Targeted cancer treatments far outperform traditional methods

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MIAMI, June 2, 2018 (BSS/AFP) – Cancer treatments that attack tumors based
on their individual genetic traits — not their location in the body — far
outperform traditional methods, extending survival for twice as many
patients, a study said Saturday.

The precision medicine field of targeted therapy involves testing tumors
for clues about their genetic mutations, and matching patients with new drugs
designed to block cancer’s growth on a molecular level.

Researchers in Texas began studying the impact of these therapies in 2007,
after seeing the success of Gleevec (imatinib) — a breakthrough drug
approved by US regulators in 2001 that showed huge success against chronic
myeloid leukemia.

The results of the first and largest precision medicine trial to look at
survival across a host of cancer types and many different targeted therapies
were released at the American Society of Clinical Oncology meeting in
Chicago, the world’s largest annual cancer meeting.

The study, called IMPACT, enrolled 3,743 patients at Texas MD Anderson
Cancer Center from 2007 to 2013.

All the patients had advanced cancers, or “end-stage disease,” involving
cancers of the gastrointestinal tract, breast, or lung. Melanoma and cancer
of the female reproductive tract were also included, along with more rare
types of cancer.

Those enrolled had typically tried at least four — and sometimes up to 16
— other treatments that failed to halt the growth of their cancer.

Patients who received molecular targeted therapies either got an
investigational drug then being tested in a clinical trial, or an FDA-
approved targeted therapy commercially approved for another indication.

After three years, 15 percent of people treated with targeted cancer
therapies were alive, compared to seven percent in the non-targeted group.

After 10 years, six percent of the targeted group was alive, compared to
just one percent in the other group.

– Still far from a cure –

On the whole, targeted therapies led to an average of four months of life
without the cancer advancing, known as progression-free survival, and nine
extra months of overall survival.

Those who were treated with traditional approaches lived just under three
months without cancer growing, and 7.3 months longer overall.

Researchers say the field has grown immensely since 2007, and that further
research will improve the range of therapies available to cancer patients.

“When IMPACT first opened, we tested for no more than one to two genes,”
said lead investigator Apostolia Tsimberidou, professor of investigational
cancer therapeutics at MD Anderson.

“Now patients are being tested for hundreds of actionable genes,
amplifications and mutations, as well as for immune markers,” she added.

“Ideally, in the future, patients’ tumor testing and cell-free DNA
analysis will become the standard of care at the time of diagnosis, in hopes
of making a difference for patients upfront, especially in those with hard-
to-treat cancers.”