PALZ Case 1

Patient with a high differentiated neuroendocrine metastatic tumor. PET study after i.v. application of Ga-68-DOTATOC,
a tracer which binds to the somatostatin receptor 2 (SSTR 2).


1. This is a fused image of parametric images based on the regression model. Intercept images (black and white scale) demonstrate the perfusion-dependent part of the tracer and show the heart and the vessels very well. Slope images (color scale) demonstrate the internalized part of the peptide. This is a transversal image at the level of the heart demonstrating multiple DOTATOC positive metastatic lesions in the dorsolateral, dorsomedial and ventromedial part of the caudal thoracic wall as well as in the dorsal mediastinum.		2. Same patient, fused slope and intercept images at the level of the cranial third of the liver. The images demonstrate a high internalization of DOTATOC in a liver metastasis in the ventrolateral part of the right liver lobe and in the right paraaortic area. Both lesions are metastatic (liver metastasis and lymph node metastasis).

3. MIP image of the thorax of the same patient demonstrating multiple SSTR-positive lesions in the mediastinum and in the right thoracic wall.

1. Two-tissue compartment model for one thoracic metastasis after application of Ga-68-DOTATOC. The time activity curve demostrates a slow increase of the tracer up to 60 min p.i.. The rate constants for the receptor binding (k1) and internalization (k3) are moderately increased. The fractional blood volume VB is slightly enhanced.

2. The fractal dimension of the DOTATOC time activity curve is high. This is indicative for a more chaotic tracer distribution.