Fig. 2

Capsulated growth pattern in a 50-year-old male patient with metastatic rectal cancer. MR axial fast spin echo T2-weighted image (a) shows a 52 mm lesion in segment VIII of the liver surrounded by a hypointense rim (white arrows). On contrast-enhanced fat suppressed gradient recall echo T1-weighted images at delayed 3-minute phase (b), the lesion shows a target appearance with a necrotic non-enhanced central area surrounded by the enhancing capsule (white arrow). Note the enhancing fibrous septa in the viable portion of the peripheral tumor (black arrow). Gross pathology (c) confirmed the presence of a fibrous capsule (white arrows), surrounding the lesion. Note the central necrosis (black star), the tumoral glands located at the periphery (white stars) and the small fibrous septa across the periphery of the tumor (black arrow). Histological analysis (d) confirmed the presence of a peripheral fibrous capsule (Cp) clearly separating the tumor glands (T) from the liver (Li). Note the central necrosis (N)