Very rarely lymphoma primarily or secondarily involves the pancreas. Involvement of the pancreatic parenchyma with lymphoma clinically may mimic pancreatic ductal adenocarcinoma (PDA) and other mass‐forming pancreatic lesions. Endoscopic ultrasound fine needle aspiration (EUS‐FNA) is the first step in the diagnostic pathway of managing these patients by providing a cytology specimen. Cytologically, lymphoma of pancreas can be misdiagnosed for a wide variety of pancreatic neoplastic and non‐neoplastic lesions. Cytological differential diagnosis includes well‐differentiated adenocarcinoma, acinar cell carcinoma, well differentiated neuroendocrine tumor, and autoimmune pancreatitis. Gastroenterologist's skills in providing adequate sample for preparing smears, cell blocks and/or performing flow cytometry, and also cytopathologist's skills in detecting atypical lymphocytic population are crucial factors. Although cytology examination has limitations to subclassify lymphoma, it plays a key role to redirect clinicians into the right patient‐care pathway. In this article, we present two cases of pancreatic lymphoma with emphasis on the discriminating cytomorphological features, and we also review literatures with reports of primary pancreatic lymphoma (PPL) to better understand the characteristics of this rare lesion.

Introduction/Objective Primary cutaneous follicle center lymphoma (PCFCL) is the most common primary cutaneous B-cell lymphoma. It arises from mature germinal center B lymphocytes. Here we report two cases of PCFCL with parotid gland involvement. Methods First case is a 66-year-old male with an enlarging forehead mass for nine months and a painless nodule on the right pre-auricular skin. Second is a 39-year-old male with a history of a recurring scalp spindle cell B-cell lymphoma now presenting with an enlarging lesion on the scalp and “fullness” in the right neck. There was no nodal or other extranodal involvement found in either case. Skin and parotid gland biopsies were obtained in both cases. Results Case one: The skin and parotid gland demonstrated sheets of predominantly medium sized infiltrating lymphoma cells, positive for CD20, Bcl-6, CD5 (dim) and Bcl-2 (dim), and negative for CD10, Bcl-1, and MUM-1. The epidermis was spared. Case two demonstrated medium sized, spindle shaped lymphoma cells. The skin showed a vague follicular growth pattern, sparing the epidermis. The parotid gland showed diffuse infiltration by lymphoma cells, positive for CD20 and Bcl-6, Bcl-2 (dim) and no definite positivity for CD10. Fluorescent in situ hybridization for t(14;18) translocation was absent in both cases. Conclusion Dissemination of PCFCL to extracutaneous sites is uncommon (~10% of cases) and to our knowledge, has not been reported in the parotid gland. Here we present two unique cases, which in the absence of nodal disease, prove the diagnosis of PCFCL with parotid gland involvement.

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