A common blood protein test can predict which
breast cancer patients are at risk for recurrence after mastectomy.
The test may eventually help direct treatment decisions, speculate
researchers from the University of Texas Health Sciences Center at
Texas investigator Richard Zellars, MD, and colleagues found that
high levels of p53 protein accumulation were independently associated
with a significant increase in the local recurrence rate in 1,530
breast cancer patients treated with mastectomy. In fact, patients who
were were p53-positive were twice as likely to have a
local recurrence of cancer.
Relapse Rate Higher for Recipients of Mastectomy Plus Radiation
Risk of relapse in patients treated with mastectomy only was 16.5%
for p53-positive patients vs 9.1% for p53-negative patients. The
recurrence rate was even higher for women who had been treated with
mastectomy and radiation. In this subgroup, the risk of relapse for
p53-positive patients was 21.5% vs 9.3% for p53-negative patients.
Most breast cancer patients undergo testing for p53 to help determine
the likelihood of survival. However, this is the first study to
assess its value in predicting local recurrence in breast cancer.
A p53 test could become a valuable tool, like lymph-node
involvement, to help make decisions on further treatment,
commented Dr. Zellars. The advance is important, he continued,
because physicians know that 20% to 30% of lymph nodepositive
breast cancer patients will develop a locoregional recurrence after
being treated by mastectomy, but they dont know which patients
are at highest risk. One-half of patients who experience recurrence
will die of their disease.