I know that Gerrit is well suited to do Code Reviews.
As want to move from existing tool to git/gerrit where word documents also need to be reviewed. Currently in-house review tool supports documents like word.
Whether is it possible to review documents like MS- WORD ( word ) document in gerrit with ease.
If not or difficult to review with word document , whether is it possible to integrate in-house tool in Gerrit and / or direct for certain file-types to use a different tool?
While possible in general (as you can checkout the change and open the document), this is not what Gerrit is made for. Gerrit is made for text files (mostly source code) that can be diffed.
While I agree with @StephenKing that this is not what Gerrit is made for, you can slightly facilitate reviews with certain types of files by adding the mimetype section in your gerrit.config, for example
[mimetype "application/msword"]
safe = true
This will allow to directly download docx files during review (and possibly, compare them locally). By default, when downloading a file from Gerrit, it creates a zip archive from it and makes it more difficult to compare & review.
Unfortunately, it seems that there is currently no way of viewing docx files in a browser. But if you set for example safe mimetype for pdfs, you can simply compare them in browser with gerrit.
