like chronic pain, infection and
lymphedema (a swelling of tissue,
often in the limbs), that commonly
follow lymph-node removal. It is
also saving lives. Recent studies
have shown that patients who
undergo sentinel-node biopsy
are less likely than those who
take a traditional watch-and-wait
approach to have a recurrence or
die of their disease.
CHALLENGING CELLS
Despite the numerous clinical trials
that have tested new drugs or
new drug combinations, only one
chemotherapy drug, dacarbazine
(DTIC-Dome), has been approved
to treat melanoma that has
metastasized, and even it is not
often effective. “Dacarbazine
only works in about 15 percent of
CR | Page No. 34 | Summer 2009
THE MELANOMA MNEMONIC
Keep an eye out for moles with these traits.
ASYMMETRY
One half doesn’t match
the other half.
BORDER
The edges are ragged,
blotched or blurred.
COLOR
The pigmentation is not uniform.
DIAMETER
The width is greater than
6 millimeters (the width
of a pencil eraser).
ELEVATION/EVOLUTION
The mole has different
elevations/contours or
has changed.
patients,” notes Gregory Daniels, a
medical oncologist who coordinates
the clinical program in melanoma
at the University of California,
San Diego. “And it has never been
shown to extend survival.”
other systemic treatments
for metastatic melanoma have
also been studied, but most have
been found to be ineffective or
not as effective as dacarbazine.
In the late 1980s, researchers
began investigating whether
the melanocytes would respond
to immunotherapy. To date,
investigators have identified
interferon-alpha and interleukin- 2
(IL- 2) as the two most effective
immunotherapy treatments. But as
with dacarbazine, “most effective”
is relative. Studies have shown
response rates for IL- 2 ranging
from 8 percent to 22 percent,
says Daniels adding, “while
these biologic agents can delay
recurrence in some patients, they
rarely provide a cure.”
This is why the melanoma field
did a double take when oncologists
at the Dana-Farber Cancer Institute
in Boston reported in the Journal
of Clinical Oncology in April 2008
that they had a patient with a
rectal melanoma whose tumors
shrunk dramatically in response
to imatinib (Gleevec). The drug
blocks a protein, called kit, which
is overproduced when the c-kit
gene becomes defective. The
investigators had decided to
explore whether imatinib might
be effective in melanoma after
another research group reported
it had found kit mutations in
21 percent of mucosal melanomas,
11 percent of acral melanomas, and
17 percent of melanomas arising in
chronically sun-damaged skin, like
that on the head and neck.
This finding has given
researchers hope that they
will now be able to offer some
metastatic melanoma patients
an effective treatment. “It’s only
a small number for whom it will
be effective—maybe 300 to
600 patients in the U.S.,” says
Meenhard Herlyn, a biologist at the
Wistar Institute, an independent
biomedical research center in
