| Theme |
Villous Tumor |
| Title |
Differential diagnosis between villous tumors and nodular aggregating lesions of the colon and rectum: where do you draw the line? |
| Author |
Jun Horiguchi |
Division of Endoscopy, Diagnostic Imaging Tochigi Cancer Center |
| Author |
Hironobu Umezawa |
Division of Endoscopy, Diagnostic Imaging Tochigi Cancer Center |
| Author |
Hironobu Ohyanagi |
Division of Endoscopy, Diagnostic Imaging Tochigi Cancer Center |
| Author |
Yasuhiko Saitou |
Division of Endoscopy, Diagnostic Imaging Tochigi Cancer Center |
| Author |
Yoshitaka Hirahara |
Division of Endoscopy, Diagnostic Imaging Tochigi Cancer Center |
| Author |
Tsutomu Ishikawa |
Division of Endoscopy, Diagnostic Imaging Tochigi Cancer Center |
| [ Summary ] |
We investigated endoscopic differentiation of villous tumors of the colon from noduleaggregating lesions of the colon. Macroscopic findings were classified as: AN, flat sessile elevated lesion composed of multiple aggregated nodules; or VT, lesions resembling AN, but with a surface covered with villi. Clinicopathologically, we found that pure villous tumors were rare, and tubular and villous components coexisted in various ratios. Therefore, lesions were classified in relation to the ratio of villous components, and a comparison was made with the macroscopic findings. Lesions having villous components were more common among the elderly, and often had cancerous foci in someareas. To confirm lesions with villous components endoscopically, it was necessary to identify their unique villous structure by making observing them at close range. However, lesions with villous components consisted of both villous and tubular components, with varying degrees of atypia. Furthermore, in some lesions with villous components, histological types differed between surface and deep layers or between the base and apex of an elevated area, farther complicating the differential diagnosis between villous tumors and nodule-aggregating lesions. Hence, when identifying the location of villous components endoscopically, it will be important to perform dye-spraying magnifying colonoscopy and to carry out an accurate his tological biopsy. |