Adeel Rahim Seyal MD, Presenter: Grant, Siemens AG

Keyur Parekh MD, Abstract Co-Author: Grant, Siemens AG

Vahid Yaghmai MD, Abstract Co-Author: Nothing to Disclose

To determine growth rate of biliary cystadenoma to estimate suitable follow-up imaging interval.

The HIPAA compliant retrospective study was IRB approved. Patients with histopathologically proven primary or recurrent biliary cystadenoma with at least two cross-sectional imaging studies (CT and/or MR scans) performed were included. Comparison was done with simple liver cysts. Volume of biliary cystadenomas and liver cysts was calculated and growth kinetic parameters were analyzed using doubling time (DT) and reciprocal of doubling time (RDT) where DT=(T2 -T1)xlog2/(logV2-logV1) and RDT=1/DT. Positive RDT indicates growth while negative RDT indicates regression.

Eleven pathologically proven biliary cystadenoma were evaluated in 9 adult patients (all females). Eleven hepatic cysts in another 9 adult patients were also evaluated. Median [interquartile range (IQR)] baseline volume for cystadenoma and liver cysts was 20.1 ml (8.7, 190.3) and 2.1 ml (1.0, 3.3) respectively. Mean interscan interval for cystadenoma and liver cysts was 319.9 days (range 25 – 787) and 543 days (range 13 – 1812) respectively. All cystadenomas (100%) showed increase in size with mean RDT of 0.87 ± 0.7. Median (IQR) DT was 581.5 days (319.2, 1661). Liver cysts had mean RDT of 0.45 ± 1.1 and median (IQR) DT of 4223 days (1425, 16152). RDT was significantly different between two groups (P = 0.0081).

Slow growth of biliary cystadenomas suggests that short frequency follow-up imaging of less than one year to monitor change in size of these lesions may not be indicated.

Biliary cystadenomas grow very slowly and may be followed on imaging.

Seyal, A, Parekh, K, Yaghmai, V, Growth Rate of Biliary Cystadenomas: Value of Short Term Follow-up Imaging.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14012189.html