Pop diva Kylie Minogue is undergoing medical tests in the Australian city of Melbourne in preparation for breast cancer surgery later this week, her management said in a statement on Thursday.

Initial tests showed the cancer was confined to the breast.

Minogue announced on Tuesday that she had been diagnosed with early breast cancer and postponed her Australian and Asian "Showgirl Tour" concerts.

"Kylie is currently undergoing tests at a first class medical facility in Melbourne in preparation for an operation this week by one of Australia's leading surgeons," said the statement.

"Thankfully, tests so far have confirmed the earlier diagnosis that the cancer appears to be confined to the breast."

Kylie Minogue rose from humble showbiz beginnings as a teenage actress in the soap opera "Neighbours" in the 1980s to international stardom as one of the world's top pop singers.

The music star, who is signed to EMI, is worth about A$60 million (US$46 million), according to a 2004 list of rich young Australians compiled by BRW magazine.