“Carol
MacKenzie had just finished playing a round of golf when she noticed some
swelling and pain in her neck. It was 2014, and 18 years had passed since Ms.
MacKenzie finished treatment for breast cancer. But it had returned. This time
the cancer was growing inside several lymph nodes around her neck, plunging her
back into treatment long after she thought that was all behind her.
Doctors do not know exactly why or
how breast cancer can go dormant in a patient’s body for so long, not advancing
for years, until it suddenly begins to grow. But that’s what had happened.
Without treatment, Ms. MacKenzie’s cancer would most likely have made its way
to her vital organs and killed her.
But in the nine years since Ms.
MacKenzie’s cancer reappeared, her physician, Dr. Nancy Lin, a medical
oncologist at Dana-Farber Cancer Institute in Boston who specializes in
treating and studying advanced breast cancer, has prescribed her a series of
eight drug regimens, including three as part of clinical trials. Ms. MacKenzie,
71, of Massachusetts, switches from one medication to another when it becomes
clear that a treatment doesn’t work or has stopped working because her cancer
has figured out how to resist its effects. Some of these regimens have lasted
only a few months, while others have kept Ms. MacKenzie’s cancer under control
for longer. Of an oral type of chemotherapy she tried as her fifth line of
treatment, she said: “I was excited. I got 12 months out of that one.”
Like a hiker who comes upon a wide
creek and gingerly steps from one partially submerged stone to the next, Ms.
MacKenzie has moved from one regimen to another, each drug or drug combination
keeping her cancer in check long enough to get to the next one — until finally,
in 2020, she started taking a medicine that for more than two glorious years
has stopped her cancer from growing and given her a quality of life that’s very
close to normal.
“Of all the things I’ve been on,
it’s the easiest,” Ms. MacKenzie said. These days, she is more focused on her
grandchildren’s hockey and football games than the fact that she has a
supposedly fatal disease. In January, she and her husband celebrated their 50th
wedding anniversary.
If you know someone with late-stage
cancer, this kind of treatment regimen might be familiar to you. The approach
is increasingly becoming a standard of care for patients facing diagnoses that
were once death sentences.
Thanks to a combination of forces,
cancer drug development is now happening fast enough that for patients like Ms.
MacKenzie, it is outpacing the growth of cancer cells inside their bodies. For
these patients, cancer is more like a chronic disease than a one-time
catastrophic event.
Every time a new cancer treatment
approach emerges, oncologists and over-excited journalists have a habit of declaring
that a cure for cancer is imminent. What’s happening now is different. Rather
than a single breakthrough therapy or discovery, a variety of scientific
advances are exerting downward pressure on cancer mortality in new ways and at
the same time. As a result, the landscape for many cancer patients has changed
tremendously in just the past five years. The Cancer Moonshot, a
multi-billion-dollar initiative championed by President Biden, aims to cut the
cancer death rate by 50 percent in the next quarter century. The goal is lofty,
but recent progress against cancer means it’s now less far-fetched than it
might have once seemed.
“The pace of progress is most
certainly accelerating,” said Dr. Jedd Wolchok, an oncologist and director of
the Sandra and Edward Meyer Cancer Center at Weill Cornell Medicine. “There are
so many things converging.”
In some cases, patients like Ms.
MacKenzie with cancer that has spread inside their bodies — called metastatic
disease — are able to stay alive much longer than previously predicted. Some
are cured altogether by new drugs, a reversal of fortune that patients and
doctors dared not contemplate just a few years ago. In a growing number of
cases, patients with metastatic cancer are not cured but have access to so many
treatment options that they are able to leap from one to the next, changing
course whenever their cancer becomes resistant to a drug, always staying ahead
of their disease.
This is a new paradigm. Until
recently, the prevailing wisdom in oncology was that many early-stage cancer
patients could be cured, but metastatic disease was almost always incurable.
This thinking drove cancer research, treatment and care for decades.
Oncologists often threw the kitchen sink at early-stage cancer patients,
performing invasive surgeries and administering heavy doses of chemotherapy —
which can make patients sick to their stomachs, prone to infection and bald,
but can also have long-term side effects including infertility, heart damage,
numbness in hands and feet, brain fog and fatigue. The belief was that the only
chance to save the lives of such patients was to eliminate the possibility of
their cancer’s spreading. Since metastatic disease was usually considered
incurable, research focused on early-stage disease. For unfortunate patients
who developed advanced cancer, care typically consisted of additional rounds of
chemotherapy and palliative approaches. Now there is new hope for many of these
patients.
It would be foolish to argue that we
have the entire category of cancer in our cross hairs. Cures or long-term
survival for certain types of the disease — like pancreatic cancer and
glioblastoma, the form of brain cancer that killed Senator John McCain — are
still stubbornly out of reach. For people with these and some other forms of
cancer, the mortality rate has barely budged in the past 30 years. Researchers
are working to change this through more laboratory work and research. More than
800 pancreatic cancer clinical
trials are now recruiting patients across the country. And diseases
like breast cancer — for which there are many new treatments and more every
year — are still lethal for tens of thousands of people per year.
Outpacing cancer is currently within
reach only for certain cancers and patients, but the lessons learned on these
fronts are gradually being applied elsewhere. This is raising the possibility
that at some point in the not too distant future, diagnoses of any kind of
Stage IV cancer will dictate patients’ treatment, but not their fate. Or at
least that’s the promise for those with access to the most cutting-edge
science.
Right now, two relatively new classes
of cancer drugs are displacing traditional chemotherapy for many types of
cancer and giving metastatic patients, in particular, more time. Many of these
advances employ a person’s own immune system to eliminate cancer cells, rather
than using chemotherapy or radiation to do the extinguishing. These are modern
immunotherapy drugs and antibody-drug conjugates, or ADCs.
The idea that the immune system could be harnessed to fight
cancer is over a century old, but it took generations of painstaking laboratory
research and experimentation to do so effectively. While one major, Nobel
Prize-winning milestone came in the 1990s when scientists James Allison and
Tasuku Honjo became the first to uncover the proper mechanisms, it took almost
two decades before scientists and doctors translated the findings into drugs
that could be prescribed to patients.
The job of the human immune system
is to fight off harmful invaders, and it has checkpoints that stop it from
attacking healthy cells. Cancer cells can disguise themselves as healthy cells
and evade an attack by the immune system. “Checkpoint inhibitors,” a kind of
immunotherapy, help the immune system to recognize cancer cells for what they
are. The first blockbuster immunotherapy cancer drug, for melanoma, was
approved by the Food and Drug Administration in 2011 and was followed by more
new immunotherapy cancer drugs and combinations designed to treat many types of
cancer. The drugs have extended the life expectancy for some metastatic cancer
patients from months to years.
Former President Jimmy Carter, who
turned 98 in October, announced in 2015 that he had metastatic melanoma that
had spread to his brain. A decade ago, a patient like Mr. Carter would expect
to die in less than a year, but he was treated with an immunotherapy drug called
Keytruda, approved in 2014. It is one of the most successful immunotherapy
treatments on the market and is useful for more than a dozen types of cancer.
Mr. Carter entered hospice care earlier this year, eight years after his
diagnosis of Stage IV disease.
In June 2022, researchers at
Memorial Sloan Kettering Cancer Center and the department of pathology at Yale
University School of Medicine unveiled the results of a rectal cancer study that used immunotherapy and
put every participating patient into full remission, a staggering outcome.
While the study was small and the patients need to be followed over time, the
results — which experts have called “unheard-of”
— are already giving researchers and pharmaceutical companies new ideas about
how to leverage the approach for other patients.
ADCs, the other newer class of cancer drugs, work by
combining antibodies that can find cancer cells with very strong chemotherapy
drugs. An ADC is like a smart bomb that knows how to home in on a target
without causing very much collateral damage. Patients can often stay on ADCs
for a long time, even years or decades, unlike regular chemotherapy, which can
often only be given for a short period because it’s too harsh on the body.
At least nine ADCs have been
approved by the F.D.A. in the past five years, including one granted approval
early last year after researchers published a trial showing that the drug could
increase survival by nearly 50 percent for a large percentage of patients with
metastatic breast cancer. When the study’s principal investigator presented the
findings at a large cancer conference in June 2022, the doctors and scientists
in attendance gave her a standing ovation. The new breast cancer medicine is a
game-changer, and not a one-off. Rather, it’s a natural result of a new
scientific understanding that is altering the futures of patients with many
types of cancer.
The F.D.A. has long faced criticism
for its slow pace of reviewing drugs for approval, but it’s moving faster than
ever to get new drugs into the market. Between 2017 and 2021, it approved about
three times as many new cancer drugs and cancer drug uses as it did between
2007 and 2011.
Carol MacKenzie is currently taking
Trodelvy. In 2020 it was granted accelerated approval, which allows regulators
to provide patients access to medicines based on fairly scant clinical data; it
received regular approval a year later. She knows that Trodelvy may eventually
stop working for her and hopes that by then there will be a variety of other
drugs and drug combinations available or being tested in clinical trials that
will accept her for enrollment.
“Each time that you have something
new you wonder how many more things are there to try,” she said. It turns out
the path to a cure may not necessarily require one miraculous new drug, but
rather a constant flow of novel options to try. And in more and more cases, in
this new age of cancer drugs and science, these options abound. But not for
everyone.
The
overall cancer death rate in the United States decreased by a third between
1991 and 2019, largely because fewer people smoke and develop lung cancer. As
cancer screening, prevention and treatments for all types of cancer have
improved, this decrease has continued and even accelerated. The national cancer
mortality rate is falling by about 2 percent every year.
But despite these achievements, some
600,000 Americans still die every year from the disease, and glaring
disparities in outcomes for different groups are stifling faster progress. The
reality is that untold numbers of Americans are dying every year not because
they have untreatable cancer, but because they cannot get the treatments that
could save them. The Covid-19 pandemic helped expose the differences in health
outcomes by race and drew renewed attention to the need to close those gaps.
For some of the most common types of
cancer, the disparity in outcomes for whites and nonwhites is astonishing.
Black women are less likely to be diagnosed with breast cancer than white women
but are about 40 percent more likely to die
of the disease. Black men are more than twice as likely to die of prostate
cancer as their white peers. Some of these differences may relate to biology,
as some groups are at higher risks for certain cancers, but a large percentage
of cancer deaths among people of color are because of factors like lack of
access to high-quality care, higher rates of chronic illness due to a variety
of factors and structural racism built into the U.S. health care system.
It’s not just race. Wide disparities
also exist between high- and low-income patients, those with health insurance
and those without, people treated at academic medical centers where specialists
are immersed in the latest research and people cared for by overworked doctors
at community hospitals who may treat all types of cancer and are not as
immersed in the latest science for each type. Ms. MacKenzie is white and being
treated at Dana-Farber, one of the country’s best hospitals for breast cancer.”
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