Cytological Diagnosis of Pancreatic Solid-Pseudopapillary Neoplasm: A Single-Institution Community Practice Experience

Introduction. Pancreatic solid-pseudopapillary neoplasm (SPN) is a rare tumor that typically occurs in young females. Although a cytological diagnosis may be easily made in this age group when there are typical features, atypical clinical presentations and unusual cytological features may make this a challenging diagnosis. We present our single-institution experience in a cohort of these tumors, outlining both typical and atypical features. Awareness of unusual clinical and cytological features can help to avoid pitfalls during diagnosis. Methods. We performed a review of all cases of pancreatic SPNs diagnosed over a 15-year period (January 2007 to December 2021). Detailed cytological, clinical, and follow-up histological features were presented and analyzed. Results. Twenty-two cases of SPN were diagnosed at our institution during this 15-year period. Patients ranged from 12 to 73 years of age (mean 33 y, median 26 y) and included 19 females and 3 males. Seventeen patients had cytological material, and fourteen were diagnosed by EUS-FNA. Typical cytological features included papillary clusters with central capillaries, myxoid stroma, monomorphism, cercariform cells, and hyaline globules. Atypical or unusual cytological features that were seen in a few cases were multinucleated giant cells, clear cells, and/or foamy macrophages. A few cases showed features that were similar to pancreatic neuroendocrine tumors (PanNETs). Tumor cells were always positive for β-catenin, CD10, CD56, cyclin-D1, progesterone receptor (PR), and vimentin by immunohistochemistry. They were always negative for chromogranin. Pancytokeratin and synaptophysin stains were positive in 9% and 46% of cases evaluated, respectively. All cases had histological confirmation on resection. The median follow-up duration was 69 months (a range of 2–177 months), with only three cases lost to follow-up. No recurrence or metastasis was identified. Conclusions. We present our experience with cytological diagnoses of SPN in a well-characterized cohort of 22 patients with histological correlation and follow-up data. These tumors occur over a wide range and show varied cytological features. SPNs can be confidently diagnosed on limited cytological material, with limited panel immunohistochemistry aiding diagnosis in atypical cases. Recognizing the associated degenerative changes is crucial in avoiding a misdiagnosis

Gall bladder and extrahepatic bile duct lymphomas: clinicopathological observations and biological implications

Lymphomas of the gall bladder and extrahepatic bile ducts are exceedingly rare. We present the clinicopathological features of 19 cases from our files; 14 patients had primary lymphoma (13 involving gall bladder and 1 involving common hepatic duct), while 5 had systemic lymphoma on further work-up. Most patients presented with symptoms mimicking cholecystitis. The most common primary lymphoma types were diffuse large B-cell lymphoma, extranodal marginal zone lymphoma, B-lymphoblastic lymphoma, and follicular lymphoma. Two cases had features of lymphomatous polyposis, one a case of follicular lymphoma and the second a case of mantle cell lymphoma, with disease limited to the mantle zones, so-called in situ mantle cell lymphoma. Other rare lymphoma subtypes not described earlier in this site included the extracavitary variant of primary effusion lymphoma and plasmablastic lymphoma. Patients with diffuse large B-cell lymphoma and extranodal marginal zone lymphoma were older (mean age 75.8 y) than those with other subtypes (mean age 47 y) and more likely to have gallstones (60% vs. 12.5%). A comprehensive literature review revealed 36 primary gall bladder and 16 primary extrahepatic bile duct lymphomas. When compared with primary gall bladder lymphomas, those involving the extrahepatic bile ducts present at a younger age (47 y vs. 63 y) usually with obstructive jaundice, and are less often associated with gallstones (17% vs. 50%) or regional lymph node involvement (6% vs. 31%). In conclusion, primary lymphomas of the gall bladder and extrahepatic bile ducts show a broad spectrum of disease types, but in many respects mirror the spectrum of primary lymphomas of the gastrointestinal tract

Exanetide and Pancreatic Cancer: A Case Report and Review of Relevant Literature

Introduction: Pancreatic cancer is the 4th most common cause of cancer death in the United States, and is associated with a 5 year survival rate of 5%. In recent years, epidemiological studies have raised the concern about a link between the use of antidiabetic drugs that act along the glucagon-like peptide pathway and the development of pancreatic cancer.  Additionally, pre-clinical studies have suggested that GLP-1 pathway agents may promote the malignant progression of pancreatic intraepithelial (PanIN). Exenatide, which is a glucagon-like peptide -1 agonist (GLP-1), is among the most commonly used agents in this class. Case presentation: The patient described in this case report presented with stage IV pancreatic cancer 5 years after the initiation of exanetide.  The patient and her husband raised the question of an association between exanetide and her cancer. Unfortunately, her cancer was refractory to gemcitabine based therapy, and she succumbed to her disease shortly after diagnosis.Conclusion:There is limited evidence to establish a link between this class of antidiabetic medication and pancreatic cancer. While there are preclinical studies that demonstrate a mechanism by which GLP-1 pathway drugs cause chronic pancreatitis and promotion of pancreatic oncogenesis, epidemiological studies are conflicting.  However, most of these studies had a fairly brief follow up period ( 5 years), and the process of oncogenesisis likely to be protracted over several years. This case, occurring 5 years after the initiation of the agent, highlights the need for longer epidemiological studies. As of 2007, over 700,000 patients had already used exanetide. Given the high usage of these medications and the poor prognosis associated with pancreatic cancer, any association is important. Long term clinical studies, and preclinical studies that explore the question of associated deleterious somatic mutations in this population are indicated