A Cancer Genomics Study Of
Value: Done In Europe
By
Leonard Zwelling
Finally!
A group has figured out how to employ human cancer genomics
in a way that might benefit real patients. I know this seems like a harsh
statement, but most of the genomic studies I see are still just that—research
and not yet ready for prime time.
This
was a phase 3 clinical study that demonstrated that a subset of women with breast
cancer could benefit from genomic analysis of their cancers by NOT needing
adjuvant chemotherapy. This would minimize their risk of chemo side effects,
including the uncommon long-term sequella of acute leukemia.
The study was reported in the NY Times (above) but published in the New England Journal of Medicine (August 25, 2016) (http://www.nejm.org/doi/full/10.1056/NEJMoa1602253?query=featured_home). The study showed that a group of breast cancer
patients with high clinical predictors of recurrence, but low genetic patterns
for recurrence on the 70-gene MammaPrint panel but who received no adjuvant
chemo did almost as well of those in the clinical high risk group who received
the drugs. This suggests that the gene analysis panel may allow many women who
would otherwise get chemotherapy to forego the drugs and still do well. There
was still a detectable difference in recurrence rate in favor of the treated group,
but it was small.
This
is a real breakthrough. Now why wasn’t it done in America? (You didn’t really
think I had only good news to report, did you?)
What
is so impressive is that this was a true phase 3, prospective randomized
clinical trial. True, there were a number, albeit small, of patients who might
have benefitted from adjuvant chemo but did not receive it despite their
needing it by clinical standards alone. But this is really what genomics is
for, it seems to me. The authors say flat out that 46% of women at high risk
for recurrence from clinical metrics, might be able to forego adjuvant chemo if
this genomic analysis test is employed.
Now
if we could do a trial as rigorously in prostate cancer by assessing the best
way to treat primary disease–radiation, drugs or nothing and who gets
what. I believe such a trial is on-going and its results could be just as
important as the ones from this genomic study.
Addendum-Let’s
also give a hats off to Dr. Hagop Kantarjian for his article in the same issue
of the NEJM showing the antileukemic activity of inotuzumab ozogamicin, an
anti-CD22 antibody conjugated with a cytotoxic drug in patients with adult
acute lymphocytic leukemia. (http://www.nejm.org/doi/full/10.1056/NEJMoa1509277)
