Canadian hard rockers Helix announced on Monday that longtime guitarist Brent "The Doctor" Doerner has stepped down from the band after more than three decades.  The band posted the following statement on its official website:  "Although we are sad to hear the news, we wish Brent all the best in his future. Brent is a huge part of the band and will be truly missed by fans from around the world to the Helix family. Brent's last shows will be September 28th at the Rockpile in Toronto and September 29th in Stratford, Ontario. Thanks for all the music and the lifelong memories you've brought to the band, Brent... YOU ROCK!!!"