Tim Allen has agreed to drop an $8 million libel lawsuit “out of humanitarian reasons,” says his attorney, after the “Home Improvement” star learned the defendant has brain cancer. Allen, who maintains a home in the Detroit suburb of Beverly Hills, filed the lawsuit last year in a Michigan county court against 73-year-old Henry Armstrong of Studio City, Calif., alleging that Armstrong gave false statements to the National Enquirer for his own financial benefit. The lawsuit accused Armstrong of telling the tabloid in 1997 that Allen appeared “drunk or high” when the actor struck him with his sports car. The case involving Armstrong’s suing Allen over the car accident was dismissed in May.