Purpose: To present the imaging findings of serous cystadenoma (SCA) and discuss the main problems of differential diagnosis with other cystic pancreatic lesions.
Materials and methods: 55 cases of SCA were reviewed; all the lesions proved to be benign at pathology. 35 tumors were evaluated with Ultrasonography (US), 49 with Computed Tomography (CT), and 15 with Magnetic Resonance Imaging (MRI).
Results: Among the patients who underwent either demolitive (47) or derivative (3) interventions, two different morpho-structural patterns were identified: microcystic (37), and oligocystic (13). The diagnosis of SCA, possible in the presence of microcystic pattern, was achieved in 63% of cases by US (22/35), in 63% of cases by CT (31/49), and in 73% of cases by MRI (11/15). In 12 patients evaluated with all the imaging modalities, the combined information allowed a correct diagnosis in 10 cases (83%). The 13 oligocystic tumors were almost always undistinguishable from other cystic masses of the pancreas.
Conclusions: The diagnosis of SCA can be considered certain if a microcystic pattern is detected. A correct diagnosis is not achievable in the presence of oligocystic architecture. MRI is the best imaging modality in characterizing this tumor.