Researchers in the United Kingdom have performed a landmark procedure called chemosaturation that "bathes" the liver in chemotherapy drugs and sends only small amounts of the drug to the rest of the body.

Currently, chemotherapy drugs are used to treat cancer because they attack cancerous cells. They are administered through the vein. Because the drug circulates through the entire body, chemotherapy attacks healthy cells as well. The treatment is normally full of severe side effects, like fatigue, hair loss, and fertility problems.

Researchers believe that targeting the organ specifically means that side effects can be prevented. They also believe that, since other organs will be spared, higher dosages of chemotherapy can be given to patients.

The UK study focused on two patients with a rare form of eye cancer that had spread to their livers. Doctors inflated balloons in blood vessels on both sides of the liver to block it off. Then they pumped the liver full of chemotherapy. Lastly, they filtered the blood so that it was nearly free of the drug.

"To cut off an organ from the body for 60 minutes, soak it in a high dose of drug and then filter the blood almost completely clean before returning is truly groundbreaking...In 20 years' time the idea of injecting a drug which poisons the whole body for a cancer in just one small area will seem bonkers," Dr Brian Stedman, a consultant interventional radiologist, told BBC.

The surgery occurred within the past three months. Both of the patients appear to be doing well, and doctors say that their tumors are much smaller.

Researchers believe that the procedure could also be applied for other organs, like the pancreas, kidney, and lungs, or other organs that could be easily separated from the blood supply.

A similar study had been undertaken in the United States on patients with ocular melanoma that had spread to the liver. While patients who were given chemotherapy saw their tumors stop growing for a month and a half, those who were given chemosaturation saw their tumors stop growing for six months. Such patients normally only live for two to four months after treatment. The trial was so successful that all of the patients involved in the study were eventually given chemosaturation.

The technique has also been used in France, Germany, Italy, and Ireland.