Pancreatic sarcomatoid carcinoma: CT, MRI, and 18F-FDG PET/CT features

Abstract

Aim: To investigate computed tomography (CT), magnetic resonance imaging (MRI), and combined 2-[¹⁸F]-fluoro-2-deoxy-d-glucose (¹⁸F-FDG) positron-emission tomography (PET)/CT features of pancreatic sarcomatoid carcinoma (PSC).

Materials and methods: The hospital database was searched retrospectively for the patients with PSC confirmed at histopathology after surgery. Ten patients who underwent unenhanced and enhanced CT (n=4), unenhanced and enhanced MRI (n=2), ¹⁸F-FDG PET/CT (n=2), and both enhanced CT and ¹⁸F-FDG PET/CT (n=2) were enrolled. Two patients underwent additional delayed PET/CT. The maximum standardised uptake value (SUVmax) was measured on PET/CT images.

Results: Eleven lesions were detected in 10 patients. Solid and cystic components (n=6), intratumoural haemorrhage (n=1), nodular calcification (n=2), main pancreatic duct dilatation resulted from lesion obstruction (n=5) or compression (n=3), cholangiectasis (n=5), vascular and peripheral organ invasion (n=5 and 6, respectively), hepatic and lymphatic metastases (n=4 and 2, respectively) were detected. All five lesions in four patients who underwent PET/CT showed intense FDG uptake on PET/CT with SUVmax (16, range 10.9-21.1). Increase of FDG uptake (SUVmax = 18.9, 20.1, and 27.3, respectively) was revealed on the delayed scan of three lesions in two patients.

Conclusions: PSCs were more commonly ill-defined solid cystic masses, which caused pancreatic duct obstruction/compression without pancreatic parenchymal atrophy, and these masses on PET/CT showed high FDG uptake on both initial and delayed PET/CT.