This can be argued as just an extension of Roe v. Wade.  If a woman has a total right to do anything with her body, so should a man.  If a person has a total right to do anything with their body, voluntary termination is included.  

The only question is how humane the process should be.  The technology exists for it to be much more humane and less traumatic for the survivors  than a shotgun under the chin.