New Arthritis Drugs: Skin Cancer Risk
Study: Slightly Higher Skin Cancer Risk With Remicade and Enbrel
Aug. 29, 2007 -- Rheumatoid arthritis patients on Remicade or Enbrel have a
small but higher risk of skin cancer, a new study confirms.
The finding -- from 13,001 rheumatoid arthritis patients who twice a year
completed detailed health questionnaires -- underscores recent evidence that
higher doses of new arthritis drugs increase patients' cancer risk.
The new study contradicts earlier findings that the new drugs raise
patients' risk of solid
tumors. But it supports earlier findings linking the new "TNF
blocker" drugs to skin cancers, including potentially deadly melanomas.
Even so, the small risk does not outweigh the benefit for patients who truly
need the new drugs, says study investigator Frederick Wolfe, MD, director of
the National Data Bank for Rheumatic Diseases.
"These drugs, at this moment, don't seem to add any risk except for skin
cancer and melanoma," Wolfe tells WebMD. "It is a small overall risk
and I don't think people should be concerned."
The findings appear in the September issue of the journal Arthritis &
Rheumatoid Arthritis Drugs
Rheumatoid arthritis is an immune disease. So-called "TNF blocker"
drugs interfere with an immune-system signal called tumor necrosis factor
alpha, or TNF-alpha. That can be a huge benefit to people crippled by
rheumatoid arthritis. But it can also expose patients to risks of serious
infections and cancers.
Three of these drugs are approved in the U.S.: Remicade, Enbrel, and Humira. The Wolfe study,
conducted from 1998 through 2005, included very few patients on Humira. Most of
the study patients taking TNF blockers in this study used Remicade.
analysis of TNF-blocker clinical trials focused on Remicade and Humira (an
update including Enbrel data is in the works). One of that study's
investigators, Mayo Clinic rheumatologist Tim Bongartz, MD -- not a participant
in the Wolfe study -- says Wolfe's findings are similar to those of Swedish
investigators who also found a link between skin cancer and TNF blockers.
"Three major clinical trials, in their malignancy data, all have some
indication there is a problem with skin cancer with these drugs," Bongartz
tells WebMD. "This has huge implications in how we examine these patients
and how we advise these patients."
Bongartz suggests doctors should do regular, thorough, whole-body skin
examinations for every patient taking TNF blockers.
Wolfe is less concerned.
"If there is a real message in these studies, it is that the overall
risk of cancer is small in rheumatoid arthritis patients," he says.
"The overall effect is to say things are much the same as they have been
over the last several decades. That is reassuring with these new drugs. ... I
don't think people should be concerned. It may be these drugs turn out to be
safe. It looks as though they are, and I am not particularly worried."
Bongartz says the real cancer risk of TNF blockers remains an open question.
Apart from the question of cancer, Bongartz is certain that these drugs do
increase a person's risk of a serious infection. But even this, he says, is no
reason for patients who need the drugs to stop taking them.
"It just tells doctors something about how to manage these
patients," Bongartz says. "If someone turns up in the emergency room
with vague symptoms, if that patient is taking a TNF blocker, the doctors
should be more alert."
recent two-year study found the TNF blocker Enbrel to be safe in the
long-term treatment of psoriasis.