Andractim is a gel that contains DHT. It is used by transsexual females that want to become male and also by teenagers to help improve penis growth in males are that developing slower than normal.
Yes a lot of bros have reported decent results applying the DHT cream on the chest, but I would use arimistane instead for this purpose. So not that it doesn't work, it is just that there are much better options on the market right now.