Gastrointestinal stromal tumours of the small intestine, including duodenum (GIST)

Gastrointestinal stromal tumour more commonly occurs in the stomach. GIST is by far the most common stromal tumour in the duodenum².

Epidemiology

Age range was from 10 to 88 years, median 56 years².

Clinical features

The most common manifestation is with bleeding, usually chronic, causing anaemia, less often acute with melena². The small intestines are the most common site for GIST in association with type I neurofibromatosis, in which context they are commonly multiple².

Histopathology

The pathology resembles that at other sites. A feature not observed outside the duodenum is a haemangioma-like vascular proliferation, which is sometimes glomeruloid².

Immunohistochemistry

CD117	15/161, 109/1092, 18/183
CD34	11/161, 49/912, 7/183
vimentin	16/161, 18/183
SMA	12/161, 38/972, 14/183
CD34 and SMA	11/912
bcl-2	15/161
PGP9.5	10/161
Desmin	0/902, 0/183
S-100	19/972, 14/18 (few cells stained)3
AE1/3	0/183
CK18	5/612
CK7	0/532
CK19	0/612
EMA	0/183
GFAP	0/572
Neurofilament	2/161, 8/572
NSE	15/161
tau	12/161
synaptophysin	3/161

Expression of SMA and S-100 appears to be more common in GISTs of the small bowel than in those of the stomach, with less common expression of CD34.

Differential diagnosis

undifferentiated sarcoma - CD117 negative, these tumours are more pleomorphic

• smooth muscle tumours

• rare Schwannomas

Prognosis

Patients with recurrence, metastasis or died of disease:

Based on a series of duodenal GISTs2	<5 mitoses/50 HPF	>5 mitoses /50 HPF
< 2 cm	0/12	0
2-5 cm	4/48 (three of these deaths occurred after more than 5 years of disease)	9/18
>5 cm	12/35	18/21
Unassigned	6/6
Total	49/140 (five recurrences were more than 10 years after excision of the primary tumour)

Spread occurs within the abdominal cavity, to liver, bones or lungs, rarely ovaries, never to lymph nodes.

References

¹ Chambonniere, M. L., Mosnier-Damet, M., Mosnier, J. F. Expression of microtubule-associated protein tau by gastrointestinal stromal tumors. Human Pathol 2001;32:1166-1173.

² Miettinen, M., J. Kopczynski, et al. (2003). "Gastrointestinal stromal tumors, intramural leiomyomas, and leiomyosarcomas in the duodenum: a clinicopathologic, immunohistochemical, and molecular genetic study of 167 cases." Am J Surg Pathol 27(5): 625-41.

³ Hasegawa, T., Y. Matsuno, et al. (2002). "Gastrointestinal stromal tumor: consistent CD117 immunostaining for diagnosis, and prognostic classification based on tumor size and MIB-1 grade." Hum Pathol 33(6): 669-76.

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This page last revised 28.1.2006.

©SMUHT/PW Bishop