I believe that to do what you want do say, with the side effect of possibly leaving extra spaces in your topic: 
{ $topic =~ s/(^|\W)$_($|\W)/$1$2/g; }

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update yea yea, my original code was fscked up badly .. that's what you get for looking at what edits need to be done at the same time...

that is, look for the word between either the start of the starting or a non-word character, and either the end of the string or a non-word character. You might end up with consecutive spaces in the topic this way; you may want to consider using a placeholder to indicate you removed something (something as simple as BLEEP), but that's up to your project specifications.

Dr. Michael K. Neylon - mneylon-pm@masemware.com || "You've left the lens cap of your mind on again, Pinky" - The Brain

In reply to Re: Defenetly a complicated perl recipie with 2 arrays, 1 scaler and some special matching by Masem
in thread Defenetly a complicated perl recipie with 2 arrays, 1 scaler and some special matching by Anonymous Monk

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