[Primary pancreatic lymphoma. A rare cause of pain-free icterus]

A 54-year-old man was admitted because of increasing pain-free jaundice during the preceding two weeks. There was no resistance on palpation of the abdomen. The liver was palpable and of normal consistency, two finger-breadths below the right costal margin. Neither spleen nor lymph nodes were palpable.

Total bilirubin was 7.9 mg/dl, alkaline phosphatase 467 U/l, gamma-GT 850 U/l. WBC and differential counts were normal. The tumour marker CA 19-9 was raised to 117 U/l. Ultrasonography revealed dilatation of the intra- and extrahepatic bile ducts and a 3 cm echo-poor tumour in the head of the pancreas. Colour Doppler sonography showed both portal and splenic veins to be patent. Endoscopic retrograde cholangiopancreatography demonstrated a mild stenosis of the main pancreatic duct at the transition between the head and body of the pancreas, and a filiform stenosis of the choledochal duct. CT showed an nonhomogeneous head of the pancreas. As the suspected malignant tumour of the head of the pancreas seemed resectable no preoperative fine-needle biopsy was performed.

Whipple's operation (partial duodenopancreatectomy) was performed, but a small tumour infiltration in the portal vein had to be left. The resected specimen surprisingly showed a 2.5 cm centroblastic-centrocytic lymphoma which had infiltrated the head of the pancreas. Postoperative imaging showed para-aortic lymph nodes in the abdomen, maximally 1 cm in diameter. Subsequent radiotherapy was without complication.

Primary pancreatic non-Hodgkin lymphoma is a rare lesion with special therapeutic consequences. The difficult differential diagnosis from pancreatic carcinoma is usually possible only, in operable cases, from the resected specimen. Every inoperable pancreatic tumour should be biopsied in case it is a malignant lymphoma.