UNASSIGNED: Pancreatic schwannoma (PS) is an extremely rare benign tumor. Here we describe the Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) results of PS in a 59 years old woman, as well as a review of the literature.
UNASSIGNED: A 59-year-old woman consulted for atypical epigastralgia without fatigue, weight loss or fever. CT scan and MRI showed a 35 mm inhomogeneous lesion with well-defined margins located in the pancreas head. The diagnosis of pancreatic tumor was made. The pathologic examination of the biopsied mass yielded a diagnosis of pancreatic schwannoma.
UNASSIGNED: On CT scans, almost all benign PS are well-defined cystic or low-density masses. MRI is helpful in characterizing their typical encapsulation.
UNASSIGNED: The detection of pancreatic schwannoma is extremely rare. Although multiple imaging modalities are currently available, it is challenging to make an accurate diagnosis before operation.

Although primary pancreatic lymphoma is a rare cause of pancreatic mass, this diagnosis should be considered during work-up. Furthermore, when adequate diagnostic material is available from biopsy, complete workup of the lymphoma, including not only type but also subtype when applicable, should be performed.

Isolated pancreatic tuberculosis (PT) is an extremely rare disease, with non-specific clinical characteristics, making the diagnosis often challenging with pancreatic cancers. Here we report a case of a 36-year-old female, who was admitted to our hospital after suffering from a 3-month history of epigastric abdominal pain, night sweats and weight loss. The physical examination was normal. The radiological findings revealed the presence of a pancreatic mass and multiple abdominal lymphadenopathy, suggestive of malignancy. The initial differential diagnosis suspected was pancreatic tuberculosis. Tuberculosis skin test was performed and was highly positive (>22 mm). Computed tomography (CT)-guided biopsy of peripancreatic lymph node was carried out and the histopathological exam confirmed the diagnosis of PT. Therefore, anti-tuberculous therapy was initiated, leading to clinical and radiological improvement. The diagnosis of PT is rare and can sometimes be misleading. It should be considered when a pancreatic mass is observed, especially in endemic countries, to ovoid unnecessary interventions.

Although pancreatic tuberculosis (TB) is traditionally considered to be a rare clinical entity, in recent times, an increase in the number of reports of pancreatic TB has been noted. We conducted a systematic review in order to summarise currently available data on pancreatic TB.
A comprehensive literature search of Medline, Scopus and ISI Web of Science databases was conducted in order to identify papers reporting cases of pancreatic TB. The eligibility criteria for inclusion in the review required that the studies reported patient(s) affected by pancreatic TB and that individual data on age, sex, clinical presentation and outcome were available.
In total, 116 studies reporting data on 166 patients were included in the analysis. The majority of patients were males (62.1%) diagnosed at a mean age of 41.61 ± 13.95 years. Most cases were diagnosed in Asia (50.0%), followed by North America (22.9%), Europe (20.5%), Africa (4.2%) and South America (2.4%). Human immunodeficiency virus (HIV) infection was diagnosed in 25.3% of those affected. Pancreatic TB most frequently presented itself in the form of a pancreatic mass (79.5%) localised mainly in the head (59.0%) and less frequently in the body (18.2%) and tail (13.4%). Extrapancreatic TB involvement most frequently affected the peripancreatic lymph nodes (47.3%). More than half of patients (55.2%) were subjected to laparotomy, while 21.08% underwent endoscopic ultrasound fine-needle aspiration biopsy. The presence of TB was identified most frequently through histological analysis (59.6%), followed by culture (28.9%), staining (27.7%) and, in a smaller number, by polymerase chain reaction (9.6%) and cytology (6.6%). Almost all patients received anti-tubercular pharmacological therapy (98.2%), while 24.1% underwent surgery. Despite treatment, 8.7% of patients died.
Increased awareness of pancreatic TB is needed, not only in endemic areas but especially in relation to HIV infection and other clinical conditions associated with immunoincompetence.

Understanding the difference between malignant and benign pancreatic masses is critical in terms of diagnosis, although this is difficult to determine in clinical practice. The contrast-enhanced harmonic endoscopic ultrasound (CH-EUS) technique was introduced in 2010, although, to the best of the authors\' knowledge, there has been no systematic review or meta-analysis to date evaluating its diagnostic performance for the differentiation of pancreatic masses. The aim of the present study was to systematically evaluate the diagnostic performance of CH-EUS for the differentiation of pancreatic masses. Search key words and inclusion and exclusion criteria were initially presented. Two independent authors read and extracted the relevant information from the included studies. Disagreements were resolved through discussion with another two experienced authors. Metadisc and Stata software were used for the meta-analysis and the evaluation of bias. A total of 16 studies comprising 1,325 patients were included in this meta-analysis. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio of CH-EUS were used to distinguish between malignant and benign tumors, and the values obtained were 93% [95% confidence interval (CI): 91-94%], 84% (95% CI: 80-87%), 5.58 (95% CI: 3.90-7.97), 0.09 (95% CI: 0.07-0.11) and 72.56 (95% CI: 48.93-107.60), respectively. The area under the summary receiver operating characteristic curve was determined to be 0.96. No publication bias was identified in this meta-analysis. Taken together, these results confirm that CH-EUS has a high accuracy rate for distinguishing between benign and malignant pancreatic space-occupying lesions, and it may therefore be used as an effective diagnostic tool for pancreatic masses.

