Gosh, that's a hard one... What a wonderful acomplishment!! 
If I come up with something I'll let you know~ Good luck! I'm sure you'll come up with something!
NA progams are big on "coins/mediallions that signify them being clean and sober.
here is a link to the mediallion:
http://www.na.org/catalog/tags.htm
perhaps a cake with mediallion on it and just saying something like congratualtions on your on your one year anniversary.
or a cake with the serenity prayer on it. That is what a recovery addict live each day by..
What a great accomplishment!
How about relating it to a "twelve step" theme....but make each step decorated for a different "month"...to symbolize a drug free "year"! The cake could be like stepping stones or built up to make a stairway!
Hope this helps! 
I would just say "Great Job - his name" or "We are proud of you" with his name and just decorate in masculane colors. I think they will appreciate they great tasting cake and you will get your point across instead of bringing too much reminder of being off narcotics.
Hey guys,
I actually found out that it is his 8 yr anniversary 
so I have come up with making 2 10 inch double layer round cakes and placing them beside each other to form the number 8. the top circle I am going to do a b/c transfer with the narcotics anonymous logo done and some flowers around it then the bottom circle will say congratulations Darren on your 8 years of being clean and strong and some more type of flowers. It will all be done in roayl blue and white as that is the colors of the n/a logo. I am doing it tomorrow and will post pictures once I am done.
Thanks for the help
Shayla
That sounds great! Even if it was a year of being free from drugs I would have made a BIG deal about it!! 8 years!! Wow!!! Can't wait to see your pictures~
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