| Theme | True type IIc colorectal lesion? -- An issue of its morphological diagnosis | |
|---|---|---|
| Title | The best endoscopic procedure for diagnosing macroscopic type small flat adenomas, and for clarifing the features of type IIc | |
| Publish Date | 1998/01 | |
| Author | Shigeharu Kato | Department of Internal Medicine, National Cancer Hospital East |
| [ Summary ] | It is difficult to diagnose of macroscopic type for small flat adenomas with a depressed component, and whether or not it is depressed type (IIc)． The aim of this presentation is to determine the best endoscopic procedure for diagnosing macroscopic type small flat adenoma, and to clarify the features of type IIc. The macroscopic type was finally diagnosed stereomicroscopically. We studied correspondence of macroscopic type with the endoscope via ordinary and magnifying view with stereomicroscopic diagnosis of small flat adenomas less than 5mm in size. In flat elevated type (IIa), there were no differences in correspondent rate for final macroscopic diagnosis between ordinary and magnifying views. In flat type with a depressed component (IIa+dep,IIa+IIc and IIc), the correspondent rate for final diagnosis was higher in magnifying view (especially after crystal violet staining) than in the ordinary view. We felt magnifying findings with 0.05% crystal violet staining to be most suitable for diagnosing macroscopic type small flat adenomas with a depressed component. The IIIs pit pattern was observed in most of IIc lesions, moreover depressed margin with star or round-shaped lesions had a tendency to show higher grade atypism. Namely, typical findings of type IIc are obvious depression with star or round-shaped margin, and IIIs pit in the depressed area. However, we detected IIc lesions 5mm in size with a type IV pit pattern, and this lesion was diffusely stained with p53 in the tumor immunohistochemically. Thus, we suggest that IIc could not be diagnosed by pit pattern alone. |
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