MILAN-An international study has identified diagnostic signs
to help spot breast-cancer patients at high risk for bone metastases who
might qualify for therapy with bisphosphonates.
A review
of records of 6,792 breast-cancer patients in seven clinical trials of
adjuvant therapy in nine nations, with a median follow-up of 10.7 years,
found that women with four or more positive nodes at diagnosis were at the
highest risk of developing bone metastases. The 1,220 patients who had a
local, regional, or soft- tissue first recurrence were also at the top of the
list.
Some 14.9% of the 2,163 women with four or more four
positive nodes developed bone metastases within two years of randomization,
compared with an overall rate of 8.2% at two years. Within 10 years, 40.8%
had developed bone metastases, compared with 27.3% at 10 years for the
entire cohort, Milan’s Dr. Marco Colleoni and colleagues in the
International (Ludwig) Breast Cancer Study Group reported in the Dec. 1
Journal of Clinical Oncology.
In women whose initial
recurrence was local, regional, or in soft tissue, who had a median
follow-up of 7.7 years after recurrence, bone metastases were found in 21.1%
within two years of the recurrence and in 36.7% after 10 years, according to
the group. The investigators came from five European nations, South Africa,
Australia, and New Zealand, and from the Dana-Farber Cancer Institute in
Boston.
Women younger than 35, patients with tumors larger
than 2 cm, and those with ER-positive tumors were also at an increased risk.
At 10 years, 36.3% of women younger than 35 had developed bone metastases,
vs. 27.6% of older women.
And 32.0% of women with tumors
larger than 2 cm developed bone metastases, vs. 21.2% of women with tumors
under 2 cm. So did 28.7% of women with ER-positive tumors, vs. 22.3% of
women with ER-negative tumors.
