Wieland H. Sommer MD, Presenter: Nothing to Disclose

Christoph Johannes Zech MD, Abstract Co-Author: Nothing to Disclose

Andreas Helck MD, Abstract Co-Author: Nothing to Disclose

Christoph Auernhammer MD, PhD, Abstract Co-Author: Nothing to Disclose

Maximilian F. Reiser MD, Abstract Co-Author: Nothing to Disclose

Karin Anna Herrmann MD, Abstract Co-Author: Nothing to Disclose

To analyze and compare MR-morphologic characteristics in liver metastases derived from neuro-endocrine tumors (NET) with liver metastases derived from other primary tumors.

Between 2004 and 2008, 54 patients patients (m/f =36/18) with proven hepatic metastases of NET underwent MRI of the liver using a 1.5T MR-scanner (Magnetom Avanto, Germany). The standard imaging protocol included pre-contrast T2w SSFSE, T2w TSE, T1w 2D and 3D-GRE imaging followed by contrast enhanced imaging with liver-specific contrast agents. A total of 117 MRI examinations were performed and analyzed by 2 board certified radiologists specified in liver imaging. The signal intensity (SI) characteristics of the liver lesions in T2w and T1w imaging (4-point-scale), presence of central necrosis and fluid-fluid-levels (FFL), otherwise rare in hepatic metastasis, were evaluated in consensus. This was compared to a control group, consisting of 54 patients with primary tumors of other origin, these patients underwent 60 MRI examinations.

SI in T1w imaging did not differ between both groups, however, in T2w imaging, liver metastases of GEP-NET were significantly more often hyperdense or strongly hyperdense than metastases of other origins (p<0.05). Central necrosis showed a similar frequency in both groups (GEP-NET: 54/117; Control: 29/60). However, FFL were only observed in the GEP-NET group: 12 of 54 patients with metastases of GEP-NET showed FFL, while none of the control group showed FFL (p<0.05).

Hepatic metastases from GEP-NET are characterized by high or very high SI in T2w pre-contrast imaging. The occurrence of FFL may be considered a characteristic morphologic sign of this entity.

Liver metastases of NET show characteristic imaging features, different from other metastases; these are especially fluid-fluid-levels and higher SI in T2w precontrast imaging.

Sommer, W, Zech, C, Helck, A, Auernhammer, C, Reiser, M, Herrmann, K, Fluid-fluid Levels: A Characteristic Sign in Liver Metastases of Gastro-Entero-Pancreatic Neuroendocrine Tumors.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8016144.html