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First report of primary pancreatic natural killer/T-cell nasal type lymphoma.

BACKGROUND
Primary pancreatic lymphoma (PPL) is an extremely rare form of extranodal malignant lymphoma and pancreatic tumour. Natural killer/T-cell lymphoma is an aggressive rare form extranodal lymphoma with a predilection for the nasal cavity/nasopharynx, it can arise in other organs such as skin, testicles, spleen, adrenal, or GI tract, but the initial presentation of our patient in the pancreas is unreported.


CASE PRESENTATION
We present a case of primary pancreatic natural killer/T-cell nasal type lymphoma in a 62-year-old man. The presenting symptoms were non-specific only for upper abdominal pain and weight loss. Imaging techniques showed the lesion was located in the head of pancreas. Computed tomography (CT) scanning and otorhinolaryngology examination were negative for nasopharyngeal lymphoma. The initial concern was for pancreatic tumor and the patient underwent pancreaticoduodenectomy. The diagnosis of primary pancreatic natural killer/T-cell nasal type lymphoma was established as the combination of NK-lineage antigens (TIA-1, granzyme B, CD56) with EBV-expression.


CONCLUSIONS
This is the first case of primary pancreatic natural killer (NK)/T-cell nasal type lymphoma. PPL, although a rare pathologic entity, should be considered in the differential diagnosis for a large homogeneous mass with extrapancreatic extension in the head especially in those of normal serum CA 19-9 level.