FDG PET/CT in Duodenal Follicular Dendritic Cell Sarcoma

Area of Science:

• Oncology
• Radiology
• Pathology

Background:

• Follicular dendritic cell sarcoma (FDCS) is an exceptionally rare neoplasm.
• Duodenal involvement by FDCS is exceedingly uncommon, posing diagnostic challenges.

Purpose of the Study:

• To describe the imaging characteristics of duodenal FDCS using contrast-enhanced computed tomography (CT) and fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT).

Main Methods:

• A case of duodenal FDCS was analyzed.
• Imaging findings from contrast-enhanced CT and FDG PET/CT were documented.
• Histopathologic examination with immunohistochemistry (CD21, CD35) was performed post-surgical resection.

Main Results:

• Contrast-enhanced CT showed a large, irregular duodenal mass with heterogeneous enhancement, necrosis, and calcifications.
• FDG PET/CT revealed significantly increased metabolic activity within the mass.
• Histopathology confirmed a spindle cell tumor positive for CD21 and CD35.

Conclusions:

• FDCS of the duodenum presents distinct imaging findings on CT and PET/CT.
• These imaging modalities, combined with histopathology, are crucial for diagnosing this rare entity.