A family of Microsoft word processing software products for creating web, email, and print documents.
XE and TC fields are used to mark entries for inclusion in an Index and the Table of Contents respectively and they are formatted as hidden so that (normally) you would not see them, they would not print and they would not take up space in the document. If you have hidden text displayed however, they will appear in-line with the text and hence change the layout of the document.
If you are really worried about this matter, send me a copy of the documents and I will investigate the issue.