Current research offers hope for liver cancer patients
Friday, 30 June 2000
Cancers of the colon and rectum are among the most common. While early diagnosis offers good prospects for their treatment, many are diagnosed at a late stage. By then, a colo-rectal cancer which is in itself treatable has often spread to the liver.
Cancers of the liver are generally incurable. Only about 20% of livers diseased with tumours can be treated at present, and even then only with difficulty. Because the liver is essential for life and health, surgery is impossible when it involves the removal of excessive amounts of liver tissue. Transplants usually can not be considered.
A medical research team from Adelaide University has begun final trials on a new and promising treatment for these liver tumours. The surgeons, based in the Department of Surgery at Adelaide's Queen Elizabeth Hospital, are now tackling liver tumours with electrolysis.
Electrolysis involves passing an electric current through the liver, a process that produces chemical and physical changes. Electrolysis can split water into oxygen and hydrogen, or produce strong acids and alkalis from neutral solutions.
The surgical team has developed techniques for inserting electrodes into a liver tumour and using low voltage to move ions between them, liberating toxic substances that destroy the tumour chemically. The current can be controlled to deliver a predictable dose-dependent response over time, and even very large tumours can be treated.
"The tumour isn't burned,' explained Research Assistant Ms Paula Baxter, 'the current is too low. We have an apparently safe process of destroying the tumour with the chemical action of electrolysis."
The technology has been developed conjointly with the University of Leicester. Over the last 4 years, 5 doctors from Leicester have been collaborating with the Adelaide team, led by Professor Guy Maddern.
"This is a technique and a technology that has not been used anywhere else in the world for this sort of condition," said Professor Maddern. "It is now being published in recognised journals and we hope that if we can get it working efficiently, it will be picked up around the world," he said.
"By placing the electrodes very carefully into the tumour, we hope to treat patients without resorting to major surgery,' said Dr Guy Finch. 'We might even see the day when electrodes are left in the liver for several weeks, and patients come into the clinic for several sessions of treatment until the tumour is destroyed. It would be simple to manage, causing little discomfort and minimal disruption to patients' daily lives," he said.
Following initial work on animals, a pilot study on five patients showed complete tumour destruction in all cases. That trial led to the use of electrolysis to treat three further patients with inoperable liver tumours. A surgical procedure on one patient 12 months later showed no trace of the original tumour, and that patient is now at 20 months follow up. The other two patients are currently at 14 and 12 months follow up, and neither shows any evidence of liver tumours.
"The patients we've treated to date have all gone well," said Professor Maddern. "They continue to be so, and some of them are now alive and well at a period of time greater than twelve months," he said.
"I think that this is not going to be a cure-all for all people," said Professor Maddern, "but I think for those who have cancers in the liver that are considered to be inoperable, this makes the patients potentially operable," he said.
"If in the future the disease returns, after what we thought was a curative operation, we may well be able to treat these patients without the need for surgery," said Professor Maddern. "We expect that the technique will improve a lot over the next 12 months."
For any new form of cancer therapy to become accepted in clinical practice, it must be shown to improve patient survival. This is best shown by a 5-year follow up of a controlled clinical trial of patients with inoperable disease.
The Department of Surgery is very keen to have any patients with known liver cancers referred to them to be assessed for their suitability for electrolytic treatment.
Arrangements can be made directly with Professor Maddern's receptionist at the Queen Elizabeth Hospital ph (08) 8222 6750.