Primary pancreatic lymphoma is a rare form of extranodal lymphoma comprising less than 0.5% of pancreatic tumours originating from the pancreatic parenchyma.1 Although rare, this particular neoplasm is amenable to treatment even in very advanced stages. The clinical and radiological findings are not pathognomonic and the diagnosis is established only after histopathologic examination.2 Abdominal pain is the commonest presenting feature (83%), followed by a palpable abdominal mass (58%) and weight loss (50%).3 In our case the presenting symptom was repeated episodes of unconciousness probably due to low blood glucose levels caused by destruction of the pancreatic tissue by the tumour infiltration.

Our patient was a forty year old male who presented with fever of eight days duration and complaint of episodes of unconsciousness off and on. At the time of admission the patient was drowsy and investigations revealed random blood sugar levels of 40 mg%. The patient did not respond to intravenous glucose therapy and expired within four hours of hospital stay. An autopsy was performed.

The salient feature noted at autopsy was the presence of a large ill-defined intra-abdominal mass measuring 8 cm x 6 cm x 5 cm. The cut section was fleshy and only in a small area could normal appearing pancreatic tissue be appreciated (Fig. 1). There was no tumour involvement at any other site and neither was there any evidence of localized or generalized lymphadenopathy.

Multiple sections from the tumour mass were studied. Most of the sections showed a monotonous population of small round cells in sheets separated by sparse fibrous septae (Fig. 2). The cells had infiltrated the pancreatic parenchyma and only isolated foci of viable pancreatic acini were seen. The cells had scanty cytoplasm, the nuclear chromatin was coarse and prominent nucleoli were seen at few sites. Mitotic figures were scarce. On the basis of light microscopy the impression given was a low grade non-Hodgkin’s lymphoma of the pancreas.

Immunohistochemistry was done for confirming the diagnosis. Positivity for pan B cell markers was noted. On the basis of immunohistochemistry the tumour was typed as a primary low grade B cell lymphoma of the pancreas

Fig. 1 : Large fleshy white tumour mass replacing the entire pancreas. There is no evidence of any tumour involvement in any of the adjoining organs or regional lymph nodes.	Fig. 2 : H and E stained section showing small round cells in loose sheets separated by sparse fibrous septae (400 X).

Primary neoplasms of the pancreas are most often adenocarcinomas. Non-Hodgkin’s lymphomas involving the pancreas are less common but well documented. Primary pancreatic lymphoma is an extremely rare neoplasm that may be confused with pancreatic adenocarcinoma.4 It is important to differentiate between treatment and prognosis of the two conditions. The age at presentation ranges from 37 to 74 years (our patient was 40 year old) and abdominal pain is the commonest presenting feature.5 However there are case reports where there is a mention of a clinical presentation in the form of a diabetic crisis. Since most of the case reports in literature mention a favourable outcome following treatment it is important to establish a definitive diagnosis for this disease, to remove the tumour and to treat the patient with appropriate chemotherapy.2,6