Former Empress Michiko underwent a successful breast cancer surgery Sunday at the University of Tokyo Hospital, the Imperial Household Agency said.A lump was found in July in the 84-year-old former empress's left breast mammary gland during an echography exam and the cancer diagnosis was confirmed after a needle biopsy was conducted in early August.Former Emperor Akihito and the couple's daughter Sayako Kuroda visited the hospital Sunday.She had lost weight due to stress and a busy schedule amid the imperial succession earlier in the year, according to the agency. In June, she underwent cat…READ FULL ARTICLE