Leonardo DiCaprio ditches the models to party with his peers as he celebrates 50th birthday with Paris Hilton, 43, Katy Perry, 40 and his long-time buddies
          
           

Leonardo DiCaprio ditches the models to party with his peers as he celebrates 50th birthday with Paris Hilton, 43, Katy Perry, 40 and his long-time buddies  

Leonardo DiCaprio got his 50th birthday celebrations off to an early start on Saturday night as he threw himself a lavish party in Los Angeles with a…