Diagnostic significance of gently sloping depression and irregular margin in superficial elevated colorectal tumors.
BACKGROUND
Recently, superficial elevated colorectal tumors have been increasingly diagnosed after improvements in endoscopic instruments and techniques. However, their biological characteristics remain obscure and it is difficult to predict malignant potential. The aim of this study is to clarify the characteristics of superficial elevated tumors in endoscopic examination for the evaluation of malignant potential.


METHODS
Sixty-three resected superficial elevated colorectal tumors more than 10 mm in diameter were analyzed with regard to their morphological characteristics and histological findings. The samples were classified according to the presence of a gently sloping depression and irregular margin at the edge. Their depth of vertical invasion and the degree of depression were examined.


RESULTS
The rate of carcinoma in 27 lesions with a gently sloping depression was significantly higher than in 36 lesions with an even surface. The rate of carcinoma in 46 lesions with irregular margin was significantly higher than in 17 lesions without irregular margin. A multivariate analysis revealed that the coexistence of both IM and GSD was significantly associated with submucosal invasion. Statistical associations of age, tumor location, gender, and pathological grade with submucosal invasion were not observed.


CONCLUSIONS
In superficial elevated colorectal tumors, a gently sloping depression and irregular margin at the edge when viewed endoscopically may be a predictor of malignant potential. These characteristics should be given priority when deciding on treatment.
Nakahara
Takako
T
Division of Diabetes, Digestive, and Kidney Diseases, Department of Clinical Molecular Medicine, Kobe University Graduate School of Medicine, Kobe, Japan.
Aoyama
Nobuo
N
Maekawa
Shuji
S
Tamura
Takao
T
Shirasaka
Daisuke
D
Kuroda
Kohei
K
Nishioka
Chiharu
C
Morita
Yoshinori
Y
Kasuga
Masato
M