The intense media coverage of Kylie Minogue's breast cancer diagnosis put extra strain on NHS screening services because it encouraged more "worried well" to seek treatment, according to a cancer specialist.

Chris Gateley said referrals to the Breast Unit at Royal Gwent hospital in Newport, south Wales, jumped 61% in the month following Minogue's diagnosis in May 2005 but there was no increase in the number of actual cases.

He said colleagues around the country had told him they had seen similar increases and if the Newport rise was reflected nationally it would mean there were around 30,000 extra referrals in the month after Kylie's announcement.

"We didn't find a single extra breast cancer case than we would have expected," he said. "The extra press attention causes anxiety. This group of women are called the worried well. They have symptoms that are completely innocent."

There are around 44,000 cases of breast cancer a year, but 93% of women referred turn out to be free of the disease.

Mr Gateley added that the Gwent clinic - which received 322 referrals compared to between 150 and 200 in a normal June - took a year to get back to the national target of seeing all cases within 10 days.

The 38-year-old singer appeared on stage in Melbourne with her sister Dannii this month. After a partial mastectomy, chemotherapy and radiotherapy Minogue was pronounced cancer-free in January.

The charity Breakthrough Breast Cancer said it had thousands more web hits and calls following Minogue's announcement. "What's encouraging is that all age groups, including women over 50, who are at greatest risk from the disease, are becoming more breast aware."