Some liver damage caused by heavy drinking or hepatitis could be halted or even reversed, claim researchers.
Cirrhosis is a major killer in the UK
US researchers say that the growth of scarring around the organ might be stopped by blocking a vital protein which helps it to form.
The research, in the journal PLoS Online, could also eventually help patients with lung problems and burns.
The British Liver Trust said that any treatment which lessened scarring would help patients.
Heavy alcohol use and hepatitis can lead to a process called fibrosis in the liver, which involves the formation of excessive scar tissue.
Cirrhosis happens when this scarring becomes too severe, interfering with the way the liver works.
Currently doctors can do little more than try to prevent more damage by changing the patient's lifestyle or treating the virus which caused it.
The researchers at the University of California at San Diego School of Medicine have halted the formation of the scar tissue by blocking a protein called RSK, which is released naturally by the body as part of the healing process.
The scientists used mice with severe liver fibrosis, some of which were given a chemical which countered RSK.
Those mice had no further liver fibrosis, while those who didn't receive the chemical showed signs of more damage.
Dr Martina Buck, who led the study, said she felt that the treatment might be able to go further, and actually repair damage already caused.
"Our latest finding proves that we can actually reverse the damage," she said.
The researchers said that other conditions involving fibrosis, such as pulmonary fibrosis and scarring around burn injuries, could also potentially benefit.
A spokesman for the British Liver Trust said that the research was promising: "This is clearly in very early stages and the real test will be when a treatment is developed to safely block progression of damage in the livers of patients with liver disease and reverse their fibrosis.
"Irrespective of whether cirrhosis is fully reversible there is clearly a lot of benefit to be derived from reducing the amount of liver fibrosis as this allows the liver cells to resume normal function."