Objective: To describe sonographic features of small(less than 5.0cm) solid pancreatic pseudopapillary tumors(SPPT) in regular check-up healthy population and to show potential value of contrast-enhanced ultrasound.
Methods: Regular check-up sonographic database from 2000 to 2007 was reviewed , and six patients with a surgical pathology-proven SPPT were retrospectively studied for evaluation of sonographic appearances and features. There were 1 male and 5 females with ages from 23 to 35 years. These tumors were detected incidentally by regular check-up sonographic examination, all patients without symptoms except one patient with complaint of discomfort on the left side of the back. Contrast-enhanced sonographic examination was conducted in one patient prior to surgery.
Results: Gray scale sonographic imaging features included solid homogenous hypoechoic mass in 2 cases, one of which had a hyperechoic rim, complete cystic echofree mass in 1 case, mixed solid and cystic mass in 2 cases, one of which with central hyperechoic area and one case the lesion just showed a superficial curved hyperechoic rim with posterior shadow. The size of the lesions ranged from 2.5 cm to 5.0 cm in diameter with a mean diameter of 4.2 cm. In one solid appearance tumor with contrast-enhanced imaging, the typical peripheral capsule enhancement and intra-tumor unenhanced area were evidenced in arterial phase.
Conclusions: Regular check-up healthy sonographic examination can find relatively small size SPPT and allow diagnosis based on typical imaging features. Contrast-enhanced ultrasound shows greater detail of the tumor capsule and heterogeneous enhancement pattern, which are helpful for diagnosis and differentiation.