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What Five Years Really Means
Survival statistics mean different things for different cancers.
By Curtis Pesmen
Looking back, I'm surprised by how calm I was on my recent
five-year anniversary of my last chemotherapy treatment for stage
3 locally advanced colorectal cancer. After speed-dialing my cell
phone for messages, and getting the “all clear” via
voicemail, I didn’t even pull the car over to celebrate.
This was night-and-day behavior for me compared with how jumpy,
giddy and excited I was (I even found myself singing) at my two-year
survival anniversary back in fall 2003.
Don’t get me wrong, I realize Year Five is a malignancy
milestone. Of the nation’s more than 10 million cancer survivors,
more than six million have survived beyond five years, reports
the National Cancer Institute. And some 14 percent, or more than
1.4 million, have lived more than 20 years beyond diagnosis. These,
too, are milestones—with, at times, confusing meanings.
Making Five Years Count
In brief, “five-year survival” is a term doctors and researchers use as a benchmark—between themselves. It allows them to compare cases, not predict. And it’s not “five-year cure” for a couple of reasons. Most importantly, five-year survival doesn’t mean you will only live five years. Instead it relates to the percentage of people in research studies who were still alive five years after diagnosis. (When you read of “relative” five-year survival, this refers to subjects who died of non-cancer causes—say a heart attack—that have been removed from the survival rate for that treatment. It makes for a more accurate statistic.)
In brief, "five-year survival" is
a term doctors and researchers use as a benchmark—between
themselves.
In general, the reason patients latch onto five-year survival
stretches back to the years prior to World War II when very few
people survived cancer. According to epidemiologist Phyllis Wingo,
PhD, chief of the Cancer Surveillance Branch at the Centers for
Disease Control and Prevention, five-year survival rates were introduced
in the 1930s not to point patients toward notions of a cure, but
because cancer specialists back then considered five-year survival
a nearly unattainable goal.
For survivors like me, any “what are my chances?” statistic
we hear from our doctors in the first year of treatment tends to
burrow into our brains and remain. “Of all recurrences in
colorectal cancer, 80 percent recur within the first two years,” Alan
Venook, MD, associate chief of the medical oncology division at
UCSF Comprehensive Cancer Center in San Francisco, told me after
Year One. Right then, I psychologically steeled myself to gird
for Year Two. Why should five years mean so much more? The answer:
It depends on the type of cancer you’re facing. Mine happened
to have a critical Year Two, but it’s different with breast
or other cancers. And more often than not, oncologists will consciously
refrain from using the phrase “five-year cure.”
According to the most recent data collected by the NCI, the
five-year survival rate for colorectal cancer is 63 percent. For
breast cancer it’s 86 percent, while for cancer of the lung,
the five-year rate is just 15 percent. “Different scenarios
have different landmarks,” says Dr. Venook. “Breast
cancer and prostate cancer might have very long trajectories [of
survival after five years], while pancreas cancer does not.” Still,
Dr. Venook considers the five-year survival stat, which is helpful
if not exactly precise, to be “an important landmark.”
“This notion of ‘five years’ has taken
on mythical proportion,” says Julia Rowland, PhD, director
of the NCI’s Office of Cancer Survivorship. “It used
to be if we got to that point, you would be cured. [But] we still
don’t say that.”
Rowland says today, doctors have what in business might be
called a “high-end” problem. Beyond recurrence for
the original cancer, other common post-five-year survival issues
include anxiety and depression, second cancers (for example, leukemia
as a result of radiation) and a variety of other possible late
effects from therapy. “It’s terrific that we can control
cancers in patients for long periods of time,” Rowland says. “But
this also allows them to experience such things as fatigue and
chemobrain in the short term, and then long-term effects for some
that may last for years.”
“The natural history of each cancer and its survivability
differs widely,” says Patricia Ganz, MD, director of the
division of cancer prevention and control research at UCLA’s
Jonsson Comprehensive Cancer Center. She says cancer cells with
short, reproductive doubling times, such as testicular cancer and
some leukemias, may be more apt to reach the level of medical cure
after five years. For instance, if a testicular cancer patient
is treated and two years later has a tumor marker test, “and
there’s no evidence of cancer coming back, then, for all
intents and purposes he is cured,” Dr. Ganz says. “This
cancer is not going to come back.”
But solid tumors, such as breast, colorectal and prostate
cancers, that have cellular doubling times of 100 days or longer,
remain a more mysterious animal. Their microscopic cells can hide,
even through apparent remission, evading screening techniques.
Long-term behavior of these tumors is tougher to predict, thus
the language of survival rates instead of cure.
“I couldn’t wait to put it behind me,” says
Karen Levine, a 49-year-old breast cancer survivor, acupuncturist
and mother of two from Boulder, Colorado, who recently passed her
five-year mark, cancer-free. “It is what it is, but I can
also move on.”
