Updating Test Cases via import

[JudeLabs]

I found that issues can be imported from CSV.  And in order to do an updates via import you can add a "Issue Key" column where you can put in the specific issue key and upon import,  that issue is updated.

"Updating Existing Issues"

https://confluence.atlassian.com/adminjiracloud/importing-data-from-csv-776636762.html

However,  I would like do the same thing with test cases in TM4J.  but it does not seem to work when I import with a test case key.   Can we update test cases via CSV import? If so,  how?