Tumor growth rate of pancreatic serous cystadenomas: Endosonographic follow-up with volume measurement to predict cyst enlargement

Background

Serous cystadenomas are benign lesions of the pancreas. Usually they are diagnosed incidentally on cross-sectional imaging studies. Endosonography is a valuable tool in the diagnosis and follow-up of these cystic lesions. Given its benign nature, surgical resection is advised only in symptomatic patients. The interval and length of surveillance is not well established.

Methods

A retrospective single center study was done. All the patients with a pancreatic serous cystadenoma sent for an endosonographic evaluation, between December 2008 and December 2015 were included. The lesions were follow-up endosonographically at least once, in a 12 months interval. Volume was measured with the formula π/6 × (d1 x d1 x d2). Two groups were evaluated: patients with a volume under 10?mL (Group 1) and those with a volume of 10?mL or more at presentation (Group 2). Growth rate between these two groups was compared.

Results

Thirty-one patients were analyzed, with a mean age of 58.2 years. Patients were mainly women (87%). Twenty-four patients in Group 1 had a mean enlargement of 0.67?ml per year, whereas patients in Group 2 had a mean enlargement of 9.8?ml per year. The growth rate difference between these two groups was statistically significant (p?=?0.0001).

Conclusion

Asymptomatic patients with pancreatic serous cystadenomas should be follow-up for enlargement. Small volume lesions have a low risk of enlargement compared with high volume and macrocystic serous cystadenomas. Volume at presentation is a feature to analyze when defining surveillance interval.