Texas ? Women who get lumpectomies for breast cancer may one day have a simple option involving stem cells for reconstructing the affected breast, researchers reported Saturday.

Doctors in Japan used stem cells derived from liposuctioned fat to repair the craters left in 21 women’s breasts when cancerous lumps were cut out.

The lead investigator, Dr. Keizo Sugimachi, reported at the San Antonio Breast Cancer Symposium that the procedure was safe and well tolerated in all 21 subjects, with no signs of rejection. There was a significant improvement in breast volume, and eight months later most of the women were satisfied with the outcome.

Doctors not involved in the study were cautiously optimistic the new technology might work.