Unique intense uptake demonstrated by (18)F-FDG positron emission tomography/computed tomography in primary pancreatic lymphoma: A case report

Abstract

Patients with primary pancreatic lymphoma (PPL), which is rare, require a different therapeutic approach and have a better prognosis than those with pancreatic cancer. However, conventional imaging modalities alone are not able to differentiate between pancreatic cancer and other rare tumors such as PPL, although the accurate diagnosis of PPL is crucial. The development of new modalities such as F-18 2'-deoxy-2fluoro-D-glucose (FDG) positron emission tomography combined with computed tomography (PET/CT) contributes to the evaluation of lymphoma staging. However, few reports are currently available regarding PET/CT findings in PPL. In this study, a 56-year old man with PPL was examined using FDG PET/CT imaging, which showed the unique intense uptake of FDG in the pancreas with atypical findings of malignancy in the CT scan and magnetic resonance images.

Figure 1

An MRI showed a mass with (A) homogeneously high signal intensity on T2-weighted images and (B) low signal intensity on T1-weighted images with gadolinium enhancement (C, 30sec; D, 60 sec and E, 180 sec).

Figure 2

(A) Early PET/CT imaging showed intense abnormal FDG uptake (SUVmax, 8.67) in the head and body of the pancreas (red arrow), and a moderately increased uptake in the tail of the pancreas (yellow arrow). (B–D) A delayed scan demonstrated a more intense FDG uptake (SUVmax, 10.3) in the pancreas.

Figure 3

(A) Microscopic examination showed diffuse infiltrative growth of T-lymphoid cells. (B and C) Immunohistochemical analysis showed that the neoplastic cells were positive for CD79a (B) and BCL-2 (C). Original magnification, ×100.