Data of 83 patients met the criteria for including in the study.
The study included 53 males (64%) and 30 females (36%).
Median age at presentation was 56 years.
The most common tumors were GISTs (36.1%),
followed by lymphomas (26.5%),
adenocarcinomas (24.1%),
and others (13.3%; including 4 inflammatory fibroid polyps,
2 leiomyomas,
1 adenoma,
1 schwannoma,
1 leiomyosarcoma,
1 NET and 1 cavernous hemangioma).
The anatomical distribution of the small bowel tumor was 21 duodenum,
18 jejunum,
44 ileum.
About half of adenocarcinomas (11/20) were located in the duodenum,
in contrast to most lymphomas (21/22) were located in the jejunum and ileum.
GISTs occurred in all parts of small bowel.
Consequently,
anatomical location cannot help to rule out any tumor in clinical practice.
Therefore,
location is not a potential finding in differentiating among small bowel neoplasm (Table 1).
The pattern of growth was classified according to prominent growth as extramural growth,
bowel wall thickening and polypoid lesion (Figure 1).
The extramural growth pattern is reliable prediction of GISTs,
with PPV of 82.3%.
None of adenocarcinoma and lymphoma presented this pattern.
Bowel wall thickening was the common pattern of adenocarcinomas and lymphomas.
Apple-core-like (figure 2),
shoulder defect (figure 3) and focal involvement being less than or equal to 5 centimeter were probably findings of adenocarcinomas,
with PPV of 81.8%,
71.4% and 76.9%,
respectively.
While on the contrary,
aneurysmal dilatation of the lumen (figure 4) and marked thickening of wall bowel equal or greater than 25 mm could strongly suggest lymphoma,
with PPV of 87.5% and 72.7%,
respectively.
(Table 2,
3)
All of GISTs showed moderate to avid enhancement [12].
Tumor density of greater than 110 HU on venous phase was likely to be GISTs,
with PPV of 84.9%.
Proliferation of blood vessels on tumor surfaces (figure 5) could help discriminate GISTs from the others,
with PPV of 92%.
Enhancement of adenocarcinoma and lymphoma were variable.
But,
they seldom enhanced more than 110 HU and not presented the proliferation of blood vessels on tumor surfaces.
(Table 4,
5,
6)
Enlarged lymph node with shorter axis greater than 20mm or multiple lymph nodes fused together forming a bulky mass were likely to be lymphoma,
with specificity of 100%.
(Table 7)
|
Adeno-carcinoma
|
Lymphoma
|
GIST
|
Others
|
Total
|
Deodenum
|
11
|
1
|
8
|
1
|
21
|
Jejunum
|
2
|
2
|
11
|
3
|
18
|
Ileum
|
7
|
19
|
11
|
7
|
44
|
Total
|
20
|
22
|
30
|
11
|
83
|
Table 1: Distribution of small bowel tumors by pathology and anatomical distribution.
|
Adeno-carcinoma
|
Lymphoma
|
GIST
|
Others
|
Total
|
Polypoid lesion
|
2
|
4
|
2
|
5
|
13
|
Extramural growth
|
0
|
0
|
28
|
5
|
33
|
Bowel wall thickening
|
18
|
18
|
0
|
1
|
37
|
Total
|
20
|
22
|
30
|
11
|
83
|
Table 2: The pattern of growth of small bowel tumors.
|
Adeno-carcinoma
|
Lymphoma
|
GIST
|
Others
|
Total
|
Shoulder defect
|
10
|
4
|
0
|
1
|
15
|
Apple-core-like
|
9
|
2
|
0
|
0
|
11
|
Aneurysmal dilatation
|
2
|
14
|
0
|
0
|
16
|
Focal involvement
|
10
|
2
|
0
|
1
|
13
|
Marked thickening
|
3
|
8
|
0
|
0
|
11
|
Table 3: Specific patterns of bowel wall thickening.
|
Adeno-carcinoma
|
Lymphoma
|
GIST
|
Others
|
Total
|
Moderate to avid
|
16
|
14
|
30
|
5
|
65
|
Mild
|
4
|
8
|
0
|
6
|
18
|
Total
|
20
|
22
|
30
|
11
|
83
|
Table 4: Enhancement feature in small bowel tumors.
|
GISTs
|
Non GISTs
|
Total
|
> 110 HU
|
13
|
8
|
21
|
≤ 110 HU
|
17
|
45
|
62
|
Total
|
30
|
53
|
83
|
Table 5: Enhancement threshold 110HU on venous phase
|
Adeno-carcinoma
|
Lymphoma
|
GIST
|
Others
|
Total
|
BVoTS (+)
|
0
|
0
|
23
|
2
|
25
|
BVoTS (-)
|
20
|
22
|
7
|
9
|
58
|
Total
|
20
|
22
|
30
|
11
|
83
|
Table 6: Proliferation of blood vessels on tumor surfaces (BVoTS).
|
Adeno-carcinoma
|
Lymphoma
|
GIST
|
Others
|
Total
|
Enlarged lymph nodes
|
12
|
20
|
0
|
0
|
32
|
Shorter axis >20mm
|
0
|
7
|
0
|
0
|
7
|
Multiple lymph nodes fused together
|
0
|
10
|
0
|
0
|
10
|
Table 7: Lymph nodes in small bowel tumors.