Labor leader Bill Shorten is promising to boost funding for Medicare by $47 million to provide affordable access to breast cancer scans and drive down the cost of cancer treatment.

"Medicare already subsidises similar MRI scans for men with prostate cancer - but not for women with breast cancer, except in extremely limited circumstances," Mr Shorten said on Friday.

"As a result, thousands of women are being charged up to $1500 in out-of-pocket costs for the scans used to diagnose their cancer, decide on treatment and ensure cancer does not return."

The cost of multiple scans can add up to many thousands of dollars.

Health Minister Greg Hunt is also promising to boost Medicare funding by $32.6 million for breast cancer scans.

Mr Hunt expects about 14,000 per year to benefit.

The government is also planning to add PET scans for advanced breast cancer to the Medicare list from November this year, helping about 10,000 patients save up to $1000 per scan.

"These scans will save lives and reduce out-of-pocket cost for families fighting breast cancer," Mr Hunt said.

Labor health spokeswoman Catherine King said the cost added significantly to the stress women were already going through as they dealt with a cancer diagnosis.

"In the worst-case scenario, some women may forego these scans altogether because they simply cannot afford to pay the high out-of-pocket costs," she said.

Labor's Medicare items will be designed in consultation with experts, and the extra funding would come from closing multinational business tax loopholes.

Australian Associated Press