ROCHESTER, MinnesotaFluorouracil (5-FU)-based chemotherapy after
surgery can be given safely to selected elderly patients with stage II/III
colon cancer, and these patients derive the same benefits from the treatment as
do their younger counterparts, according to results of a pooled analysis of
seven clinical trials.
Physicians will be seeing growing numbers of elderly patients with
colorectal cancer over the next 30 years. By that time, an estimated 20% of
Americans will be over age 65, commented lead investigator Daniel J. Sargent,
PhD, of the Mayo Clinic.
The Current Standard
Currently, treatment with 5-FU plus leucovorin for 6 to 8 months is standard
adjuvant treatment for patients with stage III colon cancer. "The benefits
of 5-FU-based therapy for stage II colon cancer are unclear, although many
trials permit the enrollment of patients after resection of either stage II or
stage III disease," Dr. Sargent said.
He pointed out, however, that elderly patients with stage II/III colon
cancer are less likely than younger patients to be offered or to receive
adjuvant chemo-therapy. Data from the National Cancer Institute’s
Surveillance Epidemiology, and End Results Program (SEER) show that only 48% of
patients aged 65 to 74 years received adjuvant chemotherapy for node-positive
colorectal cancer, and only 24% of those patients aged 80 to 84.
Reasons for withholding adjuvant chemotherapy from elderly patients may
include coexisting conditions, fear of toxicity, declining functional and
mental status, and lack of social support, Dr. Sargent said, but "most
people older than 75 are independent, and their life expectancy without cancer
is 10 to 12 years."
To investigate the effects of adjuvant chemotherapy in the elderly, the
researchers pooled data from seven randomized trials comparing 5-FU-based
regimens after surgery with no adjuvant chemotherapy for patients with stage
II/III colon cancer. Five studies used 5-FU plus leucovorin, and two tested
5-FU plus levamisole.