SUNDAY, June 3 (HealthDay News) -- Treating advanced-stage colon
cancer patients with a combination of chemotherapy and the
tumor-targeting drug Avastin appears to prolong survival among
those who have already undergone the combination therapy at an
earlier stage of disease, new German research finds.
Avastin (bevacizumab) works by interfering with the growth of
blood vessels that tumors require to grow and spread.
In the United States, Avastin already is used in combination
with chemotherapy as the standard of care for both initial
treatment and second-line treatment, which is for patients who
require additional treatment for progressing disease.
The current study's specific finding that Avastin is beneficial
as a second go-round for patients with advanced disease could alter
the way patients in Europe are treated, given that typically the
combined therapy is used either as a first- or second-line
treatment, but not both.
"These findings confirm what many physicians and researchers
have long suspected: that extended bevacizumab treatment provides
meaningful benefits for patients with advanced colorectal cancer
without adding significant side effects," Dr. Dirk Arnold, director
of the Hubertus Wald Tumor Center at the University Cancer Center
of University Clinic Eppendorf in Hamburg, said in a news release
from the American Society of Clinical Oncology.
Arnold added that Avastin also could prove useful as a mainstay
drug for advanced patients who may have built up resistance to
their first-round chemotherapy.
"By simply switching chemotherapy drugs when the cancer
progresses and continuing with bevacizumab, we can make second-line
treatment even more powerful," he suggested.
Arnold and his colleagues are scheduled to present their
findings Sunday at the American Society of Clinical Oncology
meeting in Chicago.
In all, 820 patients with inoperable colon cancer that had
spread to areas outside the initial tumor region participated in
the study from 2006 to 2010. All had been treated with one
chemotherapy drug and Avastin as a first-line treatment. When it
came time for a second-line treatment, some patients received a
different chemo drug plus Avastin, while the others received chemo
plus a placebo.
The result: Those treated with the Avastin-chemo combination
experienced better median overall survival times (more than 11
months versus less than 10 months) and better progression-free
survival (almost 6 months versus about 4 months).
Dr. Frank Sinicrope, professor of medicine and oncology at the
Mayo Clinic in Rochester, Minn., characterized the study findings
as "especially important."
"This prospective study supports prior evidence for continuing
bevacizumab after progression of standard first-line chemotherapy
containing bevacizumab," he said.
And that, Sinicrope added, suggests that the German team's
observations have "practice-changing implications for advanced
[colon] cancer patients."
The drug, made by Roche, comes with a hefty price tag -- more
than $8,000 a month, according to published reports.
Arnold has acted as a consultant or adviser to Roche.
Last year, the U.S. Food and Drug Administration rescinded its
approval of Avastin to treat advanced breast cancer, saying the
risks outweigh the benefits for that use.
Data and results presented at medical meetings should be viewed
as preliminary until published in a peer-reviewed journal.
More information
The National Cancer Institute has more about
colon cancer.