Primary Pancreatic lymphoma: a rare clinical entity

Abstract

Primary pancreatic lymphoma is a rare clinical entity representing <0.5% of pancreatic cancers and 1% of extranodal lymphomas. Due to the paucity of cases described in the literature, its clinicopathological features, differential diagnosis, optimal therapy and outcomes are not well defined. As the clinical manifestations are often non-specific, it can create a diagnostic pitfall for the unwary physician. Preoperative distinction of adenocarcinoma and primary pancreatic lymphoma is critical since the management and prognosis of these malignancies are mutually exclusive. Due to its rarity, epidemiological studies have been difficult to conduct. Chemotherapy with R-CHOP (rituximab, cyclophosphamide, doxorubicin and vincristine) has proven to be effective. The authors present the case of a 52-year-old man with epigastric pain and obstructive jaundice. Further investigation with a CT of the abdomen and pelvis showed a low attenuation mass in the head of the pancreas measuring 35×25 mm, suspicious for malignancy. The mass involved the common bile duct distally causing moderate retrograde intrahepatic and extrahepatic biliary tree dilation of 14 mm. He underwent endoscopic retrograde cholangiopancreatography, sphincterotomy and insertion of a stent. Core biopsies confirmed the diagnosis of a high-grade B cell pancreas lymphoma. He started treatment with R-CHOP and prednisolone. Due to disease progression, he started treatment with DA-EPOCH-R (etoposide phosphate, prednisone, vincristine sulfate, cyclophosphamide, doxorubicin hydrochloride and rituximab). There was no clinical response, and treatment with RICE (rituximab, ifosfamide, carboplatin and etoposide) was initiated. He showed partial response and was under consideration for chimeric antigen receptor T cell therapy. He deteriorated clinically and succumbed to his disease 5 months following his initial presentation. This paper will provide an overview of the spectrum of haematological malignancies and describe useful features in distinguishing primary lymphoma of the pancreas from an adenocarcinoma, hence avoiding its surgical resection.

Keywords: Emergency medicine; General surgery.

Figure 1

CT of the abdomen and pelvis with intravenous contrast showed a low attenuation mass in the head of the pancreas measuring 35×25 mm, suspicious for malignancy.

Figure 2

Large lymphoid cells with frequent mitotic figures and apoptotic bodies. High power, ×40.

Figure 3

CD20 immunostain showing B cells. High power, ×20.

Figure 4

The Ki67 proliferation index was very high at 90%.

Figure 5

CD10 immunostain showed a diffuse large B cell lymphoma, of germinal centre B cell subtype.

Figure 6

Further investigation with contrast-enhanced CT of the abdomen and pelvis in the portal venous phase showed rapid progression of the primary and metastatic disease with an enlarged mass in the central abdomen in relation to the enlarged pancreatic head tumour.