Topics, no. Posts, maybe, depending on account restrictions on a new account. You might be able to erase the content of your posts using the edit function. But the mods won’t help you with this; MR believes in the integrity of discussions. Presumably you came here for help and now you’re done? It’s not very respectful to attempt to remove the traces. Similarly, while we’ll retire an account, we will not eliminate it.
Removing all traces of your activity makes threads difficult to follow (or destroys all usefulness).
As a frequent 'user helper', you just wasted MY efforts.

I bet you also tear pages out of books. Same end effect GAPS in the story