BACKGROUND: Intrapancreatic accessory spleen (IPAS) is an uncommon finding of pancreatic mass. Differential diagnosis with pancreatic tumor, especially with non-functional neuroendocrine tumor (NF-NET), may be very hard and sometimes it entails unnecessary surgery. A combination of CT scan, MRI, and nuclear medicine can confirm the diagnosis of IPAS. 68-Ga-Dotatoc PET/CT is the gold standard in NET diagnosis and it can allow to distinguish between IPAS and NET.
METHODS: A 69-year-old man was admitted to our hospital for an incidental nodule in the tail of the pancreas with focal uptake of 68-Ga-dotatate at PET/CT. NET was suspected and open distal splenopancreatectomy was performed. Pathologic examination revealed an IPAS.
CONCLUSIONS: This is the second IPAS case in which a positive 68Ga-Dotatoc uptake led to a false diagnosis of pancreatic NET. Here is a proposal of a literature review.

BACKGROUND: Castleman disease (CD) is a rare polyclonal lymphoproliferative disorder of unknown etiology, which usually develops in the mediastinum. It can also occur in the cervical, retroperitoneal and axillary regions. Localized pancreatic CD is quite rare [1].
METHODS: The authors herein present a case of a 34 years old female that was diagnosed during a symptomatic cholelithiasis evaluation. During the evaluation, an abdominal ultrasonography revealed a tumor at the head of the pancreas, which went on to generate a dilatation of the extrahepatic bile ducts. This finding was confirmed by abdominal magnetic resonance imaging (MRI). Subsequently, the patient underwent a laparotomy, where a capsulated tumor was found at the head of the pancreas with well-defined margins. The decision was made for tumor excision. The histopathology and immunohistochemistry established CD, hyaline vascular variation.
CONCLUSIONS: The authors of the present paper also performed a literature review concerning Pancreatic CD, where there were found only 33 cases until the time of the writing of this paper, and we have subsequently carried out a retrospective analysis of all cases. In a patient with atypical images, there might be a benefit from a preoperative diagnosis of CD, by using immunohistochemistry analysis in an image guided biopsy. Thus, avoiding unnecessary procedures and surgeries.
CONCLUSIONS: Localized pancreatic CD is a very rare condition with good prognosis, but it can mimic many common diseases, such as gastrointestinal stromal tumor (GIST), pancreatic neuroendocrine tumor or pancreatic adenocarcinoma.

BACKGROUND: Accessory spleens located within the pancreatic parenchyma (intrapancreatic accessory spleen, IPAS) pose a unique clinical challenge. In many cases, despite imaging and other diagnostic studies, malignancy cannot be excluded and patients are subjected to pancreatic resection. We review our experience with the presentation, diagnosis, and treatment of patients with IPAS to provide insight into improving pre-operative evaluation of these patients METHODS: A retrospective chart review identified seven patients who underwent surgical resection of an intrapancreatic spleen at University of Louisville Hospital between 2004 and 2015. Charts were analyzed for presenting symptoms, pre-operative imaging, operative therapy, and final pathologic evaluation. Patients were included in the study if they underwent pancreatic resection for a pancreatic mass and were diagnosed with an IPAS on final pathologic evaluation.
RESULTS: Patient age ranged from 38 to 72 with a median age of 62.5, including five males and two females. Lesions ranged from 1.4 to 7.4 cm in maximal diameter (mean 3.8 cm). All lesions were identified as round, hypervascular, well-circumscribed masses in the pancreatic tail. The most common pre-operative diagnosis was a non-functioning pancreatic neuroendocrine tumor (NF-PNET). The most common operative approach was laparoscopic distal pancreatectomy and splenectomy.
CONCLUSIONS: IPAS are benign tumors commonly mistaken for pancreatic neoplasms such as NF-PNET. A combination of CT, MRI and nuclear medicine examinations can confirm the diagnosis of IPAS and prevent unnecessary surgical resection.

A 72-year-old female presented with dyspepsia for 2 years and an incidental mass in the head of the pancreas on abdominal computed tomography (CT) scan. Patient had multiple negative endoscopic ultrasound guided biopsies. She was followed up for 3 years with serial imaging until an abdominal CT scan showed an increase in size of the pancreatic mass. Physical examination was unremarkable. Laboratory tests including tumor markers were normal. Given the enlarging size of the mass and its impingement on the portal vein, the consensus was to proceed with surgery. Histology revealed a 3.5 cm mass showing a spindle cell neoplasm with mild atypia. The lesion was well defined and nerve tissue was noted at the periphery. On immuno-stains, the spindle cells were positive for S-100 protein and negative for pan-cytokeratin, CD-34, CD-117, smooth muscle actin and Melan A, consistent with the diagnosis of a pancreatic schwannoma.

Classic polyarteritis nodosa (PAN) that targets medium-sized muscular arteries and microscopic polyangiitis (MPA), characterized by inflammation of small-caliber vessels and the presence of circulating myeloperoxidase anti-neutrophil cytoplasmic antibodies (MPO-ANCA), are distinct clinicopathological entities of systemic vasculitis. A 66-year-old woman presented with fever, cholestasis and positive MPO-ANCA. Radiological examination showed a pancreatic mass compressing the bile duct. Therefore, we performed pancreatoduodenectomy. Histopathological examination revealed that necrotizing vasculitis predominantly affecting the medium-sized vessels, spared arterioles or capillaries in the pancreas, a finding consistent with PAN. Unexpectedly, renal biopsy revealed small-caliber vasculitis and glomerulonephritis, supporting MPA. The initial manifestation of a pancreatic mass associated with vasculitis has only been reported in 7 articles. Its diagnosis is challenging because no reliable clinico-radiological findings have been observed. Clinicians should be aware of such cases and early diagnosis followed by immunosuppression is mandatory. Our findings may reflect a polyangiitis overlap syndrome coexisting between pancreatic PAN and renal MPA.