Three cases of retroperitoneal schwannoma diagnosed by EUS-FNA

Table 1 Patient characteristics

	Case 1	Case 2	Case 3
Age (yr), sex	22, M	40, F	46, M
Detection method	Screening	Screening	Screening
First assessment modality	US,CT	CT	US
CEA (ng/mL)	2.5	1.7	7.1
CA19-9 (U/mL)	0.0	14.0	10.0
Tumor diameter (mm)	20.0	27.4	15.0

CEA: Carcinoembryonic antigen; CA: Carbohydrate antigen; F: Female; M: Male; US: Ultrasonography; CT: Computed tomography.

Table 2 Lesion characteristics

	Case 1	Case 2	Case 3
Border	Clear	Clear	Clear
US	Hypoechoic	Hypoechoic	Hypoechoic
CT	Low density	Low density	Low density
MRI	T1 low, T2 high	T1 low, T2 high	T1 low, T2 high
Ki-67(%)	3-15	2-4	3
Follow-up duration (mo)	23	9	15

US: Ultrasonography; CT: Computed tomography; MRI: Magnetic resonance imaging.

Table 3 Reported cases of schwannoma diagnosed by endoscopic ultrasound-fine needle aspiration

Case No.	Age (yr)	Sex	Symptom	Tumor diameter (mm)	Position	US	Surgery
1[14]	79	F	Dry cough	30	SMP	Hypo	-
2[15]	59	M	None	40	Retro	Hypo	Done
3[16]	29	M	Epigastralgia	35	Retro	Hypo	Done
4[17]	37	M	None	16	Intra	Hypo	Done
5, 6, 7, 8[28]	54.51	M:F = 3:1	None	23.71	Retro	NA	-
Our case 1	22	M	None	20	Retro	Hypo	-
Our case 2	40	F	None	27.4	Retro	Hypo	-
Our case 3	46	M	None	15	Retro	Hypo	-

¹Mean. Hypo: Hypoechoic; Intra: Intrapancreatic schwannoma; NA: Not available; Retro: Retroperitoneum; SMP: Superior mediastinum posterior; F: Female; M: Male; US: Ultrasonography.