For men having prostate cancer surgery, the type of anaesthesia doctors use
might make a difference in the odds of the cancer returning, a new study
Researchers found that of nearly 3 300 men who underwent prostate cancer
surgery, those who were given both general and regional anaesthesia had a lower
risk of seeing their cancer progress than men who received only general anaesthesia.
Over a period of 15 years, about 5% of men given only general anaesthesia
had their cancer recur in their bones or other sites, the researchers said.
That compared with 3% of men who also received regional anaesthesia, which
typically meant a spinal injection of the painkiller morphine, plus a numbing
None of that, however, proves that anaesthesia choices directly affect a
prostate cancer patient's prognosis.
"We can't conclude from this that it's cause-and-effect," said
senior researcher Dr Juraj Sprung, an anaesthesiologist at the Mayo Clinic in
But, he said, one theory is that spinal painkillers like the opioid morphine
can make a difference because they curb patients' need for opioid drugs after
surgery. Those post-surgery opioids, which affect the whole body, may decrease
the immune system's effectiveness.
That's potentially important, Sprung said, because during prostate cancer
surgery, some cancer cells usually escape into the bloodstream and a fully
functioning immune response might be needed to kill them off.
"If you avoid opioids after surgery, you may be increasing your ability
to fight off these cancer cells," Sprung said.
The study, reported online in the British Journal of Anaesthesia, is
not the first to see a link between regional anaesthesia and a lower risk of
cancer recurrence or progression. Some past studies have seen a similar pattern
in patients having surgery for breast, ovarian or colon cancer. But those
studies, like the current one, point only to a correlation, not a
cause-and-effect link, Sprung said.
Minimally invasive approach
Dr David Samadi, chief of urology at Lenox Hill Hospital in New York City,
agreed. "We have to be very careful about how we interpret these
results," said Samadi, who was not involved in the new study.
One important issue, he said, is that the men in this study all had open
surgery to remove their prostate gland.
But these days, the surgery is almost always done laparoscopically – a
minimally invasive approach in which surgeons make a few small incisions. In
the United States, Samadi said, most of these procedures are done with the aid
of robotic "arms".
Compared with traditional open surgery, laparoscopic surgery is quicker and
causes less stress, blood loss and post-surgery pain, Samadi said. And in his
experience, he said, patients' need for opioids after surgery is low.
Sprung agreed that it's not clear whether the current findings extend to men
having laparoscopic surgery.
The findings are based on the records of nearly 3 300 men who had prostate
cancer surgery between 1991 and 2005 at the Mayo Clinic. Half had been given
only general anaesthesia, while the other half had received regional anaesthesia
as well. In 83% of the cases, that meant a spinal block containing morphine.
Risk generally low
The researchers weighed other factors, such as the stage of the cancer and
whether a man received radiation or hormone therapy after surgery. In the end,
having general anaesthesia alone was linked to a nearly threefold higher risk
of a cancer turning up in distant sites in the body over the next 15 years.
Still, only 3% to 5% of the men had a cancer recurrence. And, Samadi said,
the risk is generally low with a skilled surgeon. He suggested that patients be
more concerned about their surgeon's experience than the type of anaesthesia.
Studies have found that prostate cancer patients treated by more experienced
surgeons tend to have a lower risk of recurrence, Samadi said. They also have
lower rates of lasting side effects, such as erectile dysfunction and
"It's not the robot," Samadi said. "It's the experience of
To prove that regional anaesthesia directly affects cancer patients'
prognosis, "controlled" studies are needed, Sprung said. That means
randomly assigning some surgery patients to have general anaesthesia only,
while others get regional anaesthesia as well.
For now, Sprung said, the decision about whether to use a spinal painkiller
during surgery should be based on other factors, such as its potential to limit
Find more information on cancer here.
The American Cancer Society has more information on prostate cancer surgery.