A new study reveals patients with liver cancer who
have no other treatment options might benefit from more aggressive
operations once considered too risky, report University of Florida
scientists, who also published research this month yielding insight into
ways to protect the liver during surgery.
The number of Americans battling liver disease, meanwhile, is expected
to increase, especially as the obesity and diabetes epidemics fuel
conditions that damage the organ, UF researchers say. One in 10
Americans currently has liver disease, according to the American Liver
Foundation, and liver disease often contributes to the development of
cancer. The American Cancer Society estimates that 21,370 new cases of
liver cancer and 18,410 related deaths will occur this year.
Surgeon Alan Hemming, M.D., chief of transplantation and hepatobiliary
surgery at UF's College of Medicine, has shown that using a more
aggressive approach to liver surgery can prove successful in patients
who were deemed inoperable by traditional standards.
"We are doing things that are very complex that could not be done a few
years ago and yet getting the same success rates that standard, less
complex liver surgery was getting 10 years ago," said Hemming. "If you
are a patient who is told you only have six months to live and there are
no options but then all of a sudden you are given a more than 30 percent
chance of survival with admittedly complex surgery, you would think that
is a good option."
Published in this month's Journal of the American College of Surgeons,
Hemming's 10-year retrospective study focuses on 116 patients who were
initially told by an outside hospital routinely performing liver
surgeries that they were not candidates for an operation. These patients
ultimately underwent more aggressive surgery at Shands at UF medical
center. Approximately one-third of patients survived five years or more,
despite an initial prognosis that they had just a few months to live.
UF surgeons used a combination of surgical techniques taken from both
transplantation and surgical oncology, including chemotherapy,
performing procedures in stages, reconstructing the liver's vascular
system and using surgery and radiofrequency ablation together, said
Hemming, who directs the UF Center for Hepatobiliary Disease.
"Surgical removal of liver tumors offers the best chance at long-term
survival for patients with cancers of the liver," said Todd W. Bauer,
M.D., a surgical oncologist at the University of Virginia School of
Medicine. "Over the past 10 years, significant advances have been made
in the field of liver surgery which allow surgeons to perform
potentially curative resections more safely for a greater number of
patients and with better long-term survival. These outstanding results
by Dr. Hemming and colleagues fully illustrate this progress."
Hemming said the work UF basic science researchers are conducting to
identify ways to protect the liver during surgery also could help
increase the number of patients who could benefit from liver surgery and
possibly make more livers viable for transplantation.
Although unique because of its ability to regenerate, the liver is
actually quite delicate and can easily be irreversibly damaged during
surgery or transplantation. Composed of a large amount of blood -
approximately 20 percent - the liver is greatly affected when the blood
supply is cut off during surgery. This causes ischemia, which leads to a
lack of oxygen to the organ.
"Paradoxically, ischemia is OK, but the real problem is when blood
returns to the liver," said principal investigator Jae-Sung Kim, Ph.D.,
a UF assistant professor of surgery and of pharmacology and
therapeutics.
As blood and oxygen flood the organ, the natural process by which cells
eliminate their own weakened components to increase their longevity -
called autophagy - malfunctions, causing damaged cells to build up
within the liver.
So far, attempts to limit the effects of this type of injury have not
been successful. UF study findings published this month in the journal
Hepatology reveal the underlying problem is caused by more than one
factor and that the cell's "power plant," known as mitochondria, is one
of the crucial elements.
"We found that if we use the autophagy process and selectively remove
damaged mitochondria, it actually keeps the cell alive after the
oxygenated blood is delivered back to the liver," said Kim.
In animal studies, UF researchers found the activation of a key enzyme
that is naturally produced when oxygen returns to the liver depletes two
proteins that help regulate the cell's ability to dispose of its
weakened elements.
"As cellular levels of these proteins are depleted, cell and tissue lose
control, and the liver loses viability," Kim said.
Kim said the next step is to work with pharmacologists to develop drug
treatments that will bolster the proteins to keep the cell's natural
house-cleaning process on track, preventing cellular injury and
improving liver function after surgery.
Bauer added that this research moves the field one step closer to
identifying drugs that could prevent liver damage during surgery,
helping to reduce complications at a time when liver disease is on the
rise.
"Since liver diseases are steadily increasing due to increased
prevalence of metabolic diseases such as diabetes, fatty liver and
obesity, more patients may need liver surgery in the near future," Kim
said.
The University of Florida Health Science Center - the most comprehensive
academic health center in the Southeast - is dedicated to high-quality
programs of education, research, patient care and public service. The
Health Science Center encompasses the colleges of Dentistry, Public
Health and Health Professions, Medicine, Nursing, Pharmacy and
Veterinary Medicine, as well as the Veterinary Medical Teaching Hospital
and an academic campus in Jacksonville offering graduate education
programs in dentistry, medicine, nursing and pharmacy. Patient care
activities, under the banner UF&Shands, are provided through teaching
hospitals and a network of clinics in Gainesville and Jacksonville. The
Health Science Center also has a statewide presence through satellite
medical, dental and nursing clinics staffed by UF health professionals;
and affiliations with community-based health-care facilities stretching
from Hialeah and Miami to the Florida Panhandle.
University of Florida Health Science Center