Former Empress Michiko has been diagnosed with early-stage breast cancer and will have surgery as early as September, the Imperial Household Agency said Friday.

A lump was found last month in her left breast's mammary gland during an echography exam, the agency said. An imaging scan later found that it could possibly be a malignant tumor.

The 84-year-old will have surgery after taking a rest this month in Karuizawa, Nagano Prefecture, with her husband, former Emperor Akihito, 85, who abdicated at the end of April.

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