Doug Kennedy, Levine’s husband and a chiropractor,
adds, perhaps a bit more cautiously, “As someone working
in the medical world, I understand that five years isn’t
like taking an elevator to another level where we can be totally
relaxed. But our consciousness has changed. It’s allowed
us to take a deeper breath. Maybe 20 to 25 percent more relaxed.”
In the short run, says Dr. Ganz, many patients receive a
disease-free interval where they can lead a productive life. “But
there’s nothing magic about five years. And in breast cancer,
we should probably be looking at 10 years [as a more helpful guide].”
The Language Problem
No matter the numbers, “cancer-free” doesn’t
equal “cure.” When I first asked my medical oncologist
Dr. Venook what my chances of cure were, he didn’t directly
answer. Now, looking back five years, I know why. He tells me he
rarely, if ever, uses the word cure in discussing gastrointestinal
cancer prognoses with his patients. When delivering news and updates
to patients, “I always emphasize that five years is a point
beyond which there are very rare occurrences,” Dr. Venook
says, “but they do happen.”
He told me whatever the survival rates might be, my case
didn’t exactly apply. And he wasn’t being coy. Truth
is, at 43, I was younger than most patients in colorectal cancer
studies. I also had been treated with somewhat aggressive, experimental
chemotherapy and radiation. So we settled on a figure I was comfortable
with: There was nearly a 60 percent chance I would be alive in
five years based on “current” statistics of patients
in similar treatment situations.
“I’m a 10-year survivor now,” says Richard
Boyajian, a 39-year-old oncology nurse practitioner at Dana-Farber
Cancer Institute in Boston who fought chronic myeloid leukemia. “The
way I view it, it’s like getting your AA [Alcoholics Anonymous]
chit. You’re only as good as your next drink. I’m kind
of ambivalent about the term. But don’t get me wrong”—he
says with a bit more gravitas—“it might be a nice goal
when you’re not yet five years out.”
"Yes, 10 is good. And 20 will be better. But
I’m into 50. That’ll give me something to celebrate.’’ —Karen
Pollitz
Matthew Levett, of San Francisco, is a two-and-a-half-year
colon cancer survivor. “At five years, I want to gather friends
and loved ones—celebrate life, my marriage. Maybe the cancer
is just a really good excuse to do some celebrating that’s
worth doing anyway.”
Levett says on another level, he thinks it’s important
to commemorate survivorship occasions, particularly five years. “I
want to mark it big and loud.”
The Plus-Five Years
The other problem with survival language is comparing apples
with applesauce. By their very nature, even the most recent five-year
survival statistics are at least six years old. As Dr. Ganz explains,
in order to collect and publish meaningful data that can be used
in 2007, you need to go “back five years when the treatment
started, plus allow for time to gather and publish the results.”
Six years ago, Avastin® (bevacizumab), Erbitux® (cetuximab)
and Herceptin® (trastuzumab), among other groundbreaking
anticancer agents, either weren’t approved or didn’t
have widespread use among colorectal and breast cancer patients.
So chances are, says Christy Russell, MD, co-director of the USC/Norris
Lee Breast Center at the Keck School of Medicine in Los Angeles,
even the best five-year data will be less optimistic than today’s
survival odds for patients who received these newer treatments
since 2000. She says it’s not that the data are bad; it’s
the technical nature of performing accurate, long-term survival
studies.
“We can now put women with metastatic cancer into remission
for long periods of time, but we cannot promise them a cure,” Dr.
Russell says. For the tough cases like metastatic breast cancer,
she says, “People would say, on average, survival is about
three years. That’s not my experience any longer. That number
is not reflective of current therapy.
“There is always a lag between research and your [particular]
case. So when people with metastases ask me, ‘How long do
I have to live?’ I tell them, ‘I have some cases that
are similar who have lived less than a year. And some who are alive
at 15 to 20 years with advanced disease.’”
Smack in the middle of those numbers sits Year 10. And smack
in the middle of Karen Pollitz’s downtown Washington, D.C.,
office at Georgetown University sits a colorful crayon-crafted
sign that reads: “Happy 10th Anniversary!!!” Created
by the Pollitz kids, the abstract artwork doesn’t, however,
refer to a wedding day.
As Karen Pollitz, 48, recalls, “My anniversary dates
are still depressing. I was [only 37] when this happened. I got
up one morning. A mammogram was just another thing to do that day.” Until
it came back suspicious, and a biopsy confirmed breast cancer.
“Now, in terms of anniversaries,” Pollitz says, “it’s
mostly that I wish that hadn’t happened. I remember when
the doctor first told me about the five-year survival rates. Then
I said, ‘What have you got in terms of 50-year survival rates?’ I
mean, my daughter was just beginning kindergarten. [My doctor]
said, ‘That’s not how we count it. We count it in ‘fives.’”
“It’s a crappy disease,” says Pollitz,
who for years has researched ways in which cancer patients and
survivors can obtain health insurance and coverage for their disease-free
futures. “Yes, 10 is good. And 20
will be better. But I’m into 50. That’ll give me something
to celebrate. I’m holding out for 50.”
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