Table 1. Clinical Data and Main Radiologic Findings in 18 Patients with pPNETs.

	All	Intra-abdominal	Retroperitoneal
Case	18	3	15
Age (years old)	36(range, 2–65 years)	54 (range, 3–65 years)	36(range, 2–54 years)
Sex
M	15	2	13
F	3	1	2
Location		Bladder (1); Ascending colon (1); Mesentery (1)	Adrenal gland region (5); Renal (3); Renal hilum (2); Hepatogastric gap (2); Presacral region (1); Head of the pancreas (1); Lesser curvature of stomach(1);
Size	7.2	7.1	7.2
Margin
Well-defined		1(33.3%)	8(53.3%)
Ill-defined		2(66.7%)	7(46.7%)
Necrosis		2(66.7%)	13(86.7%)
Hemorrhage		0	2(13.3%)
Cyst		1(33.3%)	7(46.7%)
Septa		0	5(33.3%)
Calcification		1(33.3%)	4(26.7%)
Enhancement
Homogenous		1(33.3%)	3(20.0%)
Heterogeneous		2(66.7%)	12(80.0%)
Tiny feeding arteries		1(33.3%)	6(40.0%)
Mild ring enhancement		0	5(33.3%)

Note: M, male; F, female.