LOS ANGELES (Reuters) - Dana Reeve, the widow of "Superman" actor Christopher Reeve, announced on Tuesday that she had been diagnosed with lung cancer. Article Tools Printer friendly E-mail to a friend Nation RSS feed Available RSS feeds Most e-mailed More: Globe Nation stories | Latest national news | Globe front page | Boston.com Sign up for: Globe Headlines e-mail | Breaking News Alerts Reeve, 44, who put her own acting career on hold to nurse her husband after he was paralyzed in a riding accident, said in a brief statement she was undergoing treatment and was optimistic about the...