Scientists in Australia claim to have grown breast tissue on a pig - raising hopes that they can find new ways to help cancer patients who have lost theirs.
The technique could one day help women who lose a breast to cancer
They believe the technique, if replicated in humans, could be used to enable women who have undergone a mastectomy to go some way towards creating a new one.
The tissue was grown using the pig's stem cells or master cells which can develop into any other type of cell.
Scientists from the Bernard O'Brien Institute in Melbourne announced their results at the World Congress of Plastic Surgery in Sydney.
Other scientists have also succeeded in growing organs and tissue. However, this has traditionally been achieved only in the laboratory.
In this case, scientists managed to grow the breast tissue on the pig's body.
They appear to have achieved this by first creating a special "chamber".
This chamber is a small implant, which is specially designed to allow new blood vessels to grow inside.
According to the scientists, these blood vessels encourage the growth of body tissue. They do this by recruiting the body's own stem cells.
In this instance, the scientists were able to grow fat tissue inside the chamber.
They believe this type of tissue could, if grown in humans, be used to reconstruct breasts after cancer surgery.
In addition, it could also potentially be used to increase the size of a woman's breasts.
The scientists believe the technology could also have a role in repairing the damage to tissue and skin caused by burns or other accidents, cancers in other areas of the body and even birth defects.
"The technology, which we are currently producing, has allowed us to grow fat tissue," said Professor Wayne Morrison, head of the Bernard O'Brien Institute.
"We have been able to grow a breast in a pig using its own cells.
"We believe, therefore, that by using the chamber model we have created, we will have the potential to grow fat tissue within humans, which will assist in breast reconstruction, augmentation and contour filling."
One of the major benefits of growing tissue in this way, is that it would be much less likely to be rejected by the body.
Professor Morrison believes the technique could one day enable people to grow their own organs.
"We may also see that the need to transplant from one person to another may be eliminated. We can also transplant from one place in the body to another," he said.
"This development could see some types of organ transplants become obsolete in the next 10 years."
However, Professor Tim Hardingham, director of the UK Centre for Tissue Engineering in Manchester, said similar research has been carried out in the United States.
He questioned claims that the technique could be used in humans.
"The suggestion that this may be a way of developing breast-like material sounds like stretching it.
"One issue is that placing anything inside the abdomen is quite serious. There is a very high risk of infection so it is not something you would trivially do."