stains, 4 (17%); and flow cytometry analysis, 1 (4%). Eight (14%) cases received follow-up biopsies. Half of these biopsies added information to previously "nondiagnostic" FNAs. Of the previously "diagnostic" FNAs, tissue biopsy yielded no additional information. Cytopathologic diagnoses were consistent with the pre-FNA radiology analyses in 13 (39%) cases. In instances of radiologic and cytopathologic discrepancy (4 cases, 12%), diagnoses made by FNA reversed the initial radiologic impression of neoplasm to infection, and vice versa. PSMs are rare lesions (0.26% of total FNAs done in 15 yr at our institution). The most common lesion encountered is metastatic adenocarcinoma, followed by NHL. Ancillary studies are helpful in difficult cases. In cases of radiologic/cytopathologic discrepancy, FNA diagnoses are more accurate and decisive for patient management. The sensitivity and specificity of a PSM FNA are 88% and 75% respectively.     

儿童胰腺实性假乳头状瘤多排螺旋CT表现

目的:探讨儿童胰腺实性假乳头状瘤（SPTP）的多排螺旋CT（MDCT）表现。 方法:回顾性分析经手术病理证实为SPTP的10例患儿临床及MDCT资料,分析总结其特征表现。 结果:10例患儿均为女性,SPTP均为单发病灶,位于胰腺头颈部3例,胰腺体尾部7例。肿瘤最大径为2.5~13.8 cm,平均值为5.94 cm。8例呈类圆形,2例呈分叶状。10例均边界清晰,8例有完整包膜。平扫1例肿瘤呈均匀低密度,增强无明显强化;其余9例呈囊实性,8例以实性为主,1例囊实性比例相当,其中1例可见包膜下弧形钙化,实性成分动脉期呈轻度强化,强化程度低于正常胰腺组织,门脉期呈渐进性不均匀强化,囊性成分无强化。1例肿瘤出现肝内胆管和主胰管轻度扩张,1例出现主胰管轻度扩张。所有肿瘤均未见肝脏及淋巴结转移。 结论:儿童SPTP好发于女性,其CT表现具有一定的特征性,对诊断和鉴别诊断具有一定意义。     

Pitfalls in the diagnosis of adult rhabdomyoma by fine needle aspiration: Report of a case and a brief literature review

Fine needle aspiration (FNA) is a valuable, noninvasive, commonly used technique in the diagnoses of head and neck tumors. Adult rhabdomyoma is a rare benign tumor of striate muscle tissue usually located in the head and neck region. Cytomorphologically, the tumor cells have eosinophilic finely granular cytoplasm, which sometimes can mimic other tumors. We report a case of adult rhabdomyoma, which was initially misinterpreted as granular cell tumor on FNA biopsy due to lacking of typical cytological features of adult rhabdomyoma. We recommend that adult rhabdomyoma should be included in differential diagnoses when the cytological features are suggestive of granular cell tumor. A panel of immunohistochemical stains including S100, desmin, and myoglobulin may also be helpful in making correct diagnosis. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.     

Fine needle aspiration of malignant melanoma with myxoid features: A case report with molecular analysis

Malignant melanoma with myxoid features (MMM) is a rare melanoma variant in which tumor cells are embedded within a basophilic myxoid stroma. The stromal matrix is composed of acidic mucopolysaccharides, which are thought to be produced by mesenchymal stromal cells in response to melanoma invasion. Interestingly, this myxoid matrix is more often seen in metastasis from a primary tumor that does not have a myxoid stroma. The diagnosis of MMM on fine needle aspiration (FNA) can be confused with other myxoid tumors. Herein, we present a case of MMM diagnosed by FNA of a peri‐auricular lymph node in an 89‐year‐old man with a history of resected malignant melanoma. We describe the clinical, cytohistological, and immunohistochemical findings, and present the unique molecular alterations that were identified. We also discuss the differential diagnosis and potential diagnostic pitfalls associated with MMM.     

CD34+ fibrocytes in neoplastic and inflammatory pancreatic lesions

Besides its function as a matrix-producing cell, the CD34+ fibrocyte has been reported to be an antigen-presenting cell capable of priming naive T cells in situ. Therefore, it has been claimed that the CD34+ fibrocyte may play an important role in host response to tissue damage. The objective of the present study was to analyze the presence and distribution of CD34+ fibrocytes and smooth muscle actin (SMA) reactive myofibroblasts in relation to the underlying pancreatic disease. We investigated a total of 12 pancreatic adenocarcinomas, 7 endocrine tumors of the pancreas, and 8 cases of chronic pancreatitis; in 11 cases, normal pancreatic tissue was available. The stroma of normal pancreatic tissue harbored diffusely scattered CD34+ fibrocytes. Chronic pancreatitis was characterized by an increased number of stromal CD34+ fibrocytes paralleled by a gain of SMA reactive myofibroblasts which were not observed in the normal pancreatic stroma. The stroma of pancreatic ductal adenocarcinomas and endocrine tumors was devoid of CD34+ fibrocytes or showed at least a focal loss of this cell type, whereas SMA reactive myofibroblasts were detected in both endocrine tumors and adenocarcinomas. We conclude that detection of CD34+ fibrocytes may constitute an adjunctive tool in distinguishing chronic pancreatitis from ductal adenocarcinoma since the absence of this cell population strongly favors a neoplastic process. Moreover, CD34+ fibrocytes and myofibroblasts appear to be involved in stromal remodeling associated with chronic pancreatitis and ductal adenocarcinoma.     

Primary pancreatic leiomyosarcoma with metastasis to the liver diagnosed by endoscopic ultrasound‐guided fine needle aspiration and fine needle biopsy

Primary pancreatic leiomyosarcomas are rare tumors of the pancreas that are usually diagnosed after resection or by biopsy. One case in the literature has utilized endoscopic ultrasound‐guided fine needle aspiration (EUS‐FNA) cytology. We report a second case of a primary pancreatic leiomyosarcoma that yielded diagnostic material on EUS‐FNA cytology. A 72‐year‐old female presented with 3–4 months of abdominal pain. A CT scan showed a large heterogeneous, lobulated pancreatic head and uncinate mass and multiple hypoattenuating liver lesions. An EUS‐FNA was performed on one of the liver lesions with a 25‐gauge needle, yielding an adequate sample with lesional cells. The initial read was a spindle cell neoplasm. A subsequent endoscopic ultrasound‐guided fine needle biopsy with a 22‐gauge needle was performed on the pancreatic head mass to rule out two primaries and to provide tissue for a mitotic index in the case of gastrointestinal tumor. Both the cell block of the EUS‐FNA and the core biopsy were equally cellular and showed interlacing spindle cells that stained positive for SMA and negative for DOG‐1, CD 117, and CD34. In addition, the core biopsy of the pancreas stained positive for Desmin. A diagnosis of a primary pancreatic leiomyosarcoma was made and the patient was started on systemic chemotherapy. Primary pancreatic leiomyosarcomas are rare pancreatic tumors that may yield diagnostic material by EUS‐FNA with a 25‐gauge needle. Diagn. Cytopathol. 2016;44:1070–1073. © 2016 Wiley Periodicals, Inc.