NEW ORLEANSThe first results from a large international
study presented at the 40th Annual Meeting of the American Society of Clinical
Oncology (abstract 505) show that older node-negative breast cancer patients
can avoid axillary clearance and have survival outcomes similar to those of
women who undergo the invasive procedure. Stig Holmberg, MD, of Gothenberg,
Sweden, principal investigator for the International Breast Cancer Study Group
(IBCSG) Trial 10-93, said the study was performed to determine if sparing women
the trauma and side effects associated with axillary clearance would improve
their quality of life without compromising survival.
473 Patients Randomized
In the study, performed from 1993 to 2002, 473 women aged 60
and older (median age, 74), three fourths with clinically node-negative breast
cancer, were randomized to receive breast surgery with axillary clearance or
surgery without axillary clearance. Both groups received tamoxifen for 5 years.
The median follow-up was 6 years.
The groups were well matched and had the following
characteristics: 80% estrogen-receptor positive, 45% mastectomy, 33%
breast-conserving surgery with radiotherapy; and 23% breast-conserving surgery
without radiotherapy. Among the patients who had axillary clearance, 27% were
found to have node-positive disease.
The primary endpoint was quality of life by patient assessment,
using linear analogue self-assessment (LASA) scales, and by physician
assessment at sequential time points.
Secondary endpoints were rates of axillary recurrence,
disease-free and overall survival, and sites of first event. The study was not
designed to show equivalency between the arms in terms of disease-free and
overall survival. Patients were assessed at baseline, after surgery, and at
months 3, 4, 9, 12, 18, and 24.
By both patient-reported and physician-reported measures, side
effects were significantly increased and quality of life was poorer for
patients having axillary clearance, but this was mainly limited to the
postoperative period, Dr. Holmberg reported.
In the postoperative period, restricted arm movement was noted
in 38% of the axillary clearance patients, compared with 15% with surgery alone
(P = .00001). "However, after the postop period, the percentage in either group
was similar and approached preoperative values," he said. Physicians reported
arm pain in 23% of the axillary clearance group, compared with 7% with surgery
alone (P = .0001), but the differences were not significant at later time
points. In general, any side effects resolved and approached baseline values in
either group by 6 to 12 months.
Patient-reported quality-of-life measures included factors that
gauged how much they were bothered by problems with their arms, shoulders,
hands, and chest, and a global measure that asked how much effort it takes to
cope with their condition. Patients in the surgery/axillary clearance group
reported significantly more bother than those receiving surgery alone; however,
these measurements returned to baseline over time. There were no differences in
global measures at any points in times.
The axillary recurrence rates were similar between the groups:
1% with axillary clearance and 3% with surgery alone. "The incidence was low in
this clinically node-negative population getting adjuvant tamoxifen," Dr.
Disease-free survival and overall survival rates were similar
in both groups, although the study was not powered to show equivalency, Dr.
Holmberg pointed out (see Figure). At 6 years, disease-free survival was 67%
for surgery/axillary clearance vs 65% for surgery alone, and 6-year overall
survival was 75% vs 73%, respectively.
Sites of first recurrence were also similar between the arms,
he said. Altogether, 17% of patients had a breast-cancer-related occurrence and
21% had a non-breast-cancer second primary or death without recurrence.
"We concluded that avoiding axillary clearance in older,
clinically node-negative patients being treated with tamoxifen improved quality
of life, with no apparent compromise in disease-free survival, overall
survival, or axillary recurrence," Dr. Holmberg said.