Problems with Grading of Dysplasia in Barrett’s Esophagus
Two principle problems interfere with the diagnosis and grading of dysplasia in Barrett’s esophagus: fixation and orientation.
Formalin is not the ideal fixative for nuclear detail, and we rely heavily on nuclear features for the diagnosis and grading of dysplasia. We use Hollande’s fixative, which is a modification of Bouin’s solution, for our biopsy material. We have had excellent results with this fixative, and if you compare the nuclear detail achieved with Hollande’s solution as compared to that achieved with formalin, the differences become obvious.
Another important element is proper orientation of the specimen. Surface epithelial involvement by atypical epithelium is an important criterion for the diagnosis of dysplasia. Improperly oriented specimens make it difficult to evaluate the surface epithelium and often result in the diagnosis of indefinite for dysplasia. Ideally, the endoscopist or an assistant should orient the biopsy onto a substrate, such as monofilament mesh, by teasing it out of the biopsy forceps and onto the tip of the finger. The biopsy can then be carefully flattened out on the fingertip, mucosal surface down, with the aid of the side of a dissecting needle, and can subsequently be transferred to the selected substrate with the mucosal surface up.
The use of the larger 3.4 mm forceps results in larger biopsies than the standard 2.4 mm biopsy forceps, and they are therefore best for diagnostic purposes. The larger specimens obtained with these forceps are easier to orient and have proportionately less crush artifact. The use of the large forceps is not associated with a higher risk of complications. In clinical research at the University of Washington, over 100,000 biopsies have been taken with the larger forceps without any increase in complications beyond that expected for the smaller forceps.