Los Angeles Feb 20: Bruce Dickinson the lead singer of heavy metal English band Iron Maiden has undergone a seven-week course of chemotherapy and radiology treatment for tongue cancer. The 56-year-old English singer was treated after doctors found a small cancerous tumour at the back of his tongue reported Aceshowbiz. The course finished yesterday. The band announced the news in a statement posted on its website yesterday. (Read: What are the surgical options for oral cancer?) Just before Christmas Maiden vocalist Bruce Dickinson visited his doctor for a routine check-up. This led to tests and biopsies which revealed a small