Tomographic findings of gastric gastrointestinal stromal tumor and correlation with the mitotic index.
BACKGROUND
Gastrointestinal stromal tumors are uncommon abdominal neoplasms and can affect any portion of the gastrointestinal tract.


OBJECTIVE
Describe the tomographic findings of the gastrointestinal stromal tumor of gastric origin, correlating it with the mitotic index.


METHODS
Twenty-one patients were selected within the period of January 2000 and 2008, with histopathological and immunohistochemical diagnosis of gastric gastrointestinal stromal tumors, who presented computed tomography done before the treatment. The tomographic variables analyzed were lesion topography, dimensions, contours, morphology, pattern and intensity enhancement through venous contrast, growth pattern, invasion of adjacent organs, presence of ulceration, fistula, calcifications, infiltration of mesenteric fat, lymphadenopathy and metastasis. The mitotic index was determined through optic microscopy, counting the number of mitosis figures in 50 high power fields.


RESULTS
The tumors were located in the body (66.7%) or gastric fundus (33.3%), with dimensions varying between 4.2 and 21.2 cm (average of 10.5 cm). The growth was predominantly extraluminal (47.6%) or intra/extra luminal (28.6%). The enhancement by venous contrast was heterogeneous in 66.7%. The statistical analysis showed that irregular morphology (P = 0.027) and infiltration of mesenteric fat (P = 0.012) presented correlation with the high mitotic index.


CONCLUSIONS
In the present study, most part of the tumors were located in the gastric body, with average size of 10.5 cm, presenting central hypo dense area, heterogeneous enhancement through contrast and predominantly extra luminal growth. Irregular morphology and infiltration of mesenteric fat present statistical correlation with high mitotic level.
Colégio Brasileiro de Radiologia (CBR), São PauloSP, Brasil.
Gustavo Lemos
GL
Pelandré
Departamento de Radiologia da, Universidade Federal do Rio de Janeiro (UFRJ), RJ, Brasil.
Maria Célia
MC
Djahjah
Departamento de Radiologia da, Universidade Federal do Rio de Janeiro (UFRJ), RJ, Brasil.
Emerson Leandro
EL
Gasparetto
Departamento de Radiologia, Universidade Federal Fluminense (UFF), NiteróiRJ, Brasil.
Marcelo Souto
MS
Nacif
Departamento de Radiologia da, Universidade Federal do Rio de Janeiro (UFRJ), RJ, Brasil.
Edson
E
Marchiori
Departamento de Cirurgia Oncológica, Instituto Nacional de Câncer (INCA), Rio deJaneiroRJ, Brasil.
Eduardo Linhares Riello de
EL
Mello
D000368:Aged; D005260:Female; D046152:Gastrointestinal Stromal Tumors / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D008940:Mitotic Index; D011237:Predictive Value of Tests; D013274:Stomach Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D014057:Tomography, X-Ray Computed