TOKYO, JAPAN — Japanese researchers have achieved a major breakthrough in regenerative medicine for breast cancer patients, Japanese news agency Jiji Press reported.

The researchers succeeded in having breast cancer patients recover what was lost after breast-conserving surgery, an operation to remove breast cancer and not breast itself by transplanting fat mixed with their own stem cells.

The achievement was made by a team of researchers led by Bin Nakayama, associate professor at Tottori University during clinical testing conducted between September and January on five women aged between 30 and 60 who underwent breast-conserving surgery.

Durng the tests, fat taken out of the patients’ abdomen or hips and mixed with their stem cells was transplanted into where tumours and surrounding tissues were removed.

The researchers said that if only fat is transplanted, most of it is absorbed into the body and about 30 per cent of it remains as it does not have blood vessels.

Between 70 to 90 per cent of transplanted fat remained after blood vessels were newly formed in the fat.

Stem cells are apparently capable of helping bring blood vessels into fat from surrounding tissues, the researchers added.

According to the Japanese Breast Cancer Society, some 60,000 Japanese develop breast cancer a year with 60 per cent undergoing breast-conserving surgery.