Misbehaving and emotion children are always difficult to deal with.
However, you do have a few options.
I would recommend taking him into a child psychologist, especially if it is considerably bad. If he's constantly throwing tantrums on a moments notice for no apparent reason, I would advise talking to a professional. They will be able to assess the parent/child relationship, mental stability of the child, and whether or not the child will need medical help or medication. If it's as bad as it seems, I would definately go to a child psychologist.
Another option would be to ignore his tantrums. Many children misbehave or throw a fit because they know it gives them what they want or the attention they get.
Consider the child in the grocery store that screams evertime the parent refuses to buy them candy. If the parent gives in every time the child screams, consequently, the child learns that screaming equals candy. If the parent were to ignore the screaming child and dicipline him (i.e. "Go out and sit in the car until you can learn to be better behaved.") then the child would learn that screaming isn't going to get him the candy.
The same could be applied to a "hot headed 10 year old." If your child is screaming and becoming pissed off because he or she knows it will get them candy or attention, they will continue to do so until taught otherwise.
Dicipline is key to forming good children. Now, dicipline may not be the action needed in this case, I know not considering I don't know all the details, however, usually it comes down to the fact that the child needs to be diciplined and learn that being "hot headed" wont get them anywhere.
I hope this helped, and good luck. If you want/need to know anymore information, feel free to email me: chikusho_kidd@yahoo